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Bill discovers a number of Tecsun S-8800 Hidden Features

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Many thanks to SWLing Post contributor, Bill (WD9EQD), who writes:

I’ve owned a Tecsun S-8800 for about eight months and have come to enjoy it more all the time. It, along with my PL-880, have become my main work horses for shortwave listening.

The S-8800 is perfect on the desk connected to a wire antenna and the PL-880 is perfect for carrying around.

Since I knew of the hidden features of the PL-880, it got me thinking on whether the S-8800 had any hidden features.

A quick Google search turned up the following Web Page:

http://swli-05940-mi.blogspot.com/2017/03/tecsun-s-8800-hidden-features.html

I used Google Translate to get a rough translation and then spent some time testing the features out and also just pressing and holding buttons to see if anything else showed up.

Following is what I have come up with:

(Note: some of these are in the manual)

With the radio off

Toggle Longwave on/off: With the Radio OFF, Press & Hold 2

Toggle backlight permanently on/off: With the Radio OFF, Press & Hold 3  – Note that this means the light will be on even when radio is off. While the light does go out when radio is turned off, any operation of a control will turn the backlight on and it will then stay on. Too bad they just didn’t install a slide on/off switch. Plus I know of no way to turn the backlight on permanently without the remote.

Toggle Seconds display on/off: With the Radio OFF,  Press & Hold 8

Displays “0888”: Maybe this is version?: With the Radio OFF,  Press & Hold “Back”

Displays all segments of display: With the Radio OFF, Press & Hold “AM NORM” – Displays all segments of display. Press & Hold again to display “H802”

With the radio on in FM mode

Displays “75US”: With the radio ON, Press & Hold 5

Squelch Setting: With the radio ON, Press & Hold 9 – Range 0-5. Use Tuning Knob to set. Press 9 again to set.

With the radio on in SW/AM mode

Toggles Extended functions on/off: With the radio ON, Press & Hold 4

With extended functions on:

Press & Hold 6 – Toggles DNR (Dynamic Noise Reduction) on/off.

Press & Hold 9 – Squelch Setting. Use Tunng Know to Set. Press 9 again to set.

Squelch ranges:

MW: 0-40

MW with USB/LSB: 0-30

SW: 0-25

SW with USB/LSB: 0-30

So far that’s all I’ve been able to find. Has anyone else found any others?

Post readers: please comment if you’ve discovered other hidden features on the Tecsun S-8800! I’ll compile a complete list and post it separately.

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Tecsun S-8800 Hidden Feature: Frequency display calibration

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Many thanks to SWLing Post contributor, Dan Robinson, who shares the following procedure for calibrating the Tecsun S-8800. Dan received this procedure from Anna at Anon-Co:

Apparently there is a “hidden function” through which you can manually calibrate the SSB frequency display. Please follow the below calibration steps to see if it helps:

1) Turn on the device and set it to USB/LSB.

2) Now press & hold the “AM NORM.” button until you see the backlight blink twice (takes about 2 seconds).

3) Now press & hold the “MEMORY” button, until a certain value is shown on the display, for instance “6829”. This example value refers to a frequency like “xxx68.29 kHz”.

4) If you noticed a frequency deviation of 0.05 kHz up/down earlier, then you can use the main tuning knob to do the calibration. In the above-mentioned example, you would turn the main tuning knob to adjust the value to “6824” or “6834”.

Wow!  Thanks for sharing this Dan!  That’s two posts about S-8800 hidden features in one day. A record for sure!  Readers: please comment if you know of other hidden features.  I’m compiling a full list.

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Tecsun PL-660 Hidden Feature: FM Calibration

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Many thanks to SWLing Post contributor, Rick B, who writes:

I just thought I’d share with you a hidden function I discovered documented on the web for the Tecsun PL-660. It’s how to calibrate the FM band if you have a radio that is off frequency.

As my current PL-660 is accurate on FM, I haven’t had to try this myself. But perhaps it could save someone else from having to return/exchange a radio.

http://kaito.us/miscellaneous/qa/how-to-calibrate-the-pl660-on-the-fm-band.html

“Re-calibrating FM, radio needs to be on and set to FM band. Tune to the desired frequency/station you wish to listen to, press “SYNC” for about 3 seconds back light will flash. Tune up until the frequency/station sounds more clear press “1” to confirm re-calibration. If done correctly the correct frequency/station will be displayed on the display. Keep the battery in for all the time…”

Very cool!  Thank you for sharing the tip, Rick!

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Schematic for the PLL EDUTEC 4-Band Digital Radio Weltempfänger?

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Many thanks to SWLing Post contributor, Cezar Vener, who writes with the following inquiry:

I would like to ask you if you can help me with a schematic diagram for an EDUTEC 4-Band digital radio (PLL EDUTEC 4-Band Digital Radio Weltempfänger). It is not broken, but I would like to modify it. Of course, I could spend some time and manually extract the schematic, but I would lose too much time.

While I know that “EDUTEC” is a registred trade mark for technical (“non-food”) products that was sold by “Eduscho Handelsgesellschaft” in Bremen and also I found that it is now owned by Tchibo, well – I would like to kindly ask you for help in this matter? (course, if you can).

It is an old product, probably made in the 90’s and until now, I didn’t find anything on the net about it. I opened it and I found that its core is TA8132AN, and the FM section is made around TA7358AP. The audio stage is built with C1212C, and there is one more integrated circuit there, TA8148S (no datasheet on the net, but I found that is a DC-DC converter for electric tuning – built-in stabilized supply output for biasing VHF tuner variable capacitor / sine wave oscillation).

BTW, I found it also in SONY CFS-W504L 🙂

The PLL chip is soldered with the unmarked side, so I don’t know what type it is.

[See photo at top of post.]

Here is a photo of the rear back stand:

Unfortunately, there is no other model or name written on the radio.

I see there “CENTRON LABORATORIES LTD”, that points to the company with the same name from Gujarat, India. Very interesting :))

In the hope of an answer from you, please allow me to thank you and to congratulate you for the very nice site that you maintain there!

Many thanks, Cezar! It’s readers like you who make this site such a great one!

Post Readers: I hope someone may be able to help Cezar. This radio looks familiar–perhaps I’ve seen it badged with a different company name?  Please comment if you can help Cezar locate a schematic.

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How to fix the Grundig S350DL’s mechanical tuning drift problem

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The S350DL may look like a digital radio, but it’s actually analog inside and tuning is prone to drift.

Many thanks to SWLing Post contributor, Ed, who noted my comments about the Grundig S350DL’s tuning drift yesterday, and shared the following fix found on Jeff McMahon’s Herculodge blog.

Ed writes:

The Grundig S350DL’s mechanical tuning drift problem is reportedly easily correctable with a screwdriver:

(Source: The Herculodge)

[…]The drift on AM was terrible! After 10 minutes, it is jumping all over the place – if you touch the radio, the sound mutes and the display goes nuts. I pack it up to take it back but then I decide to google the problem and find this:

http://groups.yahoo.com/group/Grundig-S350/message/4644

I do exactly what he says – I pull off the cover after unscrewing all of the screws (including the 2 in the battery compartment).

Only the speaker is attached to the front. I remove the three screws from the display and then tighten the two screws on the tuning wheels. They were barely loose – almost not noticeable – so I was not too optimistic. I carefully got it all back together (the plastic pieces that hold the fabric handle on only go back on one certain way and were sort of a pain!). I cross my fingers, plug it in, and wow – a brand new radio. The tuning is perfect. Zero drift on FM and AM. AM sounds excellent.[…]

I have an earlier Grundig S350 that I bought at a hamfest years ago which had an easily-fixed power problem. For $20 it makes a nice bathroom radio and it sounds great, especially on FM.

BTW, I found schematics for it on radiomuseum.org, which is a great resource for radio schematics.

Thanks for the tip, Ed! I think I’ll crack open my S350DL later today and give this a try!

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Tecsun PL-680: Rolf touts enhanced performance using PL-660 mod

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Many thanks to SWLing Post contributor, Rolf Snijder, who writes:

I have made the same modification to the Tecsun PL-680, that was done [by many on the] PL-660 earlier.

The PL-680 is now a great radio; I think now one of the best! I do not own a PL-660, so I cannot compare.

Photo detail

Overview of modification.

For disable soft mute you can see the 2 joints and you must scratch a path on the print near the switch. (same on a PL-660)

Closeup of joint #1 (click to enlarge)

Closeup of joint #2 (click to enlarge)

With the tone switch [on the left side panel of radio] you can turn the muting on and off. On FM I need to set it on for better results, but on LW MW and SW always off!

Frequency adjust is with the pot: adj1391 in the right corner. (for the 1 kHz off freq)

Click to enlarge.

Hope I can help someone with this on your great site.

Greetings,

Rolf Snijder
Netherlands

Many thanks for sharing this PL-680 mod, Rolf! This seems like a simple enough project and one that can be undone if you aren’t pleased with the results.

Post readers: Please comment if you’ve made this modification to your PL-680 or PL-660 or if you have other successful modifications to share!

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Tecsun PL-300 series modification: disabling soft mute

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Many thanks to SWLing Post contributor, Troy Riedel, who shares the following tip. Troy writes:

While surfing the Net I found the following procedure that is said to “disable soft muting in Tecsun 300-series radios”.

I have a PL-390 and this has indeed seemed to work on it but I didn’t notice a difference with my PL-365.

Since I just found & tried this, I don’t know if this procedure must be repeated each time you use the radio? Maybe [Post readers] have heard of this before and/or have experience with it?

Here is the “reported” [supposed?] procedure that worked for the PL-390:

To disabling “Soft Mute” on Tecsun 300-series radios:

1. Select a shortwave frequency, preferably where there is no stations transmitting.
2. Tune down the frequency range with the dial, don’t tune up or it won’t work
3. Press the VF Scan button to let it automatically tune down
4. Tune down with the dial to stop the automatic scan. If the background noise is higher, then the “soft mute” / “dynamic squelch” has been disabled.

Thank you, Troy! I was unaware of this modification, but it seems easy enough to implement.

Post readers: Anyone have experience using this mod across the Tecsun 300-series receivers? Please comment!

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Rolf’s PL-680 modification allows external antenna on LW and MW

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The Tecsun PL-680

Many thanks to SWLing Post contributor, Rolf Snijder, who writes:

I did a modification today on the Tecsun PL-680 [which allows for an] external antenna on LW and MW.

The internal ferriet is also working, but on my active loop, MW and LW is now working !

So far away stations I can now receive on this portable radio.
It is only a560 pF capacitor added!

Click to enlarge.

Click to enlarge.

It works on LW and MW now with this mod.

FM is less now I think, maybe I will put it on a switch so I can turn it off.
And now also the ferrite is still working, so I hope to find a solution for that.

Many thanks for sharing your modification and photos, Rolf! Check out Rolf’s other PL-680 mod by clicking here.

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Tecsun PL-880 hidden feature/hack: 1 kHz bandwidth on shortwave

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[Note: This procedure was updated and simplified by Guillermo on 22 December 2017]

Many thanks to SWLing Post contributor, Guillermo, who writes:

I own the PL-880 and just discovered a new feature : a 1.0 kHz bandwidth mode on shortwave (SW only not in MW).

The procedure to get it is as follows:

  1. Turn on the radio and tune any frecuency on SW . There is no need to connect or disconnect an external antenna and turn on or off the radio during this procedure.
  2. Be sure that on SW the 4 button feature(press 4 for about 2 seconds) is ON and 9 button feature(press 9 for about 2 seconds) indicates a value of 13 or more and not less than 10.
  3. Then turn OFF 4 button feature and then ON again . Press BW button and see the 1.0khz new BW on the screen. Now you can use it permanently on SW and ALSO on MW , UNTIL you press BW button again .

Well, I hope you understand this description–if not please let me know, and tell me if it works on your unit, or it is just works on mine.

Thank you, Guillermo! I see where this is somewhat of a fragile adjustment in that a number of actions could change the bandwidth back to a previous setting, but nonetheless is quite a fascinating hack/hidden feature! Thank you and I’ll add this to our list of PL-880 hidden features.

Post readers: please comment if you can successfully enable the 1.0 kHz bandwidth on your unit.  Please comment with your radio’s manufacture or purchase date if possible.

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Rolf’s LED backlight mod for Sony ICF-SW35

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Many thanks to SWLing Post contributor, Rolf Snijder, who writes:

This is a simple LED backlight modification for the Sony ICF-SW35.

Simply add a 120K resistor and a bright LED:

Overview of resistor placement. (Click to enlarge)

Detail of Pin 10 (Click to enlarge)

Detail of resistor. (Click to enlarge)

Detail of Pin 10 (Click to enlarge)

Detail of LED placement–replacement of capacitor is not necessary. (Click to enlarge)

When you push the backlight switch, the light stays on.

When radio is turned off, the light goes off–then push light switch and backlight will stay on for 15 seconds or so.

Thanks for sharing this simple mod, Rolf!

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XHDATA D-808 modification to allow an external mediumwave antenna

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Many thanks to SWLing Post contributor, Rolf Snijder, who writes:

I have added an external antenna capability for mediumwave on the XHData D-808.

Simply add a 27 pF capacitor on the backside of the PCB on C10 to the the ferrite antenna.

The mod causes no loss on FM or shortwave!

I also replaced the Ferrite antenna with a bigger one so I now have more performance on MW!

Longwave is not good in my radio, even with an external antenna, it is not performing well.

Thanks once again, Rolf! I must assume that the Digitech AR-1780 could be modified in the same way as the radios appear to be near identical. Perhaps someone can verify this at some point!

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Pacific Island Results from Gary DeBock’s Hawaii Ultralight DXpedition

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Clearing the southern coastline of Maui en route to the Big Island. (Photo by Gary DeBock)

Many thanks to SWLing Post contributor and intrepid Ultralight DXer, Gary DeBock, who shares this DXpedition summary with recordings:


Kona, Hawaii DXpedition– Pacific Island Results

by Gary DeBock

From December 17-20 a Mini-DXpedition was conducted in Kona, Hawaii with a 5 inch (13cm) “Frequent Flyer” FSL antenna and a 7.5 inch (19cm) loopstick C.Crane Skywave Ultralight radio.

The FSL antenna was a new type designed to easily pass through TSA security checkpoints at airports, and provide inductive coupling gain roughly similar to that of a 4 foot air core box loop. South Pacific island reception was generally good from 0630-0800 UTC daily, but usually became problematic after that when powerful Asian stations tended to drown out the exotic Pacific island stations as sunset progressed over Japan, Korea and China. By 0900 daily only the most powerful Pacific island stations on 621, 846, 1098 and 1440 had much of a chance of surviving the Asian signal onslaught, and even some of those were drowned out. During a similar visit to Kona, Hawaii with identical gear in April (DXing at the same motel) the Pacific island stations were generally stronger, and had no co-channel competition from the Asians from 0800-1030 UTC. As such the South Pacific results during this trip were slightly down from April, although there were still plenty of strong signals to record.

The new 846-Kiribati on Christmas Island was a star performer as the strongest island DU station, with local-like signals shortly after the Hawaiian sunset each evening. Despite this it had an intermittent transmitter cutout issue, with the signal failing to transmit at odd intervals (including one stretch with six signal dropouts within one minute, as documented in an MP3 linked below). In addition 846-Christmas Island’s programming had a variable time delay with that of distant 1440-Kiribati in Tarawa, with both a 19-second and 35 second time delay noted. This may be related to the transmitter cutout issue, with the time delay changing after a major dropout. DXers looking for a parallel with 1440 should keep this programming quirk in mind. Although both 846 and 1440-Kiribati signed off at the usual 0936 UTC time on the first couple days of the trip, they had both switched to a 1009 UTC sign off on the last couple of days. Whether this is a permanent programming change is unknown, but the loud 1000 Hz audio tone is still being broadcast before power is cut, resulting in a very easy way to distinguish the stations at sign off time (even in heavy domestic QRM).

846 and 1440 weren’t the only exotic DU’s with transmitter issues. 621-Tuvalu came down with distorted audio on December 18th, a problem which got worse and worse on the remaining two days. By the last day it was sounding very garbled, making a bizarre combination with 621-Voice of Korea’s buzzing Japanese service transmitter. Whether 621-Tuvalu has repaired its garbled audio is also unknown.

540-2AP was somewhat weaker than it was in April, while 558-Radio Fiji One was MIA during the entire trip (probably because of Asian QRM). Efforts were made to track down 630-Cook Islands but only a weak UnID was recorded. 801-Guam was possibly received during a Pyongyang BS/ Jammer fade, but 990-Fiji Gold was given a golden knockout by 990-Honolulu. 1017-Tonga showed up for a couple of good recordings, but got slammed by Asian co-channels after 0830. Efforts to track down 1035-Solomons ran into heavy 1040-Honolulu splatter, while 1098-Marshalls became the only Pacific island station to have stronger signals than in April. Its overwhelming signals after 0700 daily were one of the bright spots in Pacific island reception. Finally the new 1611-DWNX in Mindanao, Philippines was received at a strong level at 0855 on December 19th, apparently with a major boost from sunset skip propagation.

540 2AP Apia, Samoa, 5 kW Christian worship music at a good level through the T-storms at 0751 on 12-17, but not nearly as strong as in April:

Click here to download audio.

621 R. Tuvalu Funafuti, Tuvalu, 5 kW This station had very strong signals until around 0800 on most evenings, when it usually began to be pestered by Asian QRM (China, N. Korea and NHK1). It also came down with a garbled audio issue on December 18th, which continued to get progressively worse until I left Hawaii. Sign off time is still around 1006, but by that time it ran the gauntlet of powerful Asian co-channels during the December propagation.
Local employment offers read by the usual lady announcer at an S9 level at 0750 on 12-18. This was the last undistorted audio signal recorded from the station during this trip; after this the audio went “south”:

Click here to download audio.

Guest speaker in Japanese-accented English, followed by local island-type music at 0835 on 12-18– the first sign of audio distortion:

Click here to download audio.

Full Radio Tuvalu sign off routine at 1003 on 12-18, but with China QRM initially. Tuvalu’s signal prevails during the national anthem, but the audio distortion is quite noticeable. The carrier apparently stays on for over a minute after the audio stops:

Click here to download audio.

630 UnID While trying for the Cook islands (Rarotonga) I came across this weak Christmas music with English speech at 0742 on 12-17, although this could just as easily be a west coast domestic station playing the “exotic” to fool a hopeful DXer. Walt says this station is a notorious underperformer:

Click here to download audio.

801 UnID (Guam?) Apparent Christian female vocal music received during Pyongyang BS/ Jammer fade at 0931 on 12-18, but no definite ID clues:

Click here to download audio.

846 R. Kiribati Christmas Island, 10 kW This newly rejuvenated station had awesome signals, and was overall the strongest Pacific island station received. Of all the Pacific island DU’s it faded in at the earliest time after sunset, and maintained its strength even during strong Asian propagation — as long as it managed to transmit without its signal dropping out. Unfortunately this seemed to be a pretty common occurrence while I was in Kona. Island-type music at typical S9 strength at 0735 on 12-18:

Click here to download audio.

This segment at 0620 UTC on December 17th features 6 signal dropouts within one minute:

Click here to download audio.

This segment at 0944 UTC on December 18th is even worse– 9 dropouts in 90 seconds:

Click here to download audio.

After a prolonged 846 transmitter dropout it seemed like the programming time delay between the distant 1440-Kiribati on Tarawa Island and the new 846-Kiribati on Christmas Island would change. On December 17th I recorded two different time delays– 19 seconds, as in the following recording (the MP3 starts out on 846 at 0635, switches to 1440 at the 1:02 point, then switches back to 846 at the 1:34 point, with a 19-second time delay evident between the 1440 and 846 programming (846 lags behind):

Click here to download audio.

Later on the same evening there was a 36 second time delay between 1440 and 846, with this MP3 starting off on 1440 at 0645, and switching to 846 at the 11 second point:

Click here to download audio.

1017 A3Z Nuku’alofa, Tonga, 10 kW Female native language speech at a very good level at 0858 on 12-19:

Click here to download audio.

Somewhat weaker through the T-storms on 12-17 at 0734:

Click here to download audio.

1098 R. Marshalls (V7AB) Majuro, Marshall Islands, 25 kW This station was very strong in Kona with its island music every night, and rarely had any Asian co-channels.
S9 Island music and native language speech (and possible ID) across the 0700 TOH on 12-17:

Click here to download audio.

Equally strong island music and native speech at 0813 on 12-18:

Click here to download audio.

1440 R. Kiribati Bairiki, Tarawa, 10 KW Somewhat weaker than its rejuvenated 846-Christmas Island parallel (which has variable programming delay times, as explained above), this home transmitter could hold down the frequency until around 0800 every night, after which it was usually hammered by JOWF in Sapporo. Despite this it often put up a good fight until its new sign off time of 1009, and it continues to use the loud 1000 Hz tone right before the power is cut (an awesome aid for DXers hoping to ID the station through heavy QRM).

Typical island language speech and strength level at 0830 on 12-18, just as it is starting to get jumbled by JOWF (a Japanese female “Sapporo desu” ID is at 25 seconds):

Click here to download audio.

Full sign off routine at 1005 on 12-19, including the National Anthem and the 1000 Hz tone before the power is cut. The tone gets through the JOWF QRM like a DXer’s dream:

Click here to download audio.

1611 DWNX Naga City, Mindanao, Philippines, 10 kW (Thanks to Hiroyuki Okamura, Satoshi Miyauchi and Mauno Ritola for ID help) Received at 0855 on 12-19, this station was a mystery until the Japanese friends matched the advertising format with that of a new, unlisted station which just came on the air in the Philippines. The propagation apparently got a major boost during sunset at the transmitter:

Click here to download audio.

73 and Good DX,
Gary DeBock (DXing at the Royal Kona Motel with a 7.5″ loopstick C.Crane Skywave Ultralight+
5 inch (127mm) “Frequent Flyer” FSL antenna.

Demo video of the “Frequent Flyer” FSL antenna:

Click here to view demo on YouTube.


Thank you for sharing your Hawaiian DXpedition with us, Gary! Your mediumwave DX catches with modest equipment reminds us all that when HF propagation is poor, there is still so much signal hunting below 2 MHz!

Interested in Ultralight DX? Check out archived posts in our Ultralight DX category.

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Guest Post: Supercharging the XHDATA D-808 with a 7.5″ loopstick

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Many thanks to SWLing Post contributor, Gary DeBock, for sharing the following guest post:


Supercharging the XHDATA D-808

Installation of High Performance AM and LW Loopsticks

By Gary DeBock, Puyallup, WA, USA, September 2018

Introduction

As a stock receiver the Chinese-made D-808 AM-LW-FM-SW-AIR portable is a very capable performer, with AM reception superior to that of any current Ultralight model, and impressive FM reception as well. The radio was certainly “inspired” (to use a generous term) by the C.Crane Skywave SSB model, which coincidentally was manufactured in the same part of China by C.Crane’s Redsun partner—with the first units going out the door a few months before the D-808 came into existence.

Because foreign intellectual property is routinely copied in China with no punishment from the government, XHDATA essentially had the chance to copy all the good points in the Skywave SSB design and improve upon its weak points as well. The only precaution that XHDATA took after this wholesale design appropriation was to forbid direct shipments of the D-808 from China to North America—presumably to avoid a copyright lawsuit by C.Crane. As such, the first D-808 models were sold to the rest of the world around January of 2018 at a price about half that of the Skywave SSB, while North American DXers were told that since the model couldn’t be shipped to the USA or Canada, they were out of luck.

Of course some D-808 models did make it into North America, where it was found to be a very capable portable with astonishing value for the price. Finally around March, an enterprising Chinese eBay seller came up with a plan to ship the model to North America through Israel, thereby skirting around XHDATA’s direct shipment prohibition. As of late August this eBay seller (harelan ecommerce) has already sold 62 of the D-808 models this way, even though he charges a premium for shipment to North America. Whether this single supply source will continue to serve North American customers is currently unknown, but out of the 7 models that I have purchased from him there hasn’t been a single D-808 model with any issues– despite the apparent lack of any manufacturer’s warranty offered on the radio.

Despite the D-808’s rather dubious design pedigree there is no doubt that the Chinese engineers (or reverse engineers?) did a superb job in creating an awesome radio for the money. Besides directly copying the Skywave’s SSB design and controls, XHDATA also made significant improvements, including a longer loopstick (providing clearly superior AM sensitivity), a much more powerful audio amplifier (correcting a serious shortcoming in the Skywave SSB) and a much lower price (about half that of the $169.99 Skywave SSB, for models shipped outside North America). Another great advantage for someone wishing to perform this loopstick upgrade are the perfectly located, highly accessible Litz wire connections on the RF circuit board—apparently used by the Chinese engineers to conveniently test out various loopsticks, and retained in the final product.  The radio’s high quality construction and survivability in adverse conditions were proven repeatedly over the summer here, with the model surviving accidental exposure to a 104 degree (43 degrees C) car trunk temperature, exposure to moderate rain, repeated travel bumps, and use as the main receiver during a 9-day DXpedition to a plunging ocean side cliff in Oregon state. The 3.7v lithium-ion rechargeable battery provides superior run time for extended DXing sessions, and is included in the D-808 shipping package, along with a USB cord to charge the battery, a plug-in wire antenna (for FM,SW and AIR), a vinyl carrying case, and a pretty basic English instruction manual.

One thing you will NOT find supplied with the D-808 is a warranty card– either in the shipping box, or online. This is pretty standard practice in China, incidentally, where concepts like refunds and warranties aren’t generally part of customers’ expectations. This doesn’t necessarily mean that XHDATA won’t repair obvious problems in a new D-808, but it does mean that they aren’t assuming the obligation to do so. I have heard from one North American purchaser who received a new D-808 with a defective speaker, and he is still waiting for the model to be repaired (after paying the shipping charge to send it back to China). Each individual purchaser must decide whether or not this lack of any warranty is a deal breaker. But if you are looking for a final reason to perform this loopstick transplant, why not consider the fact that you will not be violating any manufacturer’s warranty by doing so??

Realistic Expectations

Although this 7.5” loopstick upgrade will certainly make your D-808 far more sensitive than the stock model on Medium Wave or Longwave, it is not designed to compete with large (2’ sided or larger) inductively coupled box loops, or any of the new FSL antennas. The sensitivity upgrade will boost the D-808’s MW band weak-signal performance up to the level of classic portables like the ICF-2010 and RF-2200; however, and since the D-808’s DSP-enhanced selectivity will generally exceed that offered by these classic portables, the overall DXing capability in the AM mode could be considered slightly greater. The D-808 does have SSB capability, although it lacks the SSB tuning convenience offered by the ICF-2010 and RF-2200. It also lacks the ICF-2010’s superb Synch detector, a big advantage in weak signal DXing. But in portability, versatility and DXing value for the price, the “Supercharged” D-808 is a real winner.

Project Overview

This construction article will provide the builder with step-by-step instructions to upgrade the XHDATA D-808’s loopstick to a much more sensitive, externally-mounted 7.5” Medium Wave or Longwave loopstick replacement. Both the Medium Wave and Longwave 7.5” loopstick designs have been thoroughly tested and proven effective in actual DXing by hobbyists other than the author, and as long as the instructions are followed carefully, this relatively inexpensive modification will provide a major improvement in the D-808’s weak-signal reception capability.

This modification project involves close-order soldering on the D-808’s circuit board, and should only be attempted by builders with reasonably good eyesight, good hand coordination and soldering experience. The project also calls for the use of a precut plastic loopstick frame to attach the antenna to the top of the D-808’s top back cabinet surface, and the construction of this precut plastic frame requires either the use of a 12” (or larger) power miter saw, or some rather lengthy cutting with a hacksaw. Use of a power miter saw SHOULD NOT be attempted by those without serious power tool experience! The author assumes that only qualified power tool operators will attempt to use a 12” miter saw to cut these frames quickly, and that other builders who wish to construct them will use a hacksaw. As such, only basic cutting instructions are provided for the 12” power miter saw users, while detailed instructions are provided for the hacksaw users. To assist builders who are not qualified to use power tools, the author has prepared a LIMITED number of these precut plastic loopstick frames on a power miter saw, which will be offered at cost to these builders on a first come, first served basis.

A final warning is in order concerning the step of gluing the precut plastic loopstick frame to the D-808’s top back cabinet surface. Although this step is not dangerous, it is pretty tricky. Since the superglue “grips” very rapidly, you will only get one chance to ensure that the frame is straight, and centered on the D-808’s top cabinet surface. Do yourself a favor, and make multiple “dry runs” to practice this important step before applying the glue! Failure to take this step seriously will probably result in a crooked loopstick frame—which will hold the antenna just fine for DXing purposes, but which will be an eternal reminder to the DXer (and everyone else) of the hazards of haste.

Construction Parts Required

This 7.5” loopstick D-808 construction article will guide you through the assembly of either a 7.5” Medium Wave loopstick D-808 or a 7.5” Longwave loopstick D-808, so make sure that you order the parts necessary for construction of your chosen model. The picture above shows the parts that will be necessary for construction of either model, but the Litz wire and 7.5” ferrite rod components differ according to whether you are building the Medium Wave or Longwave model.

A)  XHDATA D-808 Receiver, currently available to North American purchasers (for $112.87 + $10. Click here to search eBay.

B)   Scotch brand “Extreme” strapping tape (any size roll)

C)   15 feet (4.6 meters) of 250/46 Litz wire (Medium Wave model). Click here to view on eBay.

OR 25 feet (7.7 meters) of 100/44 Litz wire (Longwave model). Click here to view on eBay.

D)  Two 120 lb. test plastic tie wraps (any length over 6”)

E)  Johnson Level & Tool Mfg. Co., Inc. 48” orange plastic carpenter’s level, part # 7748-O (provides enough plastic for two loopstick frames)

F)  Two 3/4” lengths of 1/2” I.D. clear vinyl hose

G)  Two 1” lengths of 5/8” I.D. rubber hose

H)  Roll of 2” Johnson & Johnson waterproof (medical) tape OR roll of 1” Rite-Aid waterproof tape

I)  Amidon 7.5” x .5” ferrite rod, part no.  R61-050-750 (MW model) OR part no. R33-050-750 (LW Model), available at http://www.amidoncorp.com/rods-and-tiles/

J)  6” of 1/16” shrink tubing

Miscellaneous:  One packet of Duro Super Glue (.07 ounce size), solder, 25w (low heat) soldering iron, hacksaw (or power miter saw), screwdriver set, sandpaper, needle nose pliers, diagonal cutters

D-808 Radio Preparation

Before starting the modification give the radio a thorough test on all bands, ensuring that all the stock model functions work properly, and that there are no issues with the display, speaker, headphone jack, battery or charging system. It’s also a good idea to run a daytime DX band scan on the AM or Longwave band (for whichever band you plan to construct an upgrade loopstick) and document the results—to use as a benchmark for the upgrade loopstick’s performance.

Step-By-Step Construction

Antenna Frame and 7.5 inch Loopstick Preparation

1)   Refer to the photo below. Using the “Supercharging the Tecsun PL-380” article (posted at  http://www.mediafire.com/file/du3sr5cd9thqvau/7.5inch-LS-PL380.doc/file or available directly from the author) carefully prepare the orange loopstick antenna frame according to construction steps 1-9, EXCEPT note that the lower (glue surface) edge of the antenna frame should be cut to a length of 5 3/4” (147mm), NOT 5” (127mm) as described in the PL-380 transplant article. Pay close attention to the safety precautions concerning power tool usage, and DO NOT attempt to use a power miter saw unless you have SERIOUS power tool experience!

2)   If you are constructing an AM (Medium Wave) loopstick, follow construction steps 10-16 in the PL-380 transplant article to construct the antenna. If you are constructing a Longwave loopstick, follow construction steps 10a-16a in the PL-380 transplant article to construct the antenna. If you are constructing both loopsticks, MAKE SURE that the ferrite rod and Litz wire are only used in the antennas for which they were designed. Mixing up these items is very easy, and such a mistake will make both loopsticks perform like clunkers.

3)   After construction of either the AM or Longwave loopstick, follow the instructions in steps 29 and 30 of the PL-380 transplant article to install a piece of 3 1/8” (79mm) shrink tubing, EXCEPT note that this length is slightly longer than the 3” (76mm) length called for in the PL-380 article.

4)   Refer to the photo below for the following three steps. [NOTE: Although this photo shows the AM (Medium Wave) loopstick, the procedures in this step are the same for the Longwave loopstick, although the position of the rubber hose lengths and clear vinyl inserts will be closer to the ends of the ferrite rod]. Carefully slide the length of 3 1/8” shrink tubing into the position shown, ensuring that there are no Litz wire kinks or bends inside the shrink tubing.

5)   Take the two 3/4” (19mm) clear vinyl inserts and slide them onto the ferrite rod ends, twisting them up against the border of the Scotch “Extreme” tape ends to lock the tape in place under the vinyl inserts. Ensure that the clear vinyl inserts do not touch any Litz wire leads or coil turns.

6)    Slide the 1” (25mm) lengths of rubber heater hose over the clear vinyl inserts until the appearance of the loopstick resembles the above photo. Ensure that the rubber hose sections also do not touch either the Litz wire leads or any coil turns. Finally, place the completed loopstick in a safe place until it is called for in Step  .

Radio Disassembly

7) Refer to the photo above for this step. Remove the battery from the radio, and using a Jeweler’s Phillips screwdriver of the correct size, remove the six identical screws in the positions shown (NOTE: These screws have a tendency to stick inside their slots, even when the slots are turned upside down. If you cannot remove all six screws it’s not a major problem, but at least ensure that the screws are completely loose in their slots, and that you don’t lose any of them during the remaining steps). Grasp the tuning knob, and pull it out horizontally in a completely straight manner to remove it from the radio. Ensure that the battery, tuning knob and all removed screws are placed in a safe place until the radio is reassembled.

8)   Carefully separate the front and back cabinet sections and place them down in the position shown in the photo below. Note that the front and back sections of the radio are connected by a ribbon wire plug-in system– ensure that this plug remains securely inside its slot at all times, and that no great stress is placed on the speaker wires.

9)   Refer to the close up photo below, and note the position of the two Litz wire soldering points on the circuit board (in the lower right corner of the photo). Using diagonal cutters, cut the two Litz wire leads at the position shown, UNLESS you wish to salvage this stock loopstick for other projects—in which case you should desolder the entire lengths of the Litz wire leads from the circuit board at the positions shown in the lower right corner (NOTE: The stock loopstick is of a fairly good design, and has an inductance that would be compatible with any DSP-chip Ultralight radio, providing an AM sensitivity boost in the process).

10)   Refer to the photo below. Using a flat Jeweler’s screwdriver with a 1/16” blade, carefully probe around all four sides of the stock loopstick to break all of the glue bonds. Work slowly and carefully around the perimeter of the ferrite rod, including the plastic covers on each end. Once most of the glue bonds have been broken the ferrite rod will begin to shift around as you break up the few remaining bonds, but until this point work slowly and patiently to break up the glue.

11)   Refer to the photo below. Using the flat Jeweler’s screwdriver, once all of the glue bonds have been broken and the ferrite rod is loose in its slot, lift the ferrite rod out of its slot on one side by prying up under the plastic cover on the end of the ferrite rod. Ensure that the Litz wire leads have either been cut or desoldered from the circuit board, then grasp the ferrite rod with your fingers and pull it completely out of the slot with a slight twisting motion.

 

12)   Remove the wrist strap, and refer to the photo below. Carefully pick up the two sides of the radio and place the back section in a vertical position as shown, with a heavy flat weight (barbell, or other heavy flat item) pressing up against the back cabinet section to keep it in a vertical position. Ensure that there is adequate, even lighting on the top cabinet section for the gluing process in the next step, and that the back cabinet surface will not shift around as you make the gluing “dry runs,” and perform the actual gluing of the loopstick frame to the top of the cabinet.

 

13) Take the previously prepared orange plastic loopstick frame, and ensure that its bottom glue surface is completely smooth and flat, with no uneven ridges on the edges of the glue surface (remove these with fine sandpaper, but ONLY on the ridges, and not on the rest of the flat glue surface). Using a damp paper towel, wipe the top cabinet glue surface and the loopstick frame glue surface to remove any dust or debris, then wipe them again with a dry, clean paper towel to ensure that they are both completely dry.

Take the loopstick frame and gently slide the frame over the top cabinet surface to ensure that both surfaces are smooth and flat. Refer to the photo at the top of the next page. Ensure that there is even, bright lighting on the top cabinet surface, and make several “dry runs” to place the loopstick frame in the exact center of the top cabinet surface (with 1/16”, or 1.5mm of space between the frame ends to the cabinet ends), and also 1/16” (1.5mm) of overhang above the front edge of the cabinet’s glue surface (NOTE: if you wish to simplify the process by lining up the front edge of the loopstick frame with the front edge of the cabinet’s glue surface it will still provide an acceptable result, but you will need to do some minor sanding of the whip antenna’s plastic slot post, as shown in the photo below. In either case, make repeated “dry runs” with the loopstick frame to practice placing it in the exact center of the top cabinet’s glue surface, since you will only get one chance to place it in the proper center position once the superglue is applied.

NOTE: The back of the loopstick frame has a beveled surface to permit full operation of the radio’s whip antenna after the frame is glued on the top of the cabinet surface. If the loopstick frame is glued with a 1/16” (1.5mm) overhang in front of the front edge of the cabinet surface then the whip antenna should have enough space for free operation. The alternative is to glue the two front edges lined up with each other to simplify the gluing process, in which case minor sanding may be required on the whip antenna slot post, as shown in the photo below.

14)   After making multiple “dry runs” and becoming familiar with accurate placement of the loopstick frame on top of the cabinet, refer to the photo at the top of the next page. After once again ensuring that the back cabinet section will not shift around during the gluing process, take the Duro superglue packet and apply a thin (1/8”, or 3mm) bead of glue along the center of the cabinet’s glue surface, extending it 5 1/4” (133mm)long, with equal spaces on both ends (as shown). While sighting the two sides place the loopstick frame carefully down in the correct center position as practiced previously, with the 1/16” overhang if desired. If satisfied with the position, press down on the frame to lock the two surfaces together securely. Usually the frame may be shifted around slightly within 1 or 2 seconds of placing it on the superglue, so use this brief time to promptly shift the frame to a straight position, if necessary. After a couple of seconds, though, you will need to be satisfied with whatever position the frame has ended up with (regardless, it will still hold the loopstick just fine, for DXing purposes).

15)   After the loopstick frame is securely placed and locked on top of the D-808’s cabinet surface, place downward pressure on the loopstick frame along its length in order to ensure a tight glue bond throughout the entire top cabinet surface. Continue this process for about one minute, and sight both ends of the loopstick frame to ensure that they are both completely flat against the D-808 cabinet.

16)   Inspect the front and back edges of the loopstick frame’s border with the D-808 cabinet for any glue seepage, and if any is found,  remove it promptly with the 1/16” flat Jeweler’s screwdriver blade. Glue should not be allowed to run past the frame edges. This completes the process of gluing the frame to the D-808 cabinet.

7.5” Loopstick Installation

17)   [NOTE:  The installation procedures of the Medium Wave (AM) and Longwave loopsticks are identical, except that the plastic tie wraps and rubber hose sections are closer to the ends of the ferrite rod in the Longwave version. The following photos are for the Medium Wave (AM) version,  but Longwave loopstick builders should follow the same steps, while referring to the Longwave model photo in the “Operation” section as a guide]

Refer to the photo below. Carefully take the previously prepared 7.5” loopstick and hold it in the position shown—in its slot, centered in the middle of the orange antenna frame, with the shrink tubing and Litz wire leads running down to the left. Take the two plastic tie wraps and install them in the position shown, centered over the rubber hose sections on the loopstick, while ensuring that no Litz wires or shrink tubing is bound under the plastic tie wraps.

18)   Refer to the photo below. Lay the two cabinet sections down flat as shown, ensuring that the Litz wire shrink tubing is in the exact position shown (if it isn’t, carefully slide it along both Litz wires until it is in this exact position). Carefully thread one Litz wire end through the empty wrist strap hole, then thread the other Litz wire end through the hole, as shown. Finally pull on the two Litz wires together from the right while guiding the end of the shrink tubing into the empty wrist strap hole, and pull a short section of the shrink tubing through the hole (as shown) to protect the Litz wire insulation from friction damage.

19) Refer to the photo below. Using the previous procedure to install shrink tubing (which is described in the PL-380 transplant article) install a 2.5” (63mm) length of shrink tubing over the two Litz wire ends, and shift the shrink tubing into the position shown in the photo. After this is done cut the two Litz wire leads to the lengths shown in the photo (NOTE: make sure that the ends of both Litz wires are cleanly cut, not frayed and at the minimum diameter before attempting to insert them into the shrink tubing. The process is much easier when the Litz wires pass smoothly through the shrink tubing).

20) Refer to the close up photo below. Using a low heat (25w) pencil-type soldering iron, remove the two stock Litz wire leads at the positions shown, taking care not to use excessive heat, or touch the adjacent components. Ensure that the new Litz wire leads are at the length shown when the leads are in a horizontal position throughout the cabinet, and cut them to this length if they are not.

21) NOTE: When tinning the 250/46 Litz wire it is essential that all of the individual Litz wire strands be completely soldered together for a length of at least 1/4” (6mm), with bright, shiny solder around the circumference of the Litz wire ends for this minimum (1/4”) length. The Litz wire must be heated with a clean, hot soldering iron around its circumference in order to melt the solder properly for this step]

Refer to the photo above. Pull the Litz wires up out of the previous position, and place a clean rag underneath them (on top of the circuit board) to completely protect the circuit board from any solder which might accidentally drop down during the tinning process. Using your hot 25w soldering iron melt a generous amount of solder on its tip, and work the soldering iron tip slowly and patiently around the circumference of each Litz wire end until there is a bright, shiny solder length of at least 1/4” (6mm) in a cylindrical pattern at the end of each Litz wire. When doing this, take great care not to allow any solder to drip down onto the circuit board below (i.e., make sure that your rag completely covers the circuit board). The final appearance of your Litz wire lead ends should resemble those in the photo.

22) When your Litz wire lead ends resemble the photo above, cut the soldered portion down to a length of 3/16” (5mm) and observe the appearance of the end of the Litz wire. It should have a bright, solid circular shape, with no gaps or individual Litz wires showing. If not, reheat the end of the Litz wire while adding some solder, and repeat this step.

23) NOTE: The Litz wire connection points on the circuit board are surrounded by other important components. It is important to avoid solder drips on these components, or solder bridges to their leads. Solder the Litz wire leads down at an angle to avoid these surrounding components, and use the minimum amount of heat and solder to ensure good electrical connections)

Refer to the close up photo above. Following the precautions described, solder the two Litz wire leads down onto the circuit board at an angle, as shown in the photo. After soldering, make a close visual inspection to ensure that there are no solder bridges across the Litz wire connections, or nearby components. The remaining length of the Litz wire leads should be routed in a horizontal manner to the wrist strap hole.

24) Carefully pick up the front and back cabinet sections, and hold the back cabinet section fairly close to the front section (as the radio would normally be oriented, when assembled). Refer to the photo below, and carefully insert the “Fine Tuning” control thumbwheel from the front cabinet section into its slot on the back cabinet section in a sideway movement. This will allow you to fully close the front and back cabinet sections in the next step.

25) Refer to the photo below. Pick up the two cabinet halves and carefully snap them together (this action should not require any great force). Place the radio face down in the position shown (with a soft surface underneath, for protection), and using the Jewelers Phillips screwdriver of the correct size, carefully screw in the six screws that were loosened previously, starting with the screw near the whip antenna post (you should pick up the radio temporarily and hold the two cabinet sections together tightly at this corner, as you do this).

After all six screws have been retightened take the Tuning control knob and press it back onto its shaft in a straight horizontal motion. Finally, reinstall the battery and battery compartment cover to finish up the reassembly.

TESTING AND OPERATION– MEDIUM WAVE MODEL

This 7.5” transplant loopstick is designed to provide a major boost in sensitivity from 530-1700 kHz, and if the antenna is working properly both the weak signal reception and the radio’s nulling capability should be greatly enhanced. It is normal for the antenna to receive more background noise on the low band frequencies, although the sensitivity boost should be substantial across the band.

The construction design of the orange antenna frame allows full usage of the whip antenna for checking SW parallels of MW-DX stations, although if you chose to glue the antenna frame flush with the front of the back cabinet surface to simplify the gluing process, you may need to sand the whip antenna slot post slightly to allow free movement of the whip antenna (see step #13).

In the photo above, some of the important controls for Medium DXing are highlighted. The AM Bandwidth control allows you to choose multiple DSP filtering selections to enhance selectivity as desired, with the narrowest filtering (1 kHz) providing both the sharpest selectivity and the best weak-signal sensitivity. However this 1 kHz setting also has the poorest audio fidelity, with the higher audio frequencies typically cut off by the DSP filtering. As such, for regular DXing far away from strong local pests, the other AM Bandwidth settings may be more suitable. The Direct Frequency Entry key allows you to manual enter in any MW frequency, to which the radio will shift once the numbers are pressed on the keypad. The Tuning knob has three different modes, which can be toggled by pressing the knob horizontally. The first mode is tuning in either 9 kHz or 10 kHz steps (depending on which of these step you have selected), while the second mode is tuning in 1 kHz steps. The third mode is to lock the frequency in place. Pressing the knob again will return the tuning to 9 or 10 kHz steps.

The XHDATA D-808 has multiple display functions, which can be toggled by the indicated key. The first option is the temperature in either Centigrade or Fahrenheit (depending on your pre-set preference), while the second option is the alarm time. The third option is the current time (which you need to set according whether you prefer UTC or local time), while the fourth option is the received signal strength in both dBu and dB.

The supplied 3.7v lithium ion battery has superior run time, and may be easily charged using the supplied USB cable to either a computer or AC outlet (with the appropriate adapter). As reported in various posts throughout this year, the D-808 model has rugged construction with an excellent record of survival under tough conditions, including hot summer days, moderate rain exposure and extended usage as the main receiver during a 9-day ocean cliff DXpedition in Oregon—performing flawlessly at all times.

Conclusion

It is the author’s sincere hope that this “Supercharged” D-808 model will bring you a lot of DXing fun during travel, as well as at other times. When conditions are good you should never underestimate this enhanced model’s potential of receiving awesome DX beyond your expectations—as an example, here is the stand-alone performance of a 7.5” loopstick D-808 in receiving 1017-A3Z in Nuku’alofa, Tonga (10 kW at 5,632 miles/ 9,063 km) on the ocean cliff near Manzanita, Oregon at 1301 UTC on August 8th of this year:

Not only Tonga is received, but even the Australian horse racing station 1017-2KY in Sydney (5 kW at 7,630 miles/ 12,280 km) is received as a weak co-channel in the middle of the recording. My hope is that you all will be so lucky with your new Supercharged D-808!

73 and Good DX,

Gary DeBock (in Puyallup, WA, USA)


Absolutely amazing!  Thank you for taking the time to put this procedure together and describing the process in such fine detail, Gary! Hats off to you! 

Click here to read all of Gary DeBock’s posts on the SWLing Post.

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An external battery pack for the Sony ICF-SW35?

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Many thanks to SWLing Post contributor, Adam, who writes:

Hi Thomas I enjoy reading your blog and often when I put a question in Google yours is the first on the list so I wonder if you’d mind if I ask you a question about the Sony SW35.

I’m interested to try powering it from a power bank but I have no idea what DC plug to buy for it as I bought it second-hand without an adaptor.

I thought about taking a couple of wires out of the battery compartment but it wouldn’t look as nice so any help you could give me would be much appreciated.

Great question, Adam!

You can certainly find a DC plug that will work with the ICF-SW35. I believe this same plug was used with a number of Sony Walkman type players back in the day. You might be able to find one at the local charity/thrift shop in their power cord jumble.

DC plug coaxial portI do know that the coaxial type plug needs to have positive tip polarity (click here to read about this in the owner’s manual) and the radio requires 4.5 VDC . The OEM power adapter (Model AC-E45HG) provided 700 mAh, but I don’t know what the ‘SW35 actually requires (other than something equal to or less than 700 mAh).

One option would be to find a 12VDC to 4.5 VDC converter like the Sony DCC-E345 and plug it into a 12VDC source (there are a number of high capacity 12V battery packs on the market).

Of course, you could also build your own external source by purchasing an appropriately sized external battery holder. I would use a D cell holder (I assume one to hold 3 cells at 1.5VDC x 3 = 4.5 VDC) which would provide much better capacity than a AA cell holder. (Something like this.)

I haven’t been able to determine the +/- voltage tolerance of the ICF-SW35, so I would keep the supply voltage figure at or below 4.5 volts.

One crucial number I’m missing is the coaxial plug size. I can’t seem to find a spec for OEM Sony AC-E45HG. I hope a reader might be able to help us here.

Post readers: Can anyone confirm the DC plug size for the Sony ICF-SW35?  If you have any other advice or tips for Adam, please comment!

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Tivdio V-115: Simple modification to abate internally-generated noise

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Many thanks to SWLing Post contributor, Marc Thomas, who shares a link to this site which describes modifications to eliminate the Tivdio V-115’s internal noise.

In a nutshell, the author made two small mods:

  • Decouple the power/battery with an electrolytic capacitor of around 10uF soldered to the battery connector inside the radio (see photo above)
  • The author also grounded the speaker, but didn’t test to see if this alone had any positive impact

I could not find contact details for the author of this mod, so I hope they don’t mind the fact I shared it here on the SWLing Post.

Note that the Tivdio V-115 is also known as the Audiomax SRW-710S and Kaimeda SRW-710S (and likely rebadged as a number of other models).

Click here to read reviews of this radio.

Retailers:

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Video: N1SPY brings a GE seven band radio back to life!

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Many thanks to SWLing Post contributor, Ivan Cholakov, who writes:

Thomas Cholakov (N1SPY) picked up an old General Electric radio from the 2019 Orlando Hamcation and brought it back to life. Unfortunately with all of the radio’s 7 bands, it did not have shortwave.

Click here to watch on YouTube.

Brilliant job resurrecting that GE portable, Tommy!!! Thank you for sharing.

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Imre’s HanRongDa HRD-737 modification increases sensitivity

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Many thanks to SWLing Post contributor, Imre Olajos, who writes:

Hi, HRD 737 lovers! I have a good news!

I  (became brave enough to) modify my HRD-737.

I tried reverse-engineering- but I gave up. No numbers on IC-s. I found specifications for the analog switches (one for each band ) and found information about the transistors around those analog switch IC-s. Nice, 1 GHz fT transistors, all surface mount, so I gave up that line.

I found an NPN SM transistor in a damaged TV remote. It is only a 300 MHz transistor but
I had no better than that, so I started to build a little antenna amplifier circuit, wide band and simple.

I lost a few SM capacitors during the soldering but I have plenty of those. So the 1/4 square inch circuit board was finished last week. I tested it with an external 3 volt battery and I found it good working. Today ( 07-27-2019 ) I opened up the HRD-737 and wired it into the radio.
The results are much better than I expected. The HDR-737 became a good shortwave radio!

When I touch the built in antenna by my finger, radio is sensing the touch and station comes in. This effect was not there before. Radio became more sensitive on CB band than my Realistic DX392.

I have a YouTube channel [in the following video/slideshow] and I will show you the little ugly but great working circuit in the radio:

Click here to view on YouTube.

Later on next week I will try to record some video of the shortwave reception and post up it on the same YouTube channel.

I am a shortwave lover since 50+ years and I will be very happy to share the good news with others. Now I can listen my Greek music on this little radio, on 9420 kHz. Yes, the radio became [more sensitive than I had hoped].

You can see my other shortwave radios on my YouTube channel too, Have fun and never give up the hope!

Many thanks, Imre, for sharing and documenting this modification. One of the lessons here, too, is that if you have an inexpensive radio like the HanRongDa HRD-737 and you feel tempted to try a modification, there’s little to lose. It’s not like modifying a $1000 transceiver–just dig into the little radio and give it a go. If you harm the radio, you’ve only invested $37 or so in the project. That’s a much better solution than letting it sit on a shelf collecting dust because it’s not sensitive enough! Well played, Imre!

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Jesse’s DX-390/ATS-818 modifications

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Many thanks to SWLing Post contributor, Jesse (W9JES) who writes: I’ve been busy enhancing my Radio Shack DX-390. I added an IF-Out jack for my SDR, changed out the light for a LED, added a latch circuit for the light switch, added static protection, and disabled auto-mute. My blog with full instructions is at www.w9jes.com […]

Video: Antonio’s Kenwood R-2000 Modifications

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Many thanks to SWLing Post contributor, Dan Robinson, who shares the following: Antonio Fernandez, who is in Spain, posted this on the Extreme page. Very interesting R-2000 mods: Major modifications are adjustable RF GAIN (using the former TONE control), BFO Pitch control (former AM Squelch, FM Squelch is retained) and DSP Audio filtering for SSB […]

You’ve Been Warned: Emilio just brought a Grundig Frankenradio to life–!

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Many thanks to SWLing Post contributor (and certified mad scientist), Emilio Ruiz, who writes: Recently I was given a broken Grundig G8 Traveler II.  This radio had an accident–the case, speaker, tuning knob, and volume controls were all broken or damaged. I discovered that the tuning and volume controls are not potentiometers, they are a […]
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