As I have written here before, I have a Radio Shack 200629 AM-FM-SW-LW portable radio with SSB/CW capability. This radio was first designed in December of 1999, and the design was edited and finalised in 2000. Some time after that, the Sangean company sold the radios as the ATS-505. The radio was produced for over 20 years.
The ATS-505 was intended to be the intermediate range of AM-FM-SW-LW radios, somewhere in between the big models -- ATS-909, and the 909X after that, and the smaller radios like the ATS-404.
Radio Shack, the former American electronics retailer, first issued their badged model of the ATS-505 as their "DX-402".
Also shown here is the MW/AM antenna (circled in red, bottom center), and the routes the MW signal takes, in pink. The MW/AM in the 200629 is configured like a boombox -- the MW radio signals go from the MW loopstick to the IF chip, from the chip to a mixer IF can & then through the ceramic filter back to the IF chip, where it's processed further before the signal is sent to the Audio amp chip -- and finally, to the headphones and speaker.
By the time the 2010's turned around, the DX-402 went by the wayside, and the "Radio Shack Synthesized World Receiver" was then introduced into Radio Shack's stores. Radio hobbyists instantly recognised it as a Sangean ATS-505, but unlike previous Radio Shack SW radios, this one didn't have a DX-xxx model number.
So it was known by various names. Most of us who have these little marvels call the radio the "200629", because that is the Radio Shack catalog number for the radio.
The 200629 has smoother, chuff-less tuning when you use the tuner knob (it sounds just like analog), and the audio chips are different from the AN7117's the original ATS-505 used. The new audio chips may have a little more power. Aside from that, and the black case (the Sangean ATS-505 is battleship grey), the operation of the 200629 is identical to the previous versions of the 505.
The back of the box my Radio Shack 200629 came in. The front side just has a cellophane window. The 200629 was the last Sangean radio that Radio Shack badged under its own label and sold in its stores. Within 2-3 years after introducing the radio, Radio Shack stores started closing all over the US, ending an era in electronics retail. I got my radio in the Summer of 2013. The store I bought it in closed within six months.
I got my 200629 in 2013. The Radio Shack store (in Wilderness Village, Maple Valley, WA) closed not too long afterwards. At the time, Radio Shack had been going through financial problems -- the electronics marketplace had changed, and brick and mortar electronics stores were going by the wayside. I actually have some fond memories over the purchase. In 2013 life was picking up a bit, and the MW band was loaded with long distance signals. Radio Disney was still on the airwaves, playing pop music, and SW had a lot more stations to hear.
And the pop music of the day was really, really good!
I still have the box the radio came in.
I have gotten a lot of use out of my 200629 over the years, with very few issues.
I previously wrote a fairly extensive article on the 200629 a few years back. You can find that article here.:
In that article I tell you how the radio works, how to get the most out of it, and especially how to DX the Medium Wave band with it, because it's really a sleeper DX radio. The bandwidth is about perfect, really, for an analog IF chipped portable. The tone control works really well, especially for DXing through headphones. The sound is also remarkable through headphones, and it is super easy to DX with this radio while using an external loop.
This is a section of the ATS-505 / 200629's schematic diagram, showing the stereo jack for the Shortwave External Antenna (left center). Below it you can see two diodes, reversed polarity, back to back, going between the 'hot' side of the antenna and the ground. What these diodes do is to conduct static electricity discharges to the ground, keeping them from frying the FET RF amp transistor, circled in orange at top center of the pic. Top left, the arrow shows the line coming from the whip antenna, showing that the connection from the whip is fairly direct.
The signal path from the whip antenna to the first RF amp is shown in pink, and the blue path is from the External SW Antenna jack. The stereo jack switches the whip off when the plug from the External Antenna is inserted into the jack. Inserting a mono plug seems to short circuit the connections somehow, maybe messing with the impedance the radios's RF amp is designed for -- but that is just a guess.
(Pics can be right-clicked and opened in new tab or window to see labels more clearly.)
There are only two weak spots with the 200629, and this may also apply to ATS-505's:
First, if you're listening to the SW ham bands using the BFO, it can overload on really strong signals. The CW or SSB will start to 'chirp'. The solution is to kick in the Attenuator "DX/Local" switch, putting it in local. Or you can just use the whip for reception when the signals are that strong (it's possible that you could wire a small resistor to an alligator clip, and clip it between your wire antenna and the whip antenna, too). It only does this form of overloading on the S5, CW and SSB signals, and there is little, if any overloading on AM broadcast SW or MW.
Secondly, if you use a mono plug on the end of your wire antenna, sometimes the SW External Antenna jack might cause some occasional feedback of some sort. It seems that the radio's EXT SW ANT jack is stereo, and it requires a stereo plug to work correctly. This issue, overall though, is not debilitating. If you don't have a stereo plug for your wire antenna, you can clip it to the whip and do OK. The circuitry is basically the same. But this issue -- using mono plugs in the stereo EXT SW ANT jack -- may be the same with some ATS-505's or 200629's, especially as the 2000 dated ATS-505 schematic I found online shows a stereo plug for the jack.
I wrote an article on the stereo plug / feedback issue, too. You can find it here.:
That said, since 2018 or so, if I listen to SW on my 200629, I just clip my indoor, 25-30 ft. wire to the whip. This is partly out of convenience, and partly because I lost my mono to stereo adaptor plug, and keep forgetting to get another one online.
Clipping the indoor wire antenna to the whip works perfectly for most listening, and from an internal circuitry standpoint, there really is little to no difference -- except I NEVER have gotten the feedback issue by clipping the wire antenna to the whip.
Now to the THIRD potential weakness -- and this is something that a lot of older Sangean SW portables seem to have: The whip antenna connection can get wonky. I.e., intermittent. And I'm not talking just the thing getting loose, and needing to be tightened. It acts up, cuts out, goes intermittent, even if you tighten the little set screw. This is after the radio is a few years old.
There's a reason for this. It's fairly well known among Sangean 'classic' SW portable enthusiasts.
Since 1989 Sangean has used a unique way of connecting a whip antenna (and sometimes the battery -- like with the ATS-803A) to their SW portable radios: there is this small, springy prong-like device, a little piece of metal that ends in what can only be called these tiny forks. This springy prong is attached to the whip, and then it touches a solder pad on the main printed circuit board. It's like a little spring-metal connector between whip and the antenna terminal on the PCB.
The springy prong-like thing gets weak over time -- or the prong wears down the solder pad that is on the main PCB. Oxidation on the tips of the prong also probably comes into play. Which means, the connection can go intermittent, because there is less solder for it to press against, and if there is any oxidation on the prong, that will interfere with the connection, too.
I had to hard wire my DX-440 / ATS-803A to overcome this, and I had to do the same thing with my DX-390 / ATS-818. I also hard wired my Realistic DX-370's whip to the PCB, and the DX-370 is a Sangean ATS-800A variant. A pic of this can be seen in a pic of my DX-370 I put in my DX-370 article.
My DX-370 article, with a pic of the wiring, is here.:
Now I've had to do the same operation to my 200629. A few months back, I was tuning the shortwaves and all the signals were weak. Then BOOM! They were instantly loud. Then after a while they cut back to weak again, and then BOOM! they were loud again. It was like someone was flipping a switch. I tested the DX/Local attenuator switch. That wasn't the problem.
The problem was elsewhere. I suspected the connection between the whip antenna and the radio. I tapped on the whip antenna, at the base -- on top of the swivel joint.
BOOM! The signals were back 100%.
That told me one thing: Houston, we've got a problem with the whip antenna connector!
I tightened the whip antenna. That seemed to help. Then it did it again, two days later.
I took the back off the radio and added solder to the antenna solder point on the PCB. That helped for maybe two more days, then it did it again.
It was time to hard wire it and get it over with -- a chore I put off for over a month. I really don't like taking apart my radios unless absolutely necessary. I just get the feeling that there is a limit to the number of times a radio can be dismantled and reassembled before those operations may lead to a failure somewhere in the radio. So I limit it to be on the safe side.
But in this case, I wanted my 200629 to work correctly on SW. So it was a necessary job to do -- time to solder a piece of hookup wire between the whip's base, and the Antenna solder terminal on the PCB.
(If you can't read the type in the pic itself, the pics can be right-clicked and viewed in a new tab or window).
Well, I finally fixed the connection, and this time there was a wrinkle in the process: you can't solder anything to the little prong, because it won't hold solder, and you can't solder a wire to the whip itself, because it won't hold solder either. There was no way I was going to hold the solder gun onto either the whip or the prong long enough to force them to take solder, because it might start melting the plastic case.
So here is what I finally did: I cut a little piece of hookup wire, and I stuck the bare tip of the hookup wire in between the whip antenna's butt end, and the prong, using the prong as a sort of washer. Then I tightened the little assembly together, basically squishing the bared tip of hookup wire between the whip antenna end and the prong's base.
The little screw that tightens the whip to the body of the radio is metal, as is the whip, so you can tighten it considerably without worrying about stripping it. Of course, I didn't overtighten it -- you're not holding elephants down, you're just securing the whip, hookup wire, and prong together securely. Those tiny threads aren't made for automobile cylinder heads, they're just designed to hold a whip antenna to the radio. So be careful when tightening.
Then I soldered the other end of the hookup wire to the antenna terminal / solder pad on the main PCB.
So far, it's working well that way.
In this pic you can see the DX-370's 120mm MW loopstick, at the top of the radio.
Next morning -- this morning, actually -- I test drove the 200629 on Shortwave, for two full hours or more. I had zero problems. The propagation was a problem -- even though it was 9 a.m., the 20 Meter, 17 Meter, 15 Meter, 12 Meter bands were all dead -- aside from some weak FT8 signals on a couple of the bands -- and the 11 Meter Outband was also dead. Most of the SWBC bands were spare, with the 31 Meter Band fading somewhat rapidly after 9:30 a.m. I did hear some CW on 20 Meters, and some week SSB on a couple channels in the SSB part of the band.
But what I heard was exactly the same on my other radios that I know for a fact work perfectly. So the 200629 was obviously working as it should. And I was able to catch a few SW broadcasts.
I heard China Radio International broadcasting to the Middle East from Kashgar, in Chinese, on 13710 kHz, so I know for a fact that the 200629 is doing its job OK.
And early on, before the 31 Meter Band faded into hiss and static, I heard Radio Free Asia in Korean on 9990 kHz, and Radio Free Asia in Korean with stronger signals on 9910 kHz, an UNIDentified station in non-Cuban Spanish on 9740 kHz; and in the 25 and 21 Meter Bands I heard what sounded like CNR-1 (maybe a jammer) on 11715, what sounded like Viet language on 11715 (Voice Of Vietnam, probably), CNR-1 jamming the Voice of Hope on 13670, and a weak WWCR-3 with a preacher on 13845.
So, the fix worked! My 200629 is back!
DON'T STRESS THE WHIP ON THESE RADIOS -- Just Not A Good Idea
A suggestion: don't swivel the whip on these radios too much, or if you swivel it, lube the swivel, and then whenever you move the whip, do it slowly.
This is because -- to be blunt -- there isn't a lot holding the whip, prong, etc. together. And that fastening screw, even though it's real metal, isn't very big, and the threads are very fine.
In fact, it's probably best not to rotate the whip at all if you're FM DXing. Even with the little fastening screw battened tight, there will be movement of the whip's base inside the radio. I saw this while testing it before putting the radio back together.
Rotate the radio instead. The connection just isn't built for being stressed. Even if you use a little lubricant on the swivel point and the rotation joint at the base of the whip, the whip has such a tight fit that rotating the whip, or swiveling it a lot -- it just is going to weaken the connection over time, and you'll have to tighten it over and over again -- and even though the little screw is made out of metal, I'm not certain just how much re-tightening that little screw is going to take before it starts to strip. As said before, the threads on it are very fine.
So don't overdo it if you use an ATS-505 or 200629.
I have no clue how many 200629's are out there being used. I know that my 200629 article gets about one hit a week or so, so there must be a few of you out there. There was a DX'er in my state who had a DX-402 (the earlier ATS-505 sold by Radio Shack), and his antenna broke. He was an FM DX'er, so possibly he had this particular issue.
Either way, if you have a 200629 or ATS-505, go easy on moving that whip antenna around, maybe lube the swivel so using the swivel doesn't stress the connection to the radio, and if you end up have to do some surgery, it can be done. It's not fun, but it's not really a difficult fix.
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Worse comes to worse, if by chance your ATS-505 or 200629 becomes unrepairable, you could take the whip off entirely, and solder a long bit of hookup wire to the terminal solder pad on the PCB, and then push the wire out through the hole, and clip another piece of stiffer wire to it if needed. But it doesn't have to come to that. I've had my 200629 for 11 years now, and it's doing fine. I am confident that if I reduce moving the whip around a lot, this fix should last. That little bit of hookup wire is squished in between the prong and the whip pretty tightly.
I've said several times that the 200629 is a great MW DX'er. This is despite the fact it's just a glorified boombox, circuitry wise. The IF chip, however, is a high gain one, and if you couple your 200629 with a good loop, and put on the headphones, you'll hear a LOT of DX with this radio.
I just heard WWL New Orleans 870 with it a couple nights back (they're almost a couple thousand miles away), using my homemade Crate loop antenna.
The radio gets the job done. Can't ask for much more than that. And the audio is so good, especially through headphones, that it's not a chore listening to either SW or long distance MW / AM. Good, smooth audio always makes distance listening a lot more fun.
With that, I will close this article. I hope it helped a few DXers out there with ATS-505's and 200629's. Some of this may apply to other, older "classic" era Sangeans, too (1990-2010 era SW portables).
See ya's.
C.C. April 5th, 2024.
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