Hallicrafters S-53A
 

I picked up a Hallicrafters S-53A table top shortwave radio at a garage sale this morning. Brought it home and the power cord was only about a foot long and obviously repaired. Went to plug it in and got a large spark between the two sides of the plug. Got it plugged in despite the spark (stupid I know) and it did power on. No sound, and only left it on for a minute. It looked like all but maybe 1 of the tubes was glowing. Anyway, the selector switch on the back was set to headphone rather than speaker. I went to plug it in again to see if this was causing the silence, but got another spark and decided not to plug it in again. (It was turned off by the way).

Anyway, any opinions on wheter or not a new power cord will solve this problem?

You'll want to replace the leaky caps (which is probably ALL of them) before using this. Owners manual is here: http://bama.edebris.com/manuals/hallicra/s53a/ - I see alignment listed, I assume there's a schematic as well.

Thanks for the link. Those are great manuals.

I have one of these receivers that I have restored and have been using for e few years now. They work great and are well worth the effort to bring back. You will want to replace ALL paper caps and electrolytics. This is a good transformer powered set so you don't want any parasitic loads. I have a schematic for this radio and if you need any information, please let me know.

I will start you off right by giving you the schematic.

On mine, I restrung the dials, replaced the front panel toggle switches and much more. It was well worth it. The S-53A is one well built radio.

S-53A Schematic
 

The schematic file is too large to upload. If you need it, let me know and I can e-mail it to you.

Compucat, thanks for the offer, but the link that Tom Bavis posted above has a nice scematic.

Regarding the capacitor replacement, they are listed in the manual as either

1) Ceramic
2) Tubular
3)Trimmer Assembly, 5 sections, antenna stage and Trimmer Assy. , 6 secs., oscillator stage
4)mica or silver mica
5) Folded Paper
6) Electrolytic (only one- the big can with 3-capacitors inside)

Of these, obviously you mentioned that you replaced the folded paper and electrolytic....but the rest are fine? I am not clear on what the manual means by "tubular"

Thanks!

The tubulars are most likely plastic encased paper caps. It has been a while since I worked on mine. They should be replaced. The ceramics and micas should not be bad. The trimmers should not need replacement unless they are physically damaged.

Also, you will want to check and/or replace any high value resistors in the power supply and audio output stages. Resistors rated at 1 Megohm or above tend to drift upward in value.

I took the radio out of its metal cabinet tonight, and you are right...the tubulars are paper...coated with wax or soft plastic. Access may be a little tight in some places, but no worse than any other table top radio, I suppose. Thanks again for the advise. I will update when I manage to find some time to replace these parts.

I would definitely replace the 3-section electrolytic cap as a matter of routine. As for the spark when you plug the receiver into AC power, that is a red flag if I ever saw one--there is definitely a short somewhere, and probably close to the input to the power transformer. I'd replace the cord first, before plugging the receiver in again. The S-53 dates back to at least the 1950s; yours may well have a dry-rotted cord that should have been replaced long ago--you will get a huge spark as you described if bare wires from the cord short against the chassis or each other, although I'm surprised the house fuse (on that circuit) didn't blow as soon as you saw the spark. I had a floor lamp in my apartment that shorted out from the same cause (bare wires shorting against each other) a few months ago; I saw a huge spark at the base of the lamp, after which the circuit breaker in the basement of the apartment building tripped.

When you had the receiver plugged in and switched on, did anything on the chassis (power transformer, filter caps, etc.) feel abnormally warm after the set had time to warm up? If the transformer felt extremely warm or so hot that it would burn your fingers, pull the plug immediately. The transformer is either shorted (a high-resistance short will not blow a line fuse, but a low-resistance short will) or else something in the radio is drawing much more current than it should. If the filter caps are warm or hot, yank the plug as well, as the capacitor(s) is/are dead shorted--these capacitors are in a position to blow the house fuses (because they are connected effectively directly across the AC line) if they short.

If the short in your S-53 were anywhere after the AC input, it should have blown the receiver's own fuse if it has one, which it should--Hallicrafters communications receivers were all equipped with a line fuse that will blow in case of any major low-resistance short, such as a shorted rectifier tube or a short in the power transformer, to name just two such shorts that should indeed blow that fuse if it's the correct size.

As to all but one of the tubes glowing when you had the receiver plugged in, that's a dead giveaway that the unlit tube is dead as a doornail and must be replaced. In fact, the unlit tube may very well be the reason why the radio won't work (if the dead tube is in an audio stage, for instance, you won't hear a thing from the speaker). However, until you at least replace the cord, don't plug the receiver into an outlet. As it is now, the radio has a dangerous short that must be found and corrected (not to mention being a shock hazard) before the set can be used.

Kind regards,

Well, here's what my Fred Osterman "Shortwave Receivers:Past & Present"-the "Bible" of this stuff- has to say...S-53-1948-1950, scarce, 8 tubes, was about $80 when new. The S-53A was made from 1951-57, is fairly common, & was about $90 when new. Doesn't look like there's any real difference...

The differences between the S-53 and the "A" version are that the "A" has civil defense markings on the dial and uses miniature IF cans. The S-53 has no CD marks and uses full size IF cans. Other than that, they are the same radio.

Jeffhs, after taking the unit apart the cord is even more pitiful than is appears and could very easily be shorting on te cabinet. There actually is no fuse in this radio that I could find. The power cord hooks directly to the rectifier tube and then off to the power supply.

If I wanted to add a fuse for safetly, where would it go?

When I did have it turned on, nothing felt abnormally warm, but I only had it on for 1-2 minutes. Is there a way to determine if the power tranformer is good before I replace all of the capacitors?

If I am able to get this radio working, I do want it to operate safely. Is it advisable to send this off to someone who knows what they are doing or is it all pretty straight forward (I don't want to burn my house down or "electrify" my friends and family)

1951-57. I guess this radio is from late in the 53A production run because it is stamped Mark II on the chasis.

I don't think you should get all that excited over that S53-a. I used one 40 years ago as a Ham Radio Novice. It worked but just barely. It was just another in a long line of Hallicrafters cheap radios that they were producing. If you look at the dial, there's only about 1/2 inch of dial space to cover the 40 meter band. It did work but there are many more receivers out there that have more value. Anything with "half moon" shaped dials will be more valuable.

The only thing about this radio that isn't that great is the BFO. It is practically useless for receiving voice SSB transmissions. It was obviously designed for use with CW code transmissions. As a shortwave program listening receiver, it is excellent and I've had good results with mine using a 12 foot piece of wire run along the floor.

Also, there is no line fuse in this radio. When I got mine, a replacement line cord had been poorly spliced in by hand (no solder) to the tube socket and the wire covered with electrical tape. I completely diassembled that radio, did a full cleaning and restoration and corrected a few hack repairs in the process. Now it is on its second fifty years of reliable service.

Well, I replaced the power cord yesterday and now the radio is working pretty well. Last night I was able to pick up AM stations from Atlanta, Houston, Chicago, and Kansas City. Shortwave from Cuba, Venezuela, Canada, Isreal, China...lots of others....plus that crazy Spanish counting lady.

Will need to recap when I have time. The unit runs somewhat hot so hopefully that (and replacing the high value resisitors) will take care of it (Although I don't know how hot it is supposed to get)

The coarse bandwith adjuster is fairly...well...coarse. But there is also a fine tuning knob that makes it easy enough to tune in stations. It meets my needs as someone who isn't a dedicated shortwave listener, but does enjoy playing around with it from time to time and getting different perspectves on news and world music.

Jeff,

Excellent find there mate. I too am the proud owner of a Hallicrafter S95 thanks to jaymanaa and the last AK Crap Swap. Mine is in beautiful shape outside.

I just found the manual on-line at the link above too.

Now I need to tinker with it and see if I can get it working. I've been so busy I've neglected it.

JD

Hallicrafters S-53/53A BFO
 

If the BFO works for CW it should work for SSB. I've had receivers in my 34 years in ham radio (and several years prior to that as a shortwave listener) that have had so-so BFOs, such as a 1936 Hallicrafters S19R "Sky Buddy" (which was little more than a broadcast receiver with SW coverage thrown in almost as an afterthought) et al., but they still did at least a passable job of receiving both sideband and CW. (When tuning in a SSB transmission on one of these radios, or any SW receiver with a BFO for that matter, one must tune in the signal exactly so as to beat against the BFO signal; this is a skill that is learned and perfected only by practice and experience.)

I think the problem lies more in the S53's tuning arrangement than anything else. As was pointed out in another post, the tuning is extremely critical on this set; mention was made that the amateur portion of the 40-meter tuning range is only about 0.5 inches wide on the tuning dial (I looked at a picture of the S53 on another site and saw just what the person was talking about--the radio doesn't have a decent bandspread control either; that is to say there is a bandspread adjustment, but it is nowhere near as good as a more expensive receiver would have). These receivers were made for casual shortwave listening and Novice amateur use, not serious communications purposes. There were countless other very low-end SW sets made in the '50s and '60s aimed at beginners in radio, such as Allied/Knight-Kit's "Star Roamer" four-band receiver, Heathkit's GR-64 and GR-54, and even Knight's "Ocean Hopper" receiver. The S19R Hallicrafters receiver I used before I got my Novice ham license was terrible. I could get decent reception on the BC (broadcast) band up to about 10 MHz or so, using an outdoor wire antenna, but I don't recall ever hearing anything much on band 4 which tuned up to about, IIRC, 35-40 MHz (the low end of this band was somewhere around 20 MHz). The best amateur-band receiver I ever used was a Hallicrafters SX101A Mark III, which was the receiver in my Novice amateur radio station in the early 1970s; it beats everything, including my present HF rig and almost all that followed it. This receiver could hear signals most other general-coverage sets wouldn't touch; its tuning dial, which was calibrated, of course, for ham bands only, was perhaps a foot wide on each of the six bands the receiver covered, so there was no need for a bandspread control.

Ham band only receivers are the way to go if you are serious about amateur radio; sets such as the S53 and others by Hallicrafters, etc. are good to start out with or to use if you aren't sure how much you'll like being a ham, or even if you'll be in the hobby for long, but if you plan to branch out into areas of the hobby such as message traffic handling with the ARRL's National Traffic System or contesting, etc. receiver and antenna upgrades are a must if you want the maximum enjoyment of these facets of ham radio.

It makes no sense to spend hundreds of dollars on equipment for an amateur station if you are only going to use it a year or two, let your license expire, then put the gear away in a closet or basement and forget about it. I was a member of the ham radio club in high school in suburban Cleveland, circa early 1970s; when I first joined, in my sophomore year, we had five licensed amateurs including myself, all Novice class (except one upperclassman who had a General license at the time and went on to get his Extra class soon thereafter). Two years later, in our senior year, that number had dropped to one. The others had let their Novice tickets expire, but by the time we graduated I had my Technician license; I later (as in ten years hence) took and passed my General class test and earned that grade of license, which is what I hold now.

I apologize for going off-topic as I am sure I just did, but when I get to talking or writing about amateur radio I cannot seem to stop. This has been one of my favorite hobbies for almost 35 years; I am not about to give it up (just renewed my license for another decade), even though my move from a three-bedroom house to an apartment almost seven years ago has forced me to use indoor antennas, which don't seem to work very well (at least on HF--high frequency, 3-30 MHz) with my equipment which now consists solely of an Icom IC725 nine-band 100-watt transceiver I won as the grand prize in a hamfest ticket drawing 15 years ago. Also, for two meters, I have an Icom IC-T22A handheld transceiver. I'm a member of the Lake County, Ohio, Amateur Radio Association and frequently participate in the club's Thursday-night 2-meter ragchew net. Those of you in the Cleveland area, especially Lake or eastern Cuyahoga County, with at least a Technician license are welcome to join in. You do not have to be a LCARA member, although the club is always looking for new members regardless of license class or even if you are not yet licensed. (LCARA also has volunteer-examiner testing sessions for all classes of license at least once a year.) The net is on the LCARA 2-meter repeater, 147.81-147.21 (tx/rx [transmit and receive] repectively, +600 tx offset).


73 (best of regards in ham talk),

Hi, I just wanted to thank you guys (and the rest of AUDIOKARMA'S contributors) for the vast amount of knowledge one can find at AUDIOKARMA! Because of this thread in particular, I now have a schematic AND advice for my S-53a. I've been carrying this around with me since I left my parents in 1976. It still sports the broken tuning knob that was caused by me yanking on the power cord some where around 1960, when I was 2. It still works great, but the more I read here, the more I realise that it's time to put togather a work area and go through all the old stuff I've ignored for the past 3 decades! Thanks agian!