First Zenith Royal "500" Transistor Radio Repair 1955

[SpeakerFreak95]

your royal had the same squeal problem as my royal 500H before its caps were replaced.

[Teflon65]

This is interesting. I have an old transistor radio, made to look like a Sinclair gas pump. It doesn't work at all, and I don't have the equipment to fix it, or a real clue as to how to do so. It was made in Hong Kong, but I don't know by what company.

[meyiyiyi55]

thank you for this inside look.very helpful.

[AllAmericanFiveRadio]

Thanks meyiyiyi55

Hope it helps.

[OlegKostoglatov]

Those early transistor sets are getting like tube radios now, if you want one to work properly change the condensers first, some won't work at all unless you do.

[AllAmericanFiveRadio]

Thanks OlegKostoglatov

Yep, exactly

[n4lq]

There is no such thing as a "biasing capacitor" or a capacitor that is biasing. Leaking capacitors can certainly change the bias however.Leaving a bad capacitor in circuit is a very bad example.

[AllAmericanFiveRadio]

Go back to the books and study some more. True it is a bad practice to leave old caps in. I left them in so that I would not lose them. It is not a customers radio.

[timothyone1]

When bridging capacitors do you use the same spec cap or try to guess at some value based on the 2 being in parallel? Thanks, and I very much enjoy your videos!

[AllAmericanFiveRadio]

Cut one side of the old and get as close to the original value as possible. Thanks.

[breen234]

i'm rather new to electronics, and i could use a little advice with a radio i'm working on. it's a 1959 RCA victor transistor radio. the problem is that the only noise i can make it to make is when i turn the volume knob, which creates a crackling noise. other than that, the radio is completely dead- not even any static. any advice would be great. thanks!

[AllAmericanFiveRadio]

Most of the time if all the electrolytic capacitors are replaced with new ones the radio will start playing. That is usually is the first step.

[breen234]

thanks for the advice! i'm trying to find the parts right now.

you have great videos, btw.

[AllAmericanFiveRadio]

THANKS

[trisoctehedron]

You already taught me something, even though I'm a ham and know some electronics: I would have thought the electrolytic capacitors' standard method of failure would have been to develop high leakage, so bridging them with good caps wouldn't have caused any change. Can you enlighten me on this?

[AllAmericanFiveRadio]

Electrolytic caps can open, short or turn into a resistor. For a customers radio I would remove the old caps completely and for a tube radios I always remove them completely because the voltage is much higher. Thats removing them electrically, I try not to leave holes in the chassis.

[trisoctehedron]

Thanks!

[watcher818]

Musicman quote " I'm curious to know why the older style radios had square magnets on the speakers instead of the modern round magnets"

Rick will verify this, but the square part is not the magnet. That is part of the speaker frame. Tha actual magnet is centered inside that square frame, if you look closely, and can see it is cylindrical.

Great video Rick. I just picked up a 500H last night in perfect shape for $5. Low audio though and needs a recap I suspect.

Take care, G.Rabbitt.

[AllAmericanFiveRadio]

Hey the square part is just the frame. Glad to hear you found a 500H in perfect shape. All of them are getting harder find. Thanks. Rick

[panheadrob]

hello great vid just picked up a zenith r 2000 in really nice shape and has exactly the same problem thanks for the vid geuss il start at the caps take care

[AllAmericanFiveRadio]

Hope you get it fixed!

[jenko701]

I live in the Triangle to,I thaught I was the only one that loved these old transistor radios .I have baught many radios at the state fair grounds to.Thanks

[AllAmericanFiveRadio]

Well, I have to get there early tomorrow. LOL. Thanks!

[musicman0150]

When you do the video on speaker technology describing the purpose for field coil speakers and permanent magnet speakers with square and round design magnets, also include any information about the transformers that are used on the speakers, such as 70v line hookups; and whether they are similar to field coil speakers or totally different so that I won't damage any euqipment when making subistutes. I'll even post a video showing what I use for better understanding.

Gary

[musicman0150]

I have watched this video many times and have enjoyed every moment of it. What I'm curious to know is why the older style radios had square magnets on the speakers instead of the modern round magnets? If possible, can you do a video about the speaker technology from the old to the new, explaining the structure and purpose of the design, I've always been fansinated by the old speaker designs and how they've changed slightly over the years.

Gary

[AllAmericanFiveRadio]

Good idea. I have started a list and called the file YouTubeThingsToDo. This is the first idea in the file. Thanks!

[1bobair]

I enjoyed this video and I collect these radios and have all of the Royal 500s made between 1955 and 1961(Royal 500H).I as a matter of coarse always replace those caps even if they are good as they can fail at anytime and any across the battery supply can short and cause a fire.The tuning cap is dated coded as are the transistors,so which ever is most recent,add a month and that will be ~ how old the set is.Thanks for posting.

[AllAmericanFiveRadio]

Thanks. How many have you collected so far? I am very happy to two hand wired Royal 500s. I collect a little of everything I have more 1920s radios than anything else. I find it all very interesting and fun. Here's all the number I can find now, there may be more. On the battery paper 7XT40, 102-1809, on the tuning cap MC273 and 620 013 and 22-2897, Serial number 46269. The other one, on the battery paper 7XT40, 102-2051, on the tuning cap MC273 and 622 013 and 22-2897, Serial number 45453.

[1bobair]

I have not added much in recent years but I have at least 300 Royal 500's to date but none of those unattractive sets after 61'.

[AllAmericanFiveRadio]

You should have a large number of pristine sets. I have not seen much around Ham Fest or Flea Markets in years, everything is going to ebay of course.

[glianx]

informative... thanks for posting this...

[Martyd64]

What is the brand/model number of that signal tracer?

[AllAmericanFiveRadio]

It is an asi (advance schools, inc.) TRANSISTORIZED SIGNAL-TRACER, no model number. I did do a video on just this tracer "Signal Tracer Transistorized"

[gli7utubeo]

I've got a couple of Zenith Royal 66s.

[AllAmericanFiveRadio]

That would make an interesting video.

[jim874]

Good work.

Noticed on this and the TransOceanic video that you have some serious line noise.

I just finished a Hammarlund HQ-170. Sometimes you miss the very obvious... in my case a broken lead off an IF can.

Also, I repaired a black one of the 500's as a teen... my great aunt had managed somehow to break the antenna lead...

Great videos.. Keep them coming.

73

Jim

WA8SDF

[AllAmericanFiveRadio]

I live a little over a block from the main power feed for the whole area, and it is nosy. But if I lose power it's back on very quickly. I can hardly wait for the broadband over power lines. Nice BoatAnchor, nice BIG and heavy chassis, lots of IF's and about 17 tubes I think. Thanks!

[Organgrinder010]

Fantastic work! I have a few old transistor sets around, but never thought much of them until now. This is inspiring.

[AllAmericanFiveRadio]

Thanks, I appreciate that! After writing two books on radio repair I had to take a break for awhile. But now I'm ready to get with it again. I invite you and you-all to download my new book. The video is in my playlist.

[douro20]

I did an old RCA clamshell once; replaced all the electrolytics in it. I got the thing going but broke a screw in the tuning capacitor.

[AllAmericanFiveRadio]

I'm glad you got the radio working. But what a bummer about the broken screw, I hope you were able to work around the problem. When I'm working on a customer's radio, I'm extra cautious. It is amazing that I not more paranoid then I am.

[ncautoman57]

Great video. I have rebuilt many Zeniths and you're right on. Rich

[AllAmericanFiveRadio]

Thanks. It is interesting working on early radios. The audio quality on some of the sets is surprising and can surpass a lot stuff made today.

[jefferyb304]

I was reading from a set of books printed circa 1965 titled practical handyman's encyclopedia telling about vacuum tubes so small that 3 could fit in a thimble

[AllAmericanFiveRadio]

Yes, they are so small one was used in a hearing-aid. coolbluelights has asked me if I have a radio using subminiature tubes. I did have, but I gave it to a good friend. He put in a lot of editing work on my new book, but refused money for the work. He did a terrific job!! So I sent him a few very nice radios for his work. An Emerson highbred (sub-miniature tubes and transistors) was one of the radios I sent to him.

[tubeie07]

Again another superb watch! thanks for posting this classic... Your lucky to have 2 of them.

[AllAmericanFiveRadio]

Thanks tubeie07. Yes I was very lucky to find one at the Raleigh Flea Market. I could not believe it. It was quite a challenge staying calm and not ripping out my pocket when I paid the vender.

[mariopica]

Formidável!! Wonderful. Thank you very much for sharing.

[AllAmericanFiveRadio]

Thanks so much mariopica and your welcome. I'm going to do a few videos on the signal-tracer, how to build one, how and why it works, and how to use it. But maybe not in that order.

[damusician]

awesome! that signal tracer looks handy. i wonder where i can find one? anyway i think pcb came out in the late 50's or early 60's. i have a 1966 voice of music tube record player. the chassis is on a printed circuit board, but it need work due to low volume.

[AllAmericanFiveRadio]

I'll come up with an inexpensive design soon.

In my new book, on page 133, I discuss how to build a signal-tracer and on the next page, using the signal-tracer. I put that video of my new book in my Playlist. I'm planning on making a video on signal tracing, it is a very useful tool.

[coolbluelights]

Did you build that signal tracer? looks handy, I could really use one! :)

[damusician]

me too! i wonder where i can find one? sound like fun!

[AllAmericanFiveRadio]

Oh yes, it is very useful. I did not build that one, but in my new book, on page 133, I discuss how to build a signal-tracer and on the next page, using the signal-tracer. I put that video of my new book in my Playlist. I'm planning on making a video on signal tracing, it is a very useful tool.