Repairing Two Vintage Pocket Transistor Radios Zenith Royal 50 And Continental

[@tkempke]

To answer some questions. This Zenith is my radio. Purchased from a yard sale recently for a couple of bucks. When I opened it, it did not appear anyone had been in it. The electrolytic showed shorted, so I replaced it. I did not touch any of the cores or trimmers, which proves I was very wrong in assuming no one had been there before me. I believe that I said in the package that the Continental was the important one. Personally, we’re I Shango, I would have EOLed the Zenith by heaving it against a brick wall. Much credit is due to his persistence and many thanks for taking on these two radios.

[@_Ramen-Vac_]

I always either use a 1 wood, about a 4-iron, or, on a really sunny day, throw it up and it's a homer. -thousand pieces gets the grand slam.

[@danmackintosh6325]

@@_Ramen-Vac_ you should try some Cricket, might be able to bury chunks of component lead in the bat if you swing hard enough

[@RoughJustice2k18]

*Thomas Kempke* - never assume the inside of vintage electronics is "virgin territory" (untouched since it left the factory) as that is very rare. Some people tend to overestimate their skill level when it comes to these, thinking "it's got a little problem, I reckon I can fix it" (when they don't have the experience, proper tools, equipment or ability to accurately diagnose and repair these things with any degree of success) so by the time it ends up in the hands of a new owner, they will find springs, clips or screws missing, broken plastic, or bad solder-work. I've seen this many times with boomboxes (especially double cassette models) and portable multi-band radios and made the same incorrect assumption that they were virgin (or close to it).

[@batman4e]

Why EOL? That transformer can be changed with one from the Chinese kit.

[@johnnytacokleinschmidt515]

Can learn more from trying again after you give up and take a break.

[@tkempke]

It should also be noted that the capacitors in the Continental were bursting at the tops, so regardless of whatever else was wrong, they needed to be replaced. I've been in this business, on and off, for 50 years and I've certainly heard Shango and others state that bad caps seldom cause a radio to be dead. I will take full responsibility for getting the antenna wire in the wrong place and causing the other short in this radio. Thanks again, Shango

[@shango066]

Yeah they would usually be open or highly degraded at that age.

[@danmackintosh6325]

Credit to you for owning the mistakes, it's not easy working on stuff designed not to be serviced & am already noticing my eyes not being as sharp on tiny stuff at the tender age of 39 so you're not doing bad at all!

[@billace90]

I am the owner of a blue 1963 Realtone 9 transistor AM radio, made in Japan. To my knowledge the radio has never been serviced, but it has been with me for the last 10 years. Of course it runs on a 9 volt battery like most of those vintage transistor radios did back then. I am currently listening to the news with it. I find it amazing that 57 yesrs later it is still working, and with good reception and great volume. You hear the phrase “they don’t make them like that anymore”, but that’s an understatement!

[@uxwbill]

The grille on that Continental radio is striking.

[@barryfleischer6553]

Absolutely amazing skill and patience.

[@n2n8sda]

random "smokers choice" around 34mins made me spit out my coffee :D classic Shango

[@danmackintosh6325]

I miss Cracklepony MasterCharge :( Isn't smoker's choice kind of a "damned if you do, damned if you don't" thing? apt for how messed up that little Zenith was.

[@JerryEricsson]

When I was young, and still lived on the family farm, dad, who was the farmer began training me in the farming operation. One of the first things I learned was to take a screw driver and tighten all the screws on the equipment before we began to use it, be it a drill or a harrow, or sickle mower. I carried that over to my early radio repairs till I learned that screws in radios don't need to be tight!

[@AMStationEngineer]

To quote Doug, drh4683, the Zenith was a victim of "screwdriver drift"....

[@rittenhouseunit7604]

Let us never forget CHAZ. If we allow them to continue there might be a CHAZ near you some day.

[@qwertykeyboard5901]

fun fact: us marxist leninists dont aprove of chaz, ideological differences

[@2509498788]

Another entertaining show. I enjoy watching you figure these puzzles out. Giving me giggles along the way. Thanks again shangoo

[@TheRadiogeek]

That radio is one hot mess. Great job tracking down all the issues! 👍👏🏻❤️📻

[@tretowntret7541]

Supper radio o wielkiej czulosci odbioru firma ZENITH Jest supper

[@TrevorsBench]

Somebody fixed that Zenith previously by tightening all the loose screws

[@rogertycholiz2218]

Trevor - I was fortunate enough to get recently on eBay a Nippon Nipco 8 transistor portable radio. It's around 60 years old. Works just fine. It appears that it was never used. Paid $100.oo for this great little Nipco. Put in a fresh 9V battery and tightened all the loose screws.

[@waltschannel7465]

Well of course!!!! Can't have loose screws. Everybody knows that... Sheesh....

[@vjf2549]

Amazing how "like new" the topside of that Continental chassis looks compared to the ugly solder side of the printed circuit board. Great job. Thanks for the video.

[@call5sam]

As always, a great video! Gives me encouragement.

[@Hunter-xy6qq]

Great fixer upper video. Make more videos about street finds. Even the plumbing repairs are great.

[@ralphups7782]

The side with the tracks on it, looks like my handy work before I concede and pass it on to you guys. ;-7

[@nickfrench7372]

Sounds like u had done a nice job in getting that zenith vintage transistorised radio working well in the end,,,can't believe how the trimmers and the core transformers were out of alignment due to being tightened up? No wonder why the radio didn't receive any stations. I've only done realignment of cores and trimmer sensitivity by ear,,,on any radio I had received that had station and sound troubles,,,and found only a lot of dust and moisture inside,,,along with cracked dry solder joints too. No parts replaced,,,just cleaned and resoldered and re-aligned tuning cores and trimmers on the tuning capacitor,,,and the radio was working like a new one altogether. The owners couldn't believe how I had restored a few old vintage transistorised radios back into working order by doing a lot of tlc repairs,,,they paid me well,,,and very much never had trouble with the vintage transistorised radios again.

[@jsurfinreverbchristmassurf3560]

I had a continental just like that when I was a kid. I gave it to one of my cousins probably in the early 1960s. On the other side of the u.s. it worked excellently.

[@hattree]

I have one of those zenith royal 50's. Interestingly, mine has ones in round packages. My grandfather bought it new in 1960.

[@radiotvphononut]

Don't feel bad about the batteries. I've done the same thing, more than once, on a Zenith just like this.

[@ford1546]

if I remember correctly, it is the smallest camera you have that gives the best and most comfortable sound. I remember you said in a video that one camera has less good sound. I think it has the best sound!

[@alphabeets]

I wonder if it will get channel 6.

[@williamsquires3070]

(@15:20) - it looks like someone replaced the transistor (a.k.a. Microminiature vacuum bulb w/no filament) with something they thought was a transistor, but was - in fact - two diodes front-to-back. The tester confirms this, as the junction (1) is the cathode of one diode (1 to 3), and the anode of the other (1 to 2). An NPN would test as common-anode, and a PNP would test as common-cathode. Is there a part # on that thing? I doubt it crosses to any BJT in the NTE cross-reference guide. And if it does, then I’ve never seen that failure mode in a BJT before.

[@randyab9go188]

Golden screwdriver got ahold of the Zenith.

[@JrGoonior]

Yup! Beat me to it...

[@Rfk1966]

That Kinks tune still features the best guitar tone

[@Musicradio77Network]

11:40 is the same exact transistor radio that “radiotvphononut” has. But his has the original sticker on the back. This one does not. I used to have a little transistor radio and it was Stewart, and it was a small square and it fits right in the pocket. It was AM only, but it doesn’t have FM. It was lacking the band. I wonder if they might add a Bluetooth to these two units and it will play MP3 music on them if they will add a selector switch.

[@randyab9go188]

When I do an alignment I use a scope across the voice coil to find the peak. Some like to use a vtvm or a vom. I like the scope because sometimes at peak the waveform becomes distorted. I back of until the waveform becomes clean and no further. If I was stuck on a desert island and I could only take one instrument with me, it would be a scope & something to power it with.

[@billweyman7244]

i HAVE THE SAME RADIO EVEN SAYS MADE IN USA I BOUGHT IT FOR $3.00 AT A FARMERS MARKET 10 YEARS AGO STILL WORKS GREAT..

[@craignehring]

Interesting to be sure. When I get home I'm going to either sell some relic radios or try to fix them. I have too much "stuff" doing nothing

[@chuffpup]

Great thing about it (no 1) is the tartan (plaid) speaker grill.

[@chadcastagana9181]

25:41 I see, it uses two xsistors to create the RF-to-IF converter-stage in a LO and Mixer, not a single xsistor as in the more utilitarian Autodyne Converter. But why do that at all? 26:50 Only 75 degrees in Redondo Beach? 39:25 This pocket radio receiver has a truly unique battery connection and Vcc design?

[@gregorymalchuk272]

To be able to advertise more transistors.

[@fanofoldfans9238]

That 6 transistor with the look alike Irish Kilt should be playing bagpipes. And the Zenith just needs a NOS radio. But nice effort on that one.

[@rolandkeith5322]

Cool video as always

[@TKomoski]

Gas bloating in oily stools (can I use that in my book)?

[@XMguy]

Glen Campbell was amazing.

[@tectalabyss]

Hi shango. With sharing your video,I got lose in twitter land. Lol. So now I am re-watching your video. Liked,shared. All my best. Not A Bot : )

[@waltschannel7465]

25:20 Love Sounds! Ha! Didn't know LA had an elevator music station. Pretty cool actually... 😉 Weird that your Chinatester lost accuracy on those Ge transistors.

[@josephtaverna1287]

Great video

[@robmages]

I've got a Zenith Royal 50l that was my grandfather's. It's sentimental to me. I found it in a box that I've had for years. It had some corrosion on the battery connections that I've cleaned, but the radio is DEAD, nothing. Are you still doing repairs?? Rob, WB6CEL

[@ostermann6176]

For some reason this video is dated June 14th 2020 in an RSS feed. Has it been on hold or something?

[@Steveuk405]

The second set had the classic Man Made Fault and they are always hard to find! But as far as the Output Transformer goes - any similar one will do here. There is quite a bit of leeway here. A good one from a scrap board or from a Bangood Radio will probably do here.

[@Pawelr98]

A symmetrical power supply for such radios can be made using 4 silicon diodes and a resistor. 2 diodes have roughly 1.4V drop on them so about the same as AA battery. I often used zeners for making basic +-5V symmetrical power supplies in low power devices.

[@eDoc2020]

I would've just made a resistive divider with a pair of large 20 ohm resistors I have.

[@bill392]

So where are you finding the schematics for these radios? I have a few 40+yo beautiful little radios that I'd like to fix but I don't want to make the attempt until I have a schematic to follow. TIA.

[@robinsonsoto8471]

Nice troubleshooting..

[@electrofan7180]

Don't test old germanium transistors with that 'transistor tester' things. It often tests incorrectly due to high leakage currents. It was designed for modern silicon stuff. Results with germanium are pretty random.

[@werner.x]

That's true.

[@zulumax1]

Electro FAN, What about using the older analog meter testers for leakage and gain?

[@brigganthewolf1461]

About that speaker rattling against the grille, I have a Zenith Trans-Oceanic D7000Y that also rattles or distorts on the bass. However I'm not sure if it's the grille, considering I removed the original foam insert (which disintegrated to dust), or if it's amplifier distortion (the transistors are a matched pair, original to the radio, they put out 500mW into the 4x6 22 Ohm speaker). And that's when you have it at a moderate volume (about 1/4 on the volume knob). The speaker is in mint condition - no cracks, tears or anything out of the ordinary. Obviously I could adjust the tone control and reduce the rattling or whatever it is, but it's going to continue to persist.

[@Gutterball]

how does a converter differ from the zenith oscillator mixer configuration. I have heard the mixer also called a converter.

[@cfd_novotroitsk]

Horizontal oscillator coil?! I guess this is a flashback from that crusty CTC16.

[@CATech1138]

horizontal oscillator coils... useful for decoupling vertically polarized AM...snicker

[@weerobot]

Very Cool...

[@ralphups7782]

About the transistor shipments, I would hang on in there. My eBay shipments were delayed quite badly, but this past week the Post workers had their work cut out. In you're case you might get a bottle of vodka as compensation for the delays as well as your goods. :-)

[@drfalcon4102]

My brother had a Zenith, just like that one, was a great radio till we were camping, and got hit with a mild flood, think its in the Indian river

[@tiporari]

Nice diagnostics. Well done. Who knew you didn't just tighten the coils until they snapped 😂

[@russellhltn1396]

Odds are the transformer opened up right were the winding connected to the leads. It's not likely to burn out. Might be worth touching it with an iron to see if heat will fix it. It might be fixable - if you have the hands of a surgeon.

[@Kopter6]

I really like your repair videos. I got a question, could a Russian MP38 be used as a substitute for a 2n168A (Germanium NPN) it's used as a converter in a small portable AM Radio. -Tom

[@shango066]

I don't think the MP series goes up fast enough, most of those would be the 1T series

[@Kopter6]

@@shango066 Good Info, reason I ask it claims MP38 Freq. 2MHz. I thought it might be ok for the AM broadcast band. The NTE101 looks like it might work but they are pricey, the NTE101 packaging bag says Ft: 5MHz . Can you recommend an 1T # that could fit the bill?

[@saintleibowitz8401]

what do you mean by transformer wax? is it a paraffin mix? i have a pyramid capacitor bridge whose transformer needs to be re potted

[@scharkalvin]

2n404 is a computer switching transistor, useful at the BCB. Only one station, sound like the IF's are WAY off freq, and the converter isn't working, IE: it turned into a one station TRF.

[@ichigo_varactor358]

In essence, a bipolar transistor is two diodes connected together. I wonder if those transistors have just degraded enough to confuse the tester

[@CATech1138]

nah....i used to think that too, but hooking 2 diodes neg to neg doesn't mimic a pnp transistor....no matter what you on the neg connection current will not flow from pos to pos....what ever those transistors are doing there is some sort of electrical seperation in the base region of the material...but germanium does do strange things and the $6 tester was not capable of giving correct results....no matter how they test, they do work..

[@piwex69]

This component testers work reliably from 9V battery. Never have seen such for 5V supply. Maybe this explains 2xdiode reading.

[@asbestomolesto]

I see sometimes today's transistor testers have a hard time checking germanium transistor, and sometime they show up as diodes. Can that be the case?

[@shango066]

Dynacube lorber Mobile Trailer

[@asbestomolesto]

@@shango066 Ehm, I don't get it but OK :)

[@jazbell7]

Everyone know that you have to tighten all loose screws, even those ones in the funny holes.

[@chrisa2735-h3z]

Sadly I feel like electronics will never be made this well again :(

[@waltschannel7465]

Electronics started going downhill the day after this Zenith set was built.

[@qwertykeyboard5901]

Some are still well built

[@jackhreha4907]

I rember that raido at the 1962 seattle world's fair. Centry 21.

[@StoneShards]

I image their manufacturing process might have dictated a socketed transistor, perhaps to avoid heat damage during manufacture. It was located in a heavy duty part of the board...

[@robinsonsoto8471]

Question: How can you get audio with IF????. IT must be after the detector.

[@hugh007]

Signal tracer can demod the IF

[@robinsonsoto8471]

Wow. Thanks.

[@hugh007]

Thy frequently have a small signal diode in the probe. Maybe a 1N34.

[@robinsonsoto8471]

@@hugh007 Thanks for sharing,

[@rwdplz1]

It's amazing you can actually find schematics for these little antique radios

[@jw200]

Old radios and other things almost always came with full schematics included.

[@tkempke]

These happened to be Sams Photofact’s which are available online.

[@markmarkofkane8167]

You work magic. It looked like a trashed circuit board. (First Radio) But you got to work like new.

[@ronaldkrugman8074]

So sorry. Yes it is out there. But where.

[@rogertyler3237]

That Radio Is a Keeper.

[@SquantoTerror]

Transistor gas bloating and oily stool 37:23

[@kermitmawyer1743]

The man 1

[@HiFiasco]

Those transistors only work with good vibes. Next time try tricking them with sweet talk, words of approval, thumbs up and love songs!

[@craignehring]

And award them a trophy 🏆

[@CLUBNEON-m6i]

I don't understand why people think that changing capacitors would always fix everything, specially when it's all corroded like that

[@Synthematix]

Probably because leaking capacitors destroy circuit boards

[@mikelatoski2347]

"I wanna be a sanitation czar!"

[@KameraShy]

MeToo

[@perrymckinney6146]

Am radio is just about dead. Not many stations that broadcast music on am anymore, mostly talk radio and news. Was cool in the 80s when am stereo was around, sadly it died. I still have my cquam recievers and have an am stereo transmitter that i show others what was once reality.

[@brianleeper5737]

A lot of factory car stereos supported AM stereo, but it was never advertised. I don't think the owners manual even mentioned it. The 1986 Dodge Omni that was my first car apparently had a radio that supported AM stereo, but I never knew it till later.

[@bro.weaver1282]

What is WORSE is they are piping in stereo music from FM! AM sounds great with MONO music.

[@nickfrench7372]

@@bro.weaver1282 In Australia I used to get am stereo in very clear sound form,,,from an am radio station that was nearly 200 klms away,,,wish I still had heard that 2day. Now the same station is on fm stereo,,,I don't always receive it that good,,,compared to am stereo back in those old days.

[@blackarm3265]

How did you learn all this electric and circuit board stuff I always thought reading wiring scamatics was a little tricky any way love checking out all the knowledge pooring out of this channel take care bro🤙🇺🇸

[@boomer9900]

I could never get good with those SCR horizontal outputs on those RCA's

[@dougmcartin3881]

Being that this is a fairly common radio and given the poor cosmetic condition it really wasn't worth putting in that much time and effort to repair it. Then, after all that, to find a bad transformer in the audio stage was the final insult. As an educational video of course its always valuable.

[@brianfletcher9774]

Rush Limbaugh dump.... I damn near spewed my soda !

[@ugurylmaz7666]

👏🏻👏🏻👏🏻👏🏻

[@matthiasmartin1975]

"There's no fixing that transformer" - Huh? It's just wires on an iron core! Put a new wire on there and it's fixed. BTW, you misspelled "eerily" in the video description ;-).

[@dalerobinsuk]

Those atmel based "Transistor Testers / LCR meters" are very hit and miss with germanium transistors.

[@krazytrinisteve]

Why the name aha go?

[@Radiowild]

Five "O" clock Charlie at 26:32.

[@hotboiorlando]

what is chaz?

[@nathanlewis5682]

Acronym for capital hill autonomous zone. Communist camp occupation around downtown Seattle during the early days of the start of the riots.

[@hotboiorlando]

@@nathanlewis5682 ok

[@canuhonk7433]

@25.19. Chris Pootay's Love Songs/ Very sesual.

[@justsumguy2u]

That's so wierd to see a bad transformer in a solid state pocket radio. There really isn't enough voltage or surge current to burn out a winding. I would cite oxidation as a possible cause, but the rest of the radio doesn't appear to suffer from it

[@guitarpro248]

"the battery wasn't in there I swear" *board all corroded and traces falling apart*

[@CoreyDeWalt]

The alignment at the end went Pentecostal for a second.

[@chadcastagana9181]

U mean 'Evangelical'

[@JoJoGunn1956]

@@chadcastagana9181 No, he said Pentecostal, and he was correct.

[@aarongunter5582]

Ding dong Dingdong Dingdong lol 😂

[@annaplojharova1400]

This tester just seems to get too easily confused by the larger reverse leakage currents of Ge transistors. Sometimes it just display way too high gain (it measures it just as a plain dc Ic/Ib, instead of differential deltaIc/deltaIb), but sometimes it just misidentifies the component at all and shows nonsense...

[@_Ramen-Vac_]

save the Zenith coat-of-arms badge and the transistors and shite-cane it.

[@rickjohnson1632]

👍👍

[@chetpomeroy1399]

I find that re-soldering the litz wire from those antenna coils back to their pads on the chassis is a real pain.

[@vancouverman4313]

Since Litz wire is just thin little strands of enameled copper wire stranded together all you need to do to make it easy to solder is to burn off the enamel with a match or lighter and then gently clean the copper off with a piece of steel wool or fine sandpaper. Once the copper is shiny, tin the end with solder and solder to the circuit board.

[@ronaldkrugman8074]

Give me a clue!

[@jamesv833]

6:25 Ric Edelman

[@neil6958]

👍

[@ibrahimkocaalioglu]

you used 3v battery instead of 1.5v

[@billmcdonald2436]

(Chasing a screwed up alignment!) lmao

[@saintleibowitz8401]

yowza now thats a gnarly looking circuit board... or maybe i'm just young.