Tube Radio Restoration

[ssjones]

My father in law had a full tv/radio shop in his basement, from a side gig he did in the 1970's. He passed away last year, I tried to sell all the components and thousands of parts, but got no takers. (Facebook Marketplace and Craigslist). We finally had a junk guy pick it all up. Sad.

 

[AppalachianPipe92]

Looks like something at my audio repair man's shop. He loves old tube radio restorations. He just maintains my amps and turntables for the cash. I've actually sat with him the past few times and watched him work. Really wish I understood the schematics more and could work on my own gear. A recap is the furthest I've gone with my own work.
This is a topic that gets me just as excited as pipes though. I love audio and hifi. Great post man! Cool to see other preserving these magnificent machines

 

[daveinlax]

There was a Bakelite smokers radio with a built in pipe rack and ashtray in the silent auction in Chicago that I don’t think got any bids.

 

[bullet08]

By the time I was making radios for fun, transistors were used instead of tubes. That was mid 70s. I knew big TV consoles and things had tubes, but never got to play with 'em.

 

[mingc]

Here still a lot of old stock vacuum tubes around. Some particular types are higher priced and limited in a availability due to the popularity/use of the type in certain products.

I bought a quantity of old stock tubes 20 years ago, and prices nowadays are up considerably fo some.

Old design tubes popular for audio applications ate still manufactured, mostly in Russia. There has been trouble importing those in the last few months. I read an article the other day about a boutique tube mfr in the US looking to expand their products to cover that.

About 20 years ago, I dabbled with DIY tube amps but it got kind of expensive with teflon sockets and NOS tubes that kept getting more and more expensive. And then life and kids got in the way. I now see from Google that someone has resurrected the old Western Electric tube company and it's selling new production 300B tubes made in the USA for $700 each. Yikes!

 

[craig61a]

My father in law had a full tv/radio shop in his basement, from a side gig he did in the 1970's. He passed away last year, I tried to sell all the components and thousands of parts, but got no takers. (Facebook Marketplace and Craigslist). We finally had a junk guy pick it all up. Sad.

There are a few online vendors that specialize in that sort of thing, but just like pipes, it’s a relatively small group of people that are into that sort of thing. And if you’re not in that world, most people aren’t interested in that type of stuff.

 

[craig61a]

About 20 years ago, I dabbled with DIY tube amps but it got kind of expensive with teflon sockets and NOS tubes that kept getting more and more expensive. And then life and kids got in the way. I now see from Google that someone has resurrected the old Western Electric tube company and it's selling new production 300B tubes made in the USA for $700 each. Yikes!

There are plenty of older amp tubes that could be used in place of the 300B that would be less expensive, and have that same general shape.

I think the attraction is the shape of the tube. It may be that the 300B has higher plate dissipation. I’m not going to dig out the RCA tube manual right now…

This 41 would fill the bill. Plate dissipation is lower, but I think you can follow where I’m going with this…

 

[CoffeeAndBourbon]

Looks like something at my audio repair man's shop. He loves old tube radio restorations. He just maintains my amps and turntables for the cash. I've actually sat with him the past few times and watched him work. Really wish I understood the schematics more and could work on my own gear. A recap is the furthest I've gone with my own work.
This is a topic that gets me just as excited as pipes though. I love audio and hifi. Great post man! Cool to see other preserving these magnificent machines View attachment 154073

I see some Klipsch speakers!!

 

[renfield]

Not necessarily… The AC side will run through the filaments. DC is built up on the filter caps, and since the AA5’s mostly used a half wave rectifier you won’t have the same potential as one that uses a ct transformer.

Run it through an isolation transformer and keep one hand in your pocket while it’s live…

The older AA5s had the chassis wired to hot and there were a lot of variations before they finally got a ground bus (sorry if you already know this). This one is somewhere in between.

Good points on working with tubes. The one hand rule especially. Also remembering to bleed the caps before poking around. I’ve built a few guitar amps with an unloaded B+ around 600V. I’ve learned the meaning of the words caution and respect, fortunately not the hard way.

 

[bayareabriar]

It looks interesting. I’m into HiFi, but that mainly composes of Naim Audio equipment. I‘m more into this sort of stuff, not so much the internal technicalities.

 

[mawnansmiff]

My late Father was demobbed from the Royal Signals in 1946 and one of the first things he bought upon getting home was a Murphy A104 receiver, more commonly know as a Murphy 'baffle set'.

Medium wave, long wave and short wave with bandspread (the bit that looks like a mini TV screen) with the huge speaker placed in the centre, this set sounds fantastic.

It fell into my hands about 25 years ago and as it hadn't been used for many years I decided to strip it down and check it out. BTW this has valves (tubes) the size of half pint beer glasses!

Long story short, after cleaning the inside of the glass tuning scale and the magnifying lens & window of the bandspread and replacing the old cotton wound rubber mains lead it fired up a treat. A few sprays of contact cleaner in the switches & pots were the final touches.

Now it sits on a dresser in my bedroom gathering dust



I also have a few valved (tubed) communications receivers that are all fully functional.

Regards,

Jay.

 

[renfield]

That is beautiful. Apart from caps and some resistors going bad those old sets can be really robust.

These days few consumer products are designed with a sense of style.

I also like the term “valve”. So much more descriptive than “tube” for what they frequently do in a circuit.

 

[mawnansmiff]

That is beautiful. Apart from caps and some resistors going bad those old sets can be really robust.

These days few consumer products are designed with a sense of style.

I also like the term “valve”. So much more descriptive than “tube” for what they frequently do in a circuit.

Yes, back then things were built to last and last they did. A few of the caps were also replaced as they were showing signs of throwing in the towel. All components back then were huge so working on these old sets is usually a doddle.

With none of the built in obsolescence we get nowadays, I wouldn't be at all surprised if my old man's set was still working in 2046 when it would be 100 years old.

Regards,

Jay.

 

[Python 357]

I am a Ham operator,N3EUL,ex USMC operator,and restore old radio wooden cabinets.