Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on May 07, 2012, 11:36:22 pm

Title: Valve Radio's as amps
Post by: TIMBO on May 07, 2012, 11:36:22 pm

Hi guys, Found a Astor valve radio,maybe about 1950s in a secondhand shop and was wondering if they make good amps. I can't find a schem but from the info i found is that it might have a 6v6 in it. The outer case seems in OK condition and @ $65 would it be worth the buy. Thanks

Title: Re: Valve Radio's as amps
Post by: kagliostro on May 08, 2012, 12:07:32 am

If the radio is nice and in good condition may be you want to build a little transmitter to be connected to the guitar

so you'll have your radio and also you can use it as an amp

http://www.leradiodisophie.it/Trasmettitore-om.html (http://www.leradiodisophie.it/Trasmettitore-om.html)

http://www.leradiodisophie.it/Downloads/Loria-02.pdf (http://www.leradiodisophie.it/Downloads/Loria-02.pdf)

http://www.leradiodisophie.it/Downloads/Loria-01.pdf (http://www.leradiodisophie.it/Downloads/Loria-01.pdf)

http://www.leradiodisophie.it/Circ-oscill.html (http://www.leradiodisophie.it/Circ-oscill.html)

http://www.leradiodisophie.it/Bobine.html (http://www.leradiodisophie.it/Bobine.html)

Note that the transmitter need a high input signal, you can't connect directly your guitar

Kagliostro

Title: Re: Valve Radio's as amps
Post by: PRR on May 08, 2012, 07:17:47 pm

Does it have a power transformer?

If so, it's possible (tho $65 is not cheap).

If not, then it's a death-trap when modded for electric guitar input.

If it works, you _can_ use an AM transmitter to get signal in safely, but the trouble is not worth the quality.

Title: Re: Valve Radio's as amps
Post by: TIMBO on May 09, 2012, 01:21:39 am

The shopkeeper must have odd hours cause every time i drop in to have a better look, he's not open  :cussing:

Title: Re: Valve Radio's as amps
Post by: 12bz7 on May 09, 2012, 05:29:22 am

Quote from: TIMBO on May 09, 2012, 01:21:39 am

The shopkeeper must have odd hours cause every time i drop in to have a better look, he's not open  :cussing:

I would try ebay. I've bought many Astors, Mullards etc and only paid $5-10 depending on condition and if they work or not. Nearly all Australian radios (or all I know of) do have a PT. I've only ever seen USA radios without. I built a vibrochamp from the PT of an Astor for a friend a few years ago only because it was beyond restoration otherwise I wouldn't have the heart. Most of the small aus table radios are 5 valve with roughly 2amp filament current and enough B+ for a SE 6V6 or EL84. Most have
oddball valves, never seen one with a 6V6 or EL84 or 12ax7 for that matter. The only real usable part is the PT unless you want to recycle some caps and valve bases. You could probably convert one to use for guitar but I think you'll be disappointed with the sound. Hope that helps.

Title: Re: Valve Radio's as amps
Post by: TIMBO on May 09, 2012, 02:39:50 pm

Thanks guy's,Just didn't want a valve something go all rusty and dusty on shelf. Anything valve here in OZ are like hens teeth so you want to grab it when you can. I remember when i was a kid finding a valve radio and thinking that if it makes sound, it might make a good amp (always a tinkerer) So god only knows what i had plugged into it cause i didn't have a guitar then. I had it setup in my mothers kitchen and when i flicked the switch it lit up like a Xmas tree (like a Xmas tree on fire) quickly turned it off and through it in the bin.It is always good to learn lessons when you are young cause they stick with you for the rest of your life, so don't play with S***T you don't understand.Thanks :icon_biggrin: