Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Banjan73 on January 21, 2026, 07:51:50 pm

Title: Battery powered germanuim transistor travel amp
Post by: Banjan73 on January 21, 2026, 07:51:50 pm
Hi.
Here`s one more project I had the last years. This is not a tube amp, so please delete this if it`s not relevant/aloud here ;-)
The background on this amp was that I bought myself a travel guitar. So again, when traveling with my motorcycle, I needed a small amp powered by batteries.
I once built a clone of the "beano boost" with a Germanium transistor and I love the sound of this one.So therefore, this time I decided just to use the amplifier of a old radio. I ended up buying an old Norwegian "Radionette kurer transi" from 1958 which uses OC74/OC75 transistors, and slaughtered it (with a little tears in my eyes, off course). 
I found the schematics on the internett, and it`s attached. The amplifier part is circled. Looks almost similar to a tube amp?
Anyway, the connections where pretty easy. The loudspeaker is the one from the radio. So I built a cabinet to this thing. The input jack works as an on/off button just like an effects pedal.
Sound? Pretty cool. With a tube screamer in front, thisone screams pretty good! Nice practice amp.
Title: Re: Battery powered germanuim transistor travel amp
Post by: Banjan73 on January 21, 2026, 07:56:35 pm
Heres my collection of home built (minus the "two channel class A" thing) so far:
Threads are:
-This one
-Champ-ish "pocket" amp
-High gain two channel EL84 guitar amp
Title: Re: Battery powered germanuim transistor travel amp
Post by: Banjan73 on January 21, 2026, 08:02:36 pm
Oh!
I found a picture of the internal of the amp:
Title: Re: Battery powered germanuim transistor travel amp
Post by: roarshock on January 21, 2026, 10:58:40 pm
That's cool! There's an Italian cat that posts to reddit every once in a while that makes amps out of old transistor radios. I like small amps, so keep them coming!