[RodB]

A friend gave me this Eico 232 VTVM and I'm having trouble locating the schematic for it. This one seems to be a later version because it has solid state diodes to replace the 6AL5 duo diode tube. I would say maybe early 60s. All my searches have resulted in the schematic for a 12AU7 and 6AL5 configuration. This one has only a 6FQ7/6CG7 replacing the 12AU7. Any help is appreciated.

   
   

[morzh]

Is that a battery holder?

[Chas]

Try BAMA for a schematic.

Looks like a replacement power source for the D battery has been installed. The tube may be a sub for the 12AU7. As long as it balances and is stable should be fine. 

Was the Uniprobe provided?

Chas

[RodB]

It's a microwave antenna. ?;-p?. I substituted 1N4002s off the 6.3 vac winding for the 1.5 volt battery. Uniprobe is there. BAMA has the older schematic. I haven't looked up the tube yet, it has two sections but it's a 6 volt tube. I guess I'll wing it for now.

[Trog1058]

I have both battery and tube replacement modes
attached are the manuals

[Joe Rossi]

Looks like someone put the 6FQ7 in because it fit? 

[RodB]

I don't have it open but as I remember, the 6AL5 tube socket is missing and replaced with two diodes. The 6FQ7 twin triode looks like a good replacement for the 12AU7. The docs provided earlier are not matching this version as they have a different meter movement and the 6AL5 tube.

[TV MAN]

6FQ7 is a common replacement. Probably owned by a TV guy and those were very common TV tubes. I think I even have a note on my Eico sig gen that says a 6CG7 will help the performance, but never did the swap. I think I have the twin to yours and if I can easily find it, I can take a look inside and see what is glowing.