Hi All! I have some rare (probably noncommercial)radio and disc player equipment. It has the following tubes: 5Y3 - 12SA7 - 2*12K7 - 12Q7 - 2*7B5.
Probably the 12SA7 was installed in a modification from 12A7 replacement (not sure).
I've never seen before a mix between octal and loctal tubes, this is the firt time.
Any schematic will be welcomed!!

Thanks in advance
Carlos from Argntina

I don't know what this set is, but you will find, from time to time, sets with a mix of octal and loktal tubes, or even other types (octal and 7 pin, octal and standard base, etc.). Zenith and Philco often mixed types, as both manufacturers were keen on loktals. Many Zenith portables and some Zenith consoles used varying mixes of the two 8 pin types. Also some 'off-brand' radios mixed types as well.

I am guessing that the radio has a 12.6 volt filament winding, and that the two 7B5 tubes' heaters are wired in series. I believe I read in my Sylvania tube manual that the 7B5 is a loktal equivalent to the 6V6.

Is there any manufacturer names on the tubes? Any identifying model numbers printed or stamped on the chassis or cabinet?

:I don't know what this set is, but you will find, from time to time, sets with a mix of octal and loktal tubes, or even other types (octal and 7 pin, octal and standard base, etc.). Zenith and Philco often mixed types, as both manufacturers were keen on loktals. Many Zenith portables and some Zenith consoles used varying mixes of the two 8 pin types. Also some 'off-brand' radios mixed types as well.
:
:I am guessing that the radio has a 12.6 volt filament winding, and that the two 7B5 tubes' heaters are wired in series. I believe I read in my Sylvania tube manual that the 7B5 is a loktal equivalent to the 6V6.
: