Reusing Magnavox 9300 series OPTs for other amps

[markmcmuz]

I have a set of these I took off my 9300 series when I did the DG modification. I acquired another one and will be switching them for the Dynakit 35 transformers. So I am curious what can I do with these take-offs. I know that they are a different impedance than the 175/185 Magnavox OPTs but would it be worth exploring? Has anyone done this?

 

[cademan]

You will have to look up "tube data sheets" and see what transformers can be used with the 6BQ5/EL84 tubes. You would look at push pull plate to plate ohms ratings.

6BQ5 has a plate to plate ohms of 8000
6L6GC has 5000
6V6GT has 8000 so they might work.

 

[gadget73]

6k6 tubes want a 12k load, which is in the ballpark of what you'd get from these transformers connected to an 8 ohm speaker.

 

[thorpej]

FWIW, I find that these output transformers are pretty decent for small-power guitar amp duty.

 

[Kidmoe]

Actually, My 9300 output transformers measured almost exactly the same as my 185 ones. Both were right around 7.6K into 4 ohms. The 8802 transformers on the other hand were closer to 10K into 4 ohms. I've only measured one set of 185 trannies though so cannot claim that as a truism for all samples.

I know that they are a different impedance than the 175/185 Magnavox OPTs but would it be worth exploring?

 

[gadget73]

7.6k would be 14.2k into 8 ohms, so even less of a mismatch than I expected for 6k6 tubes.

 

[markmcmuz]

Sounds like it is worth looking into. Just have to finish my second 9300 DG mod and a 8600 DG mod and I'll try it. I'm in need of an intervention.

 

[Blackdog61]

Just brought home anther 9300. If I don’t get to it this year it will get flipped.