OT for Airline amp

[angelodp]

Hi I want to replace the OT on my Airline 9015A. It has 325 Plate Voltage.

I have a donor OT from a Rowe Jukebox. The turns ratio of the Yellow to White wire is 24:1 which when squared gives me 576. The Airline uses 2 6L6GC tubes and wants to see 6600 EL for PP.

6600/576 = 11.5 ohms ....

I this then not useable with the Airline amp at 8ohms or 16 ohms?


The schematic for this OT shows a turns ratio of 27:1 but when I apply voltage I get 24:1?

A

[martin manning]

I have no idea what yellow and white means... assuming it's a p-p OT, are those the plate leads? The 24:1 vs 27:1 could just be the error in the simple test. I would say that OT would be fine with a 8 ohm speaker.

ok, I see you added a schematic. E1 and E4 for 8 ohm output with 27:1. You'll have 5k8.

[angelodp]

Sorry, that was a bit obtuse. Here is the donor amp. Should be ok for PP 6L6GC @ 325v on plate?

[martin manning]

Yes, I think that will be ok.

[angelodp]

Martin I rechecked my ratio readings and I reversed the feed with voltage going into the primary side until I get 1 volt on the secondary side and it confirms a 24:1 ratio. Schematic says 27:1

Can you explain the discrepancy, will it matter.

[martin manning]

It won't matter. The voltage measurement technique is not exact, and you are within about 10% 24/27=0.89

[angelodp]

Thanks Martin.

A