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Hengist · 2nd Feb 2019, 6:35 pm

Hello Mike
For the driver transformer I used an original Repanco TT20 (measured turns ratio 22:1) which was intended for this role. For the output transformer I used the low impedance secondary of the well known RS Universal Output transformer (still available) as an autotransformer with tappings A and D used for the load and tappings D and C connected to the 8 ohm speaker. I left the primary (high impedance) side disconnected. This gave me an impedance ratio of about 4:1 which worked nicely, but left the speaker with a constant 9ma of DC current. I felt I could live with that.

2nd Feb 2019, 6:35 pm	#18
Hengist Triode Join Date: Feb 2014 Location: London, UK. Posts: 20	Re: Radionic Regen Hello Mike For the driver transformer I used an original Repanco TT20 (measured turns ratio 22:1) which was intended for this role. For the output transformer I used the low impedance secondary of the well known RS Universal Output transformer (still available) as an autotransformer with tappings A and D used for the load and tappings D and C connected to the 8 ohm speaker. I left the primary (high impedance) side disconnected. This gave me an impedance ratio of about 4:1 which worked nicely, but left the speaker with a constant 9ma of DC current. I felt I could live with that. __________________ Regards, Tim