I have rather interesting issue with the output stage of one of the devices I'm working on right now. I've atached the schematic of the output stage below. Output transformer is CineMag CMOQ-2
Here's the problem. When I connect the transformer in 1:1 configuration, everyting is fine. However, when I connect the transformer in 1:2 step-up configuration, I get a huge oscillation on the output at 300 kHz, several volts amplitude. I even tried 1:3 configuration and got the same oscillation, but at 150 kHz. 600R resistor on the secondaries doesn't help.
Why would that be? What can be done to cure that? I really need a transformer t work as 1:2 step-up here.
Here's the problem. When I connect the transformer in 1:1 configuration, everyting is fine. However, when I connect the transformer in 1:2 step-up configuration, I get a huge oscillation on the output at 300 kHz, several volts amplitude. I even tried 1:3 configuration and got the same oscillation, but at 150 kHz. 600R resistor on the secondaries doesn't help.
Why would that be? What can be done to cure that? I really need a transformer t work as 1:2 step-up here.