I bought a T-368C HF transmitter project back in October, 2007 for $1575.42, and finally started seriously working on it a couple months or so ago. This evening, it got its first taste of power in many years! It’s semi-alive, but needs more work:
- No actual smoke seen; just a healthy (?) amount of “hot dusty stuff” smell.
- I can’t seem to get the PA to load up at 150mA in tuning mode as the manual directs; tuning for max RF output gives me about 100mA plate current and 65-70 watts of RF.
- Full power mode is no-go: I hear some arcing sounds, then the overload relay trips.
- Both blowers work, though the PA blower is quiet enough that I can’t hear it over the cabinet blower.
- PA grid drive reads a bit high at 15mA.
- Int. amp plate current reads 25mA.
- In AM, I can only get the modulator bias current up to around 40mA. I don’t trust the bias potentiometer based on DMM testing earlier today. Whistling into the mac doesn’t swing the meter higher.
- The filament voltage meter is a bit sticky; I need to thump on it to see small changes in voltage.
- I don’t like having the back cover interlock defeated during testing, but those big tubes sure are pretty when they’re all lit up!
It’ll take more work before I’m running my T-368C on the air, but it’s great to see some good signs of life from it!