Ultra V1770 - my first telly and Im struggling

[Exiled Yorkshireman]

Hunts  etc (composite or card case) everywhere.
See what DC HT volts and  heater chain volts there are.
The HV ceramics on LOPT stage can fail.

Though I last worked on these in 1970s!

I think 1959, so almost all caps of 1nF or more are suspect. Electrolytics of this era often reform if seal intact. No leakage current means it's dried out.

but the minimum stable frequency is about 6.7kHz.

Shouldn't it be 10.125 kHz?  405 lines x 25 fps, though 50 Hz and 202.5 lines interlace to get 405.

Thanks very much for replying, Mike. I think I've got all the Hunts other than in the IF and tuner. Sadly the main (triple) cap was totally dead, Measures a few nF per section. restuffing beckons. I'll measure HT volts and heater chain and report back.

I'm confused  about the line and frame osc frequencies. The manufacturer's service sheets show waveforms and quote 25 Hz for frame and 5 kHz for line, but you're right, of course. It's 50 Hz for frame and 10 kHz for line, or a tad lower for each when free running surely?