View Full Version : CTC-15 horiz sweep adjustment


Bobby Brady
07-18-2006, 10:38 PM
I am preparing to do this and my Sam's says I need a 0-500MA meter and a 0-1500 microammeter.
Would the two meters I have pictured here do it properly?
The RCA meter ia a 0-1000 and I think that should be fine as I measure for 850 but Sam's says a 0-1500. Is this a dumb question? I suspect so but I want to be extra sure so I don't fry the flyback.
Is there a special stuff to lock the coil slug? Could I put a spot of candle wax on it?
Thanks for looking.

blue_lateral
07-18-2006, 10:53 PM
To use ammeters for this you must break the circuit, and on some sets RCA did a nice thing and put 1K resistors in the cathode circuits of the 6je6 and the 6bk4. You can hook DVM's across them and take the readings in volts, without unsoldering anything. Just make sure the resistors are still 1k, for the sake of accuracy.

Going completely from memory, 850 sounds a little low for the 6bk4. Is that right? Anyway, going slightly high on this within reason might not be all bad. You want the H.O. current as low as possible, though.

I dont think I would try to lock the coil. I have heard more than one horror story right here about the fragile old coil disintegrating when someone tried to adjust it.

John

reeferman
07-18-2006, 10:58 PM
It's been a long time, but as I recall, there was a wire close to the H.O. tube socket that could be disconnected for current measurement. If memory serves me correctly, I put a #47 bulb in series and adjusted for minimum brightness on the bulb. It's been a long time. Don't do anything to lock the coil.