Rca?

[DaveWM]

roger will do. Thanks for the input.

[DaveWM]

Oh I did find the year made 1977, still could not find the CTC number anywhere else, it was stamped but the stamp is too far gone to read

[Gunslinger]

do you have the model number off the back? A pix of the front of the set? serial number? chassis # is stamped on the chassis in blue print. also, in the front of the chassis near the small ckt board there may be a small label with the chassis number. The video board ..is it a 001 or 002?

[DaveWM]

oh well that was fun. Back to ticking. I heard it try to start up, then is shut down and not ticking again. I am trying to find the 27v souce to check. More pics coming and model numbers as well

[dieseljeep]

Originally Posted by DaveWM

oh well that was fun. Back to ticking. I heard it try to start up, then is shut down and not ticking again. I am trying to find the 27v souce to check. More pics coming and model numbers as well

I always plug it into a variac set at about 90 volts and see if it will start. Possibly, it will be easier to trouble shoot.

[DaveWM]

CTC-86 (it was on a pasted on sheet). It will come on for a second then cut off (you can hear the audio).

[DaveWM]

well other than the pilot light and the deguasse its dead as a door nail now.

it was coming on for a few seconds then shutting down, but now I seems to lack any B+ anywhere. Guess I will pull the chassis out and check around again. The fuse off the power supply board (right at the interconnect is still in place but seems to have sagged a bit in the middle.

I would be nice to be able to work on the chassis on the bench to at least work out the PS issues, but I dont know how to prevent any damage to the circuits with it disconnected from all the CRT grounds and anode.

Oh and that can on the power supply board (again I think its some kind of relay in a small round can was warm).

[DaveWM]

very 1st thing I checked is a RCA 142603 sand resistor, 100k, checked around seems like it should be a 3.9 ohm 10 watt (its not marked but I checked on line and with moyers and that seems to be it). Soooo I think I will check my stash and see what I have.

[DaveWM]

got a 3.9 7w, should be a 10w so I am just going to jump it in later and see if that does it, will get a proper larger wattage resistor later.

[DaveWM]

well that promply smoked, check the HOT, shorted, Not sure if it uses a bipolar transistor or the SCR in that model. This thing is not long for the curb...

[Gunslinger]

it's a regular transistor ECG238 will work. you have to remove the regulator board, jump the capacitor on the wing by the regulator board, put on isolation transformer with a variac and bring up slowly from 90 to 95 volts. You were going into shuit down mode. If the 3.9 ohm is gone, check the diodes on the input power. The start diodes are on the small board in the front of chassis.

[DaveWM]

Put a spare HOT in it, dinked around with it some more, replaced the 3.9 again. Its workign again but dont know for how long. leaving it play for a bit to see.

[ctc17]

ECG238 man that rings a bell...The 6JE6 of horz transistors.. That was the part that would break the set and send it to the curb when I was working on these sets in the 90s. That cost like $9 and lots of people would say trash the set when you told them there was a chance something else could be wrong that caused it to fail.

[Gunslinger]

you have to read the regulated B+ while it's running. Place the neg lead of the meter to Hot ground and positive lead on regulated B+

[DaveWM]

there were some test point on one of the boards,(the one in front of the defection board) 21v 27v and 11v

they were very close (+-.5v if i recall correctly). I will check again for exact numberrs and scope as well for ripple.

It ran for hours last night with not issue. I take it the startup is where the problem presents?