Quote:
Originally Posted by old_tv_nut
I just acquired a CTC-5  ... First order of business will be a recap - if anyone has already created a list of required caps, I'd appreciate it, otherwise that's the first step for me. |
Congratulations for this nice peace of American television history.
For me the first step is an inspection of the chassis and the crt. Check for previous repairs. Check for the correct tubes in their places. Check for burned caps, coils, resistors etc..
My philosophy of recapping is to replace only those caps which are absolutely necessary for proper working condition. I want to leave the set in nearly original condition as it is possible. I know that many people replace all caps whether it is neccesary or not. But this is not an intelligent choice. Many caps are not critical.
Note for designations: I have the RCA field data service sheet.
Next step: reforming electrolytic caps C103,104,105, see:
http://www.vcomp.co.uk/tech_tips/ref...eform_caps.htm
I use a mains power supply with 0 to 350 volts in steps of 5 volts and measuring the current. Step by step with increasing voltage. Do not exceed 80 mA current in low voltages and 40 mA with high voltages.
Candidates for recapping: all coupling capacitors and waxies excluding micas and ceramics. Look for R C parallel, they are not critical. Screen grid caps are also not critical. Caps with a low voltage difference are also not critical. Those caps with a ! are a must. I recommend to check all caps with a ! first and then fire up the set and see what happens. While fire up, remove F102 and measure the d.c. current. This should not exceed 600 mA!
Power supply: C133 !,
PW600 (line oscillator): check C601, 602, 603.
Horizontal output and high voltage: C112, 115, 119, 120.
PW500 (vertikal osc. and output): C501, 504 !, 507 !, 508 !, 509, 510 !,
PW700 (color and video output): C714 !, 715, 731 !, 732.
PW400-A (video amp): C403, 132A, 132B.
PW400-B (blanker): C408 !
PW300 (I-F): nothing
PW200 (sound): C212 !
PW200-B (AGC, sync): C217 !, 222 !
Tuner: C116 !
Resistors: I found some resistors with increased resistance. But checking these is recommended when you have a raster or a picture.
Kind regards,
Eckhard