Recapped a CTC 7AH..still have a problem
 

:scratch2:got a '58 RCA CTC7AH color console"Grenoble"
completely replaced all of the E-caps;including a old Bumblebee on the A/C
safety interlock...047@600volts..on the variac on the first power up it shows a huge current draw:scratch2:on the Amp gauge..I then use my 3way Dim-bulb tester with all of the tubes pulled and the CRT unplugged also..bulb does'nt light...while on the variac brush starts to arc..i shut her down instantly.i tested the set on the Dim-bulb alone to test for a short in the Primary...no problem there...double checked all connections with the schematic to make sure i didn't mess up on that end...what gives:scratch2:

check resistance at the plug

I am assuming you are starting at zero with the variac, should be zero volts and zero amps.

should be about 3-4 ohms on the plug. with the power switch on.

if that checks then check resistance at B+ (right after the choke), should be around 10k AFTER the filter caps charge up from the voltage of the VOM, do this with the set unpluged of course. If the B+ resistance is a lot lower then you have a short somewhere or a filter cap installed backwards. If it uses a doubler cap in the power supply make sure you have it wired up with the correct polarity, check it to the schematic, doublers can be tricky.

ok with power sw on with no power of course..you stated that to test for 3 to 4 ohms @ the safety interlock..trace over to the filter choke.correct?@10K ohms

I trust nothing so I would check the actual plug for the 3-4 ohms.

so if that clears yes look for the filter choke I think there is a thermal breaker there.

again triple check those 160uf caps C1 should be a single section or a single cap the neg does NOT go to the chassis ground.

that's correct:thmbsp:..on the set having a thermal switch; one side goes to the single section 160uf@250 is on the positive side of the caps center leg; going too the thermal switch,and on to the filter choke..the negative is to the safety fuse holder,and one leg on thermal sw is going to the power switch:scratch2:the single cap is not grounded...this must be a simple fix..i hope i've not damaged this 53 year old set..it has a beautiful cabinet

you lost me on the power switch. it goes plug, saftey cap, on off switch, thermal switch (the heater part), primary of transformer.

was it working before the recap?

Dave
I installed a new 160uF@250 that's on a fiber wafer....the other 2 E-cans,2 and 3
were junk; i used 2 new terminal strips that were long in length mounted them
on the empty space rear of the tuner soldered all of my new radial E-caps
to the new strips making sure to only ground the one side that was required
too...place the leeds to each correct value one at a time..double checking as went according to the schematic:yes::scratch2: no the set
hasn't been on for over 35 years

pm sent

the color picture tube is mint:yes::thmbsp:; tested with my Sencore CR-161 tube tester

If you haven't replaced the papers/or paper-milars those can some times cause troubles in early roundys.

Here is my CTC-7 after I had replaced only electrolytics. Bad horizontal, lousy vertical, colors all hosed:

http://antiqueradio.org/art/RCACTC-7FirstImage.jpg

Here it is after I replaced the old "maroon drop" mylar caps:

http://antiqueradio.org/art/RCACTC-7Recapped.jpg

Still need to do the usual setup (convergence, etc.), but you get the basic idea.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Phil, can you pls confirm the resistance of the primary of the power transformer.

my 3-4 ohms is on a CTC-16