Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Recapped My Predicta Tandem, I don't know what to do
#63

So I'm home on quarantine and I decided to poke around in my set. I replaced all the resistors in the video amp and 3 had drifted up significantly, but it made no real difference. Then I noticed I'm not getting 400VDC on the 3CB6 video amp tube in the CRT shell. So first I checked the wire going into the .22 cap and only had 203VDC. According to the drawing I should have 400VDC going into the cap. Just to make sure I took the lead that goes from the cap to 3CB6 off and checked but the voltage going into the .22 cap didn't change. Next I noticed the blue wire that goes through the 120ohm resistor is supposed to have 250v on it. So I disconnected the 120Ohm resistor and checked it has 223v on it. Then I checked the other wire that feeds the .22 cap and it has no voltage on it. It would be the one marked at 1 on the drawing. I checked the 3300ohm, and 1500ohm resistors on the main chasis and board they test good. It looks like everything is fed by the N1 network which is brand new. How can I test it? By the way I'm using the philco drawings.


Attached Files Image(s)
   


Messages In This Thread
RE: Recapped My Predicta Tandem, I don't know what to do - by apERNA1985 - 01-28-2022, 11:12 PM



Users browsing this thread: 29 Guest(s)
[-]
Recent Posts
Help identifying
Welcome to the Phorum! With the cabinet being custom it makes it harder to be certain about the radio and phono model...klondike98 — 09:11 PM
Using a loop on a long wire 60B
There's also many DIY loop antenna options on YouTube your son may want to check out. Some are quite decorative and can ...RodB — 03:36 PM
Using a loop on a long wire 60B
It could be hit or miss getting a salvaged loop to resonate for the desired station and it will require some sort packag...Chas — 02:50 PM
Using a loop on a long wire 60B
I searched but couldn't find an exact answer.  I'm giving my son my 60B that I electrically restored some 8 years ago (I...JohnCT — 12:49 PM
38-10T chassis Restoration begins
Hello Mr Fixr, years ago I had to wash two vcrs one was used by the school disctrict and the other was a family who had...radiorich — 10:53 AM
38-10T chassis Restoration begins
My dad's manager took the NRI course many years ago and gave me his course booklets. One of the course lessons was on r...MrFixr55 — 10:20 AM
Philco 38-2 Low Volume
I have done the RF and magnetic tuning alignment. The magnetic tuning really does its job quite well. Had to do three tr...dconant — 08:41 AM
38-10T chassis Restoration begins
Hello Dan, Very cool !! morzh , I have seen people put computers and other items in the dish washer ! Sincerely Ri...radiorich — 11:26 PM
38-10T chassis Restoration begins
Arran I also washed tuning caps in dishwasher and in soap water without having removed the micas. Upon drying, it wa...morzh — 02:00 PM
38-10T chassis Restoration begins
Hi Richard, I used to build houses and we used a lot of those gold flake counter tops. We even used gold flake ceramic t...dconant — 11:11 AM

[-]
Who's Online
There are currently 2588 online users. [Complete List]
» 1 Member(s) | 2587 Guest(s)
Avatar

>