Rca 21D641 HV issue.
 

So I have replaced the filters to start off and that is all the work I have done so far just so I can get a baseline. With no yoke plugged in I pull about maybe 7 kv (I have a shorting bar in the socket so hv will come up.), but when i plug in the yoke and power up the set the hv droops to 100v with brightness at max and 2.8kv with brightness at minimum. I have a bad feeling my yoke may be bad. I ohmed out the yoke and the results were inconclusive. The vertical section reads normal, but when i measure the horizontal winding I get maybe 6.9k wit the target being 29 ohms(provided I am measuring the right pins). Not sure if my yoke may be bad or not. Here is a picture of the yoke from what I gather vertical winding is from pins 1 and 2 and the horizontal is from pins 8 and 4. Your thoughts?

oops. I posted in the wrong fourm. Wasn't paying attention when I wrote this up. Could someone move this to early B&W?

I think the ETF may have a new yoke for this set. Can anyone verify if my yoke may be bad before I buy the new one? From what I gathered, my yoke is bad.

Measure between pins 4 and 5 and then from pins 5 and 8. They both should read the same and about half of the total spec of 29 ohms.

Always use chassis numbers! Model numbers don't mean squat to us old timers.
I'll look up the model number in Riders. I might have a good used yoke. :thmbsp:

According to Riders, it's a KCS97 chassis. With a good CRT and a recap, it's an excellent performing set!
It's a 90 deg yoke, don't have one I can spare! Dave. :sigh:

5 and 8 read 9k and 4 and 5 read 700 ohms. Now I am pretty sure the yoke is bad.

I may have one. Got some. NOS stuff in a box, can anyone come up with a part number, Stancor, Merit, Triad?

Stancor DY-16A Merit MDF-92 Triad Y-41-1

If you can find one eric, I'll take it.

Y41 sounds familiar, I’ll check when I get home this evening.

Where are you reading the yoke resistance? On the octal plug or on the yoke terminals where the wires attach? Try reading on the yoke itself - the person soldering the octal socket might have been having a bad day.

Testing the yoke from the actual yoke terminals with the ring tester reveals it is BAD. I need a new yoke ASAP, this project has to be finished before November. Eric, if you have it consider it sold.

Before you assume your current yoke is beyond repair, how about trying to repair it first? I’ve seen yokes before that had some corrosion on the copper wires near where they join to the solder lugs, and a cold solder joint isn’t outside the realm of possibility either. Poke around, not like you have anything to lose at this point.

The windings that fit on the tube neck have an area of corrosion and I believe i see a broken wire and almost all the varnish on those windings are gone so its shorting too. Its dead.

Okay, I found one, a Triad Y-41 (no -1 suffix) assuming it's in the right box (check pictures) it's a 90 deg yoke, 24 Ohm horiz 39 Ohm Vert.

It looks new although some of the soldering on the inside looks a little rough, possibly someone installed the Network components since they seem to be there. There is a small chip in the Bakelite that won't affect anything, there is no cover because they never came with one.

It's yours for shipping.

Due to my work schedule I won't be able to ship until Thursday.