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timmy 10-18-2022 12:56 PM

It starts at 5k and slowly rises to 6.30k

Yamamaya42 10-18-2022 01:07 PM

Quote:

Originally Posted by timmy (Post 3245672)
I’m getting a really bad reading on pin 8 of v1 should be 3200ohms 3.2k I’m getting 6.30k I figured I would check resistance on v1 and v2

You are aware of the note “measured from the output of X2” that would be the cathode of the diode, before L54, and not ground, if this is what you are doing, then it's a good sign the power resistors are bad, but if you are measuring from ground, your readings are wrong.

timmy 10-18-2022 01:08 PM

The reading starts at 5k and rises slowly to 6.30k while it should be 3200ohms 3.2k

timmy 10-18-2022 01:10 PM

No I’m not measuring from ground I’m on the second diode which would be x2 output

Yamamaya42 10-18-2022 01:23 PM

Quote:

Originally Posted by timmy (Post 3245676)
No I’m not measuring from ground I’m on the second diode which would be x2 output

Then, that seems to point right at the power resistor networks I pointed this morning, replace all the 2-3 watts in the area, and the power diodes, cost from mouser, 10-15$

timmy 10-18-2022 01:27 PM

I’ll post the other resistance readings from v2 v3 because they are way off

Yamamaya42 10-18-2022 01:47 PM

As it has been mentioned before, by myself and others, your best hope to get this working is not to touch any capacitors in the area what so ever, and VERY CAREFULLY replace all resistors with 2% or better carbon film types, paying close attention to placement and lead dress, IE, try to make it look as close to the original as you can, and since technology has changed so much over the years and they have gotten smaller, it never hurts to go up one size in power rating, cause even if you do, what you are putting in will be physically smaller than what you take out, they are that much more efficient than the old ones.

timmy 10-18-2022 01:48 PM

Ok v2 and v3 are within good range only v1 is a problem
The only pin that’s not right is pin 8 should be be 3.2 but it’s measuring 6.30

Yamamaya42 10-18-2022 02:01 PM

R39,R40,R41 obviously, get all 3 in 3w, but I would not stop there, you should have R48,R49,R50 on hand as well in case. It would not hurt to change R22 as well.

jr_tech 10-18-2022 02:18 PM

Quote:

Originally Posted by timmy (Post 3245672)
I’m getting a really bad reading on pin 8 of v1 should be 3200ohms 3.2k I’m getting 6.30k I figured I would check resistance on v1 and v2

Did you measure from output x2, like it says in the note? :scratch2:


Edit
Never mind, I responded to an older post,I missed a page!

jr

Yamamaya42 10-18-2022 02:20 PM

Quote:

Originally Posted by jr_tech (Post 3245682)
Did you measure from output x2, like it says in the note? :scratch2:

jr

I already asked him about that. :D

timmy 10-18-2022 02:21 PM

R22 is a trap

Yamamaya42 10-18-2022 02:26 PM

Quote:

Originally Posted by timmy (Post 3245684)
R22 is a trap

my error, that's R38, I jotted down the "22" next to the right number! :P

timmy 10-18-2022 02:39 PM

I will tell you I have the chassis out on the bench but this circuit should do what it has to on the bench and I put an antenna input and the voltage goes up very little so it’s resistor time I doubt it would have made any difference it it were in the set at this point

timmy 10-18-2022 05:25 PM

Ordered the resistors but I’m wondering where the 7 volts is coming from on v1 pin 2 it’s almost like the tube is locked on there for pulling the voltage down on pin 8 where on this tube is there something that would make it conduct or turn on full or partial.


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