Zenith 10S690 Volume Control Issues

[old_coot88]

Just need to verify solid continuity (zero ohms) as indicated by the red lines in the shetch:

[vortalexfan]

Originally Posted by old_coot88

Just need to verify solid continuity (zero ohms) as indicated by the red lines in the shetch:

Well if you mean using the continuity test to see if it beeps when the test leads touch the connection, then no there isn't any continuity. I traced back to the B- source which was the filter can negative, and I get continuity up until where C13 attaches to R13 after that I don't get a beep from my continuity checker until I get to one side of C11 which gives me continuity between it and the upper Volume control lug.
Which I'm assuming is what you wanted to know.

[old_coot88]

Originally Posted by vortalexfan

... I don't get a beep...until I get to one side of C11 which gives me continuity between it and the upper Volume control lug.

OK good. Now put the checker from the other side of the cap to where the signal lead exits the can. If it's got crumbly insulation, it should be easy to make contact. Or use a pin to stick thru the insulation. The checker should show continuity.

If it does, this suggests C11 is bad. Try the paralleled .0033/.0047 caps for C11.

[vortalexfan]

Originally Posted by old_coot88

OK good. Now put the checker from the other side of the cap to where the signal lead exits the can. If it's got crumbly insulation, it should be easy to make contact. Or use a pin to stick thru the insulation. The checker should show continuity.

If it does, this suggests C11 is bad. Try the paralleled .0033/.0047 caps for C11.

Well I didn't get continuity at that point that you told me to check, so I guess that means the capacitor is fine?
I'll still try the .0033 and the .0047 together to see what happens there,
also I'm trying to replace the old crumbling wire coming out of the IF can with some new wire.

I also have a question about how to go about putting that small cardboard spacer back into place on the bottom of the IF coil that helps keep the IF coil centered in the IF can, because it came loose at some point in its life and when I took the can apart it fell out and it looked like it was held into place with a dollop of wax of the same varity that they used to insulate the rest of the IF coil with, is that just everyday parafin wax or did they have something added to it to make sure it didn't harden right away so that they could brush it on to the bottom of the IF can spacer?

I would like to put that spacer back on and make it look as original as possible seeing as this is such a low hours set and is such a perfect candidate for restoration.

[old_coot88]

Hey, since this is a phono/radio rig, have you cleaned the phono/radio switch with Deoxit or similar? Jeez, I shoulda thought of that before. Senior moment.

[vortalexfan]

Originally Posted by old_coot88

Hey, since this is a phono/radio rig, have you cleaned the phono/radio switch with Deoxit or similar? Jeez, I shoulda thought of that before. Senior moment.

No, I haven't, I thought about it but haven't yet, but maybe, I should of tried that first.

I still am going to fix the wire for the IF can because it had crumbling wire insulation to the point that it had exposed wire.

[old_coot88]

Now that you've isolated which side of C11 the break is at, it's 99% gotta be in the switch.

On that cardboard spacer thingy, maybe a dab of 5 minute epoxy(?).