Ts18 verticle problem

[Zenith26kc20]

Have you checked the value of the vertical controls? I had a open vertical centering on a TS-18 that drove me nuts! It had sweep, just bizarre. I had another one with 1/2 the value on vertical centering control. I had to add resistors on each end. Once I did, it worked great.

[timmy]

Originally Posted by Zenith26kc20

Have you checked the value of the vertical controls? I had a open vertical centering on a TS-18 that drove me nuts! It had sweep, just bizarre. I had another one with 1/2 the value on vertical centering control. I had to add resistors on each end. Once I did, it worked great.

Both the vert hold and the size are good, ohms wise and the vert centering works correctly. This set is bizarre since I cannot find anything wrong.

[jr_tech]

Do you still have the mis-matched capacitors in the vertical output?
Are you absolutely positive the vertical circuits are wired correctly?

Do you have a spare vertical oscillator transformer?

jr

[timmy]

Originally Posted by jr_tech

Do you still have the mis-matched capacitors in the vertical output?
Are you absolutely positive the vertical circuits are wired correctly?

Do you have a spare vertical oscillator transformer?

jr

I still have the different caps in place but they both test what they should in NF 4.50NF and I went over the SAMs and more then double check everything. Which is the vert oscillator trans T? I may have one from another set. I don't think there is a vert oscillator trans in the ts18.

[jr_tech]

You are correct... no VOT in the set... sorry !

jr

[bandersen]

Is one of the caps in the vertical ceramic ? It's capacitance will change when high voltage is applied causing problems. That's why you should use film or a ceramic cap much larger than what is called for. Swap the two caps around and see if the problem changes.

[timmy]

Originally Posted by bandersen

Is one of the caps in the vertical ceramic ? It's capacitance will change when high voltage is applied causing problems. That's why you should use film or a ceramic cap much larger than what is called for. Swap the two caps around and see if the problem changes.

I thought about switching them around. I did put several red film caps in series and parallel to make .005 but that didn't do anything to help. I have the one white tubular on one side and 2 ceramic 2kv caps on the other side and are equal to the NF of the other but if the capacitance changes with hv then I guess it won't work.

[jr_tech]

2kV??? those caps should be at least 6kV!

jr

[timmy]

Originally Posted by jr_tech

2kV??? those caps should be at least 6kV!

jr

I know 6 kv but I'll post a pic of the screen the way it is and another pic with a .01 cap paralleled with the .004 . This is baffling since it has a bright screen and a decent pic with these caps, which is only one side of the verticle has the ceramic.

[timmy]

Ok here's the pics with the ca and without. And I tried another .004 I made up of film caps, 2 to match the pf. Ok the next post has the other pic.

[timmy]

And the other.

[EdKozk2]

Timmy,
Where did you ground the .004 cap, chassis or B- buss. It should be the B- buss.
Ed

[timmy]

Originally Posted by EdKozk2

Timmy,
Where did you ground the .004 cap, chassis or B- buss. It should be the B- buss.
Ed

It's grounded to a factory tie strip that's tied to the 6sl7 that's where the .004 is grounded. Nothing was changed was all original where the cap was is where the new one went. The weird thing is upon turning it on for the first time it had a pic that rolled but the hold pot had to be maxed at one end to stop the roll then it went down hill fast to what I have now and it was good with those caps I have in there now . It's on b- not the steel chassis.

[timmy]

Ok there is no more ceramics in the verticle and still after putting together several 2 kv metalized caps in series to make 6kv and the proper NF for this application no change. Is it possible that the 2 ceramics in the horizontal could be causing this even though the horiz works perfect. The ceramics in the horiz are .002 10 kv. My mistake the caps in the horiz are .002 not .001 so I don't think that would make much difference.

[compucat]

You need the correct 6kV tubular caps in the vertical circuit to have correct linearity. The mix and match does not work well here.