Still working on my Sylvania

[bandersen]

Not sure about C1, C2 or C3. I see C155 - C158 on John's schematic. Looks like 155-157 are in one can and C158 is on it's own.

The tangs are the common lead for the capacitor not necessarily ground. According to John's schematic they are connected to the -135V bus. That's why those caps are mounted on insulating wafers rather than directly to the chassis.

I think you'd have an easier time leaving the old caps in place and leave the leads going to the tangs. Clip the wires going to the + lugs for each cap section and solder them to you new caps. Solder the negative leads of the new caps to the old tangs.

At least until the set is working - then maybe go back and re-stuff them if you want to.

[Eric H]

It's also a lot easier to just look at what's marked on the cans and go with that rather than trying to figure out what goes where from the schematic, this also eliminates any errors from misprints.

[jeyurkon]

Eric, the part locations you gave are correct for the schematics I gave him. However, I think he also has a Sams, in which case they're labeled C1..C3 on the Sams. I'm not sure which one he is looking at.

If he looks at the one that I posted then your explanation should work for him.

Mick, 33 caps is about right. If they gave you one for C196, on the schematic I gave you, I'd leave it alone. It's polystyrene and should be o.k. If you replace it you'll have to readjust the horizontal frequency and phase.

John

[jeyurkon]

Originally Posted by bandersen

Not sure about C1, C2 or C3. I see C155 - C158 on John's schematic. Looks like 155-157 are in one can and C158 is on it's own.

The tangs are the common lead for the capacitor not necessarily ground. According to John's schematic they are connected to the -135V bus. That's why those caps are mounted on insulating wafers rather than directly to the chassis.

I think you'd have an easier time leaving the old caps in place and leave the leads going to the tangs. Clip the wires going to the + lugs for each cap section and solder them to you new caps. Solder the negative leads of the new caps to the old tangs.

At least until the set is working - then maybe go back and re-stuff them if you want to.

C158 is in the same can as C178, C210, C181. How's that for confusing. Sylvania never seemed to like C1A,B,C,D You need to look at the part list to figure out which ones are in which can.

John

[bandersen]

Thanks John - that is confusing!

[Mick AV-8]

sorry gents..I was looking at the SAMS and going back and forth..any was confused.
I will have another look tomorrow as it is late. Appreciate all your help..and I am taking your advice (John)on the C196..have that sucker highlighted in yellow.
many thanks on that!

[Mick AV-8]

Well I went a replaced the the .015mF in the horizontal tuner by accident.
C196 was not on the SAMS..so I goofed again.
This looked just like the rest of the waxy caps as I was going along.
The next day I relized what I had done..so I soldered the old cap back in.
Do you think that since I cut it out and put it back that I will still have to readjust all of the issues that John mentioned?
If so.. should I just put the new one back??
I was not thinking and had a different thought in my mind as to what the polystyrene cap would look like.
Not sure how to make these HF & phase adjustements if they arise..so I bet I will be posting that question in the future..if the sucker actually lights up.

[jeyurkon]

Originally Posted by Mick AV-8

Well I went a replaced the the .015mF in the horizontal tuner by accident.
C196 was not on the SAMS..so I goofed again.
This looked just like the rest of the waxy caps as I was going along.
The next day I relized what I had done..so I soldered the old cap back in.
Do you think that since I cut it out and put it back that I will still have to readjust all of the issues that John mentioned?
If so.. should I just put the new one back??
I was not thinking and had a different thought in my mind as to what the polystyrene cap would look like.
Not sure how to make these HF & phase adjustements if they arise..so I bet I will be posting that question in the future..if the sucker actually lights up.

It probably won't matter. You may have to do a slight readjustment of the horizontal frequency at most. It's just that the replacement could be much different than the original polystyrene in value.

John

[Mick AV-8]

Hi John,
Do you mean that it wont matter in the fact that I cut out and put back in the old wax cap?
Or I wont matter ..if I replace the old with the new cap?

Is the HF adjustment the little screw comming out of the back of the chassis?

[jeyurkon]

Originally Posted by Mick AV-8

Hi John,
Do you mean that it wont matter in the fact that I cut out and put back in the old wax cap?
Or I wont matter ..if I replace the old with the new cap?

Is the HF adjustment the little screw comming out of the back of the chassis?

I meant that it won't matter that you took the old cap out and put it back in. I'm reluctant to refer to it as "old wax cap" because that sounds like paper to people when this one is polystyrene.

Yes, it's next to the size switch. That's the top core which is labeled horizontal hold on the diagram, and the bottom core is on the inside and that's the phasing.

When you get to the point where you need to touch up the horizontal hold you want to remove the 6AL5 discriminator tube and adjust the hold until the picture is nearly normal and moves slowly across the screen. Then when you replace the 6AL5 it should lock in and be stable as soon as the tube warms up. That 6AL5 has a 4.5 ohm resistor in series with it's heater. It may be bad or at least increased in value. You should probably check it. It's meant to keep the 6AL5 from heating up as quickly as the other tubes and gives the horizontal a chance to get close to the proper frequency. Otherwise it could lock in on a harmonic. Not likely, but possible.

John

[Mick AV-8]

Thanks for making that clear to me..I get my mords wixed very easily.
I can see you are reluctant to call the polystyrene cap ...a wax capacitor..but this sucker C196 looked just like the waxed paper ones ....as I was cutting them out.
It was not in a plastic encasement ..but a roll covered in wax.
I guess the roll inside has the polystyrene (PS) material that has better dielectrics or something.

[jeyurkon]

Originally Posted by Mick AV-8

Thanks for making that clear to me..I get my mords wixed very easily.
I can see you are reluctant to call the polystyrene cap ...a wax capacitor..but this sucker C196 looked just like the waxed paper ones ....as I was cutting them out.
It was not in a plastic encasement ..but a roll covered in wax.
I guess the roll inside has the polystyrene (PS) material that has better dielectrics or something.

That's correct. It looks just like any other paper capacitor, but it's not.

John

[Mick AV-8]

Exactly..here is the cap covered in wax like the rest.. looks the same.
I am also amazed at how small the new electrolytics can be when you compare them against some of the old ones being replaced. The new ones could be five times smaller.
Still plugging away..until next bump in the road.

thanks again.

[jeyurkon]

I found the HV cap that is the same as what they used in your set, according to the parts list. I'm attaching a photograph of it. I had called it a bumblebee. Maybe that's not quite the correct term since it didn't have stripes for a color code.

You probably have a few Micamold capacitors too. Many of mine were bad even though they were truly mica. The Aerovox ones were o.k.

I just noticed that C215, in the Sylvania schematic, is listed as either a 0.00075uF-1,000V-Mica or a 0.00075uF-1,600V-Paper capacitor. You should probably check to see which you have. If it's paper, you probably need to replace it. Because of the way it was listed, they may or may not have sent you a film cap to replace it with.

John

[Mick AV-8]

Looks like I have a mica (pictured) in this spot. Though it looks a little beat and that it may have gotten quite hot...
I do have quite a few of these plastic bummble bees..and though they are plastic cased..I am asuming they are still paper inside and will be trying to replace them.

Here is a mystery orange cap in the center section. I do not see it on the list...does anyone know what it is for???

Thanks