Still working on my Sylvania - Page 2 - Videokarma.org TV - Video

jeyurkon · #16 09-23-2009, 12:49 AM

I tried to find the old HV cap I replaced, but I guess I threw it away because it was leaking oil. I wanted to post a photo for you.

It looks just like any other bumblebee except that it's much larger.

I wonder how many sets used these in the HV section. I haven't worked on that many sets, but the other models I've seen used either doorknobs or plain paper for HV.

John

Mick AV-8 · #17 09-23-2009, 07:13 AM

Thanks for looking John!!
Have not received by cap order yet from Radio Daze.
But when I start to dig I know I will have an additional list or order to place and so I will wait to oreder these two caps for the HV section. So to be clear..these are two dog bone paper caps located in the ceramic cage? right?
Also does anyone know of the other two high voltage caps that are in this set that need replacement?

jeyurkon · #18 09-23-2009, 10:56 AM

Quote:

Originally Posted by Mick AV-8

Thanks for looking John!!
Have not received by cap order yet from Radio Daze.
But when I start to dig I know I will have an additional list or order to place and so I will wait to oreder these two caps for the HV section. So to be clear..these are two dog bone paper caps located in the ceramic cage? right?
Also does anyone know of the other two high voltage caps that are in this set that need replacement?

Could you take a photo of the dog bone paper caps you're referring to? I'm a bit confused.

When you ask about the other two, are you asking about finding a supplier for them, or if there are two more that you need to replace?

John

***Eric H*** · #19 09-23-2009, 12:39 PM

Caps of that voltage are usually Ceramic, are you sure they're bad?

I have (somewhere) some ceramic .001@10,000 they worked good in Horiz section of the Motorola VT-71 sets, I could probably dig them up if you need them.

jeyurkon · #20 09-23-2009, 01:37 PM

Quote:

Originally Posted by Eric H

Caps of that voltage are usually Ceramic, are you sure they're bad?

I have (somewhere) some ceramic .001@10,000 they worked good in Horiz section of the Motorola VT-71 sets, I could probably dig them up if you need them.

Sylvania used oil filled paper caps. The one in my set was actually a bumblebee and it has the same part number as in his set so I assumed it would be the same. The part list for his set also refers to it as a molded paper capacitor.

I used the 15KV 470pF film cap from justradios because it was about the same physical size and was easy to replace.

John

jeyurkon · #21 09-23-2009, 02:40 PM

I'll send you a different scan tomorrow that has the complete part list. I think I sent you Wallace's which only gives a partial list.

John

Mick AV-8 · #22 09-23-2009, 08:40 PM

Sorry John..beginers do not know all of the language...
I will just go back a little..what I ment by ceramic was in the HV section pictured. Are the two paper capacitors inside this(as you can see white ceramic block) cage?
And before I was asking about the other two paper caps you mentioned in your previuos response about another two 0.0005/10KV caps located elsewhere in the chassis. I was wondering if anyone knew where they were?
Here is also a picture of one of the three paper rolls that needed to be restuffed.
I was wondering if it was easier to solder under the chassis?
And I was looking for some pictures of how other did this chore?
Thanks fao all your patience and time in responding!!

bandersen · #23 09-23-2009, 09:27 PM

Quote:

Originally Posted by Mick AV-8

...
Here is also a picture of one of the three paper rolls that needed to be restuffed.
I was wondering if it was easier to solder under the chassis?
And I was looking for some pictures of how other did this chore?
Thanks fao all your patience and time in responding!!

Yes, it's definitely easier to solder them under the chassis. That's how I was doing it until recently when I saw others re-stuffing them. I asked some questions, bought some tools and practiced on a few old caps I had lying around. Now that I've got the hang of it, I'll never go back

The cardboard cover ones you've got are easier than the bare metal ones because you can hide the cut you'll be making. Here's my current technique:

1. Make careful notes of the capacitor wiring then remove it from the chassis.

2. Remove the cardboard tube. If it's stuck on tight, I heat it up using a heat gun or bake it in the oven on low heat for a few minutes.

3. Once it's off, clean the goop off the can with lacquer or paint thinner.

4. Cut the can open near the base with a dremel tool and cutoff wheel.

5. Carefully pull the can open using some heat if necessary.

6. Unroll the old capacitor foil to expose the electrodes and clip them off near the base.

7. Drill a tiny hole near each terminal and one more for the ground near the outer edge.

8. Arrange the new caps so they'll fit inside then can and solder them in.

9. Remount the capacitor and get the set working.

10. Finally, glue the can back on with a little epoxy and slip the cardboard tube back over.

Yeah, it's a lot of work!

I've got some to do in a few days. Maybe I'll record a video if you're interested.

Bob

jeyurkon · #24 09-23-2009, 09:28 PM

Quote:

Originally Posted by Mick AV-8

Sorry John..beginers do not know all of the language...
I will just go back a little..what I ment by ceramic was in the HV section pictured. Are the two paper capacitors inside this(as you can see white ceramic block) cage?
And before I was asking about the other two paper caps you mentioned in your previuos response about another two 0.0005/10KV caps located elsewhere in the chassis. I was wondering if anyone knew where they were?
Here is also a picture of one of the three paper rolls that needed to be restuffed.
I was wondering if it was easier to solder under the chassis?
And I was looking for some pictures of how other did this chore?
Thanks fao all your patience and time in responding!!

That's called the High Voltage Scanning Assembly. In the second photo the side that you are looking has the terminals and is has a bakelite cover. Under that are a couple of resistors and the two 5642 HV Rectifier tubes. On the other side of the ceramic inside the cage are the two 0.0005uF 10KV capacitors. You have to remove the cage to get at them. The SAMS probably tells you how to do that. Otherwise you'll have to look at it and figure out how to remove it. I don't have this particular set so I'm limited in the advice I can give. It appears that it is held on by tabs in two slots. You may just need to spread the cage out past the tabs and slide it off.

This is an area that may hold charge for quite some time and can be dangerous. I doubt that the original caps can hold charge for long though. If you discharge the CRT anode lead you'll probably be o.k.

I've forgotten what I actually did send to you. Could you tell the the page numbers that are in the pdf file? That'll let me know if I sent everything and if I used the factory service book or the Wallace's.

These are the only two 10KV capacitors in your set.

John

jeyurkon · #25 09-24-2009, 10:13 AM

I've emailed you a complete part list and a better document this time. It's from the factory service manual. Sorry about the incomplete list. It must have made ordering caps difficult.

John

Mick AV-8 · #26 09-24-2009, 01:35 PM

Thanks guys for your help.
Bob if you can post some pictures of how you stuff the cans..it will be very interesting for all to see. The paper tubes seem to be riveted on to the metal chassis.Guess you need to dremel them off or drill them out.

bandersen · #27 09-24-2009, 06:48 PM

Take a close look - those might be mounting plates for the capacitors that are riveted on. The capacitors are usual attached via four metal lugs that are twisted through slots. Like these.

Check out zenithfan1's thread here for a tutorial.

I've got some photos here.

Maybe I'll make a more detailed step-by-step with my next project.

jeyurkon · #28 09-25-2009, 09:20 AM

I thought this might be useful to others.

John

Mick AV-8 · #29 09-29-2009, 08:14 PM

Finally recieved my caps from radio days..they looked at the schematics and sent me a total of 33 caps. And 13 of them are electrolytics. Thought there would be more than 33 of them..does that sound right?
Still trying to figure out how to stuff the paper cans.
I have to do three of them C1,C2 and C3.
Looking at the chart for say C1 ..I have to put in a 40mf/350v ( have a 47mf/450v) also an 80mf/350 (have a 100mf/450v) inside the can.
But I must be blind..well I am using two diff pairs of glasses now..but I can not find the C1 item on the schemeatics. Can someone help me figure out how to attack this problem?
Here is the underside two together are C1 and C2 , the one alone is the C3 on the schematic. Those tangs you twist to hol it in place..those are ground right?

***Eric H*** · #30 09-29-2009, 09:01 PM

According to your schematic 156 and 157 are in one can, that would be the two section one shown on the right side of your first picture, those are 40 & 80 MFD @ 350v
You can use a 450 volt capacitor in place of a 350 but they are bigger and that can cause a problem when you are restuffing.

Right next to the lugs on the bottom is a logo, a half circle for the 40 and a triangle for the 80, you can see those on the schematic, also the values should be stamped in the paper sleeve of the capacitor.

The twisted lugs are the ground (negative) for the capacitor, however in that case the Cap ground is not the same as the chassis ground, that's why they are mounted in a Phenolic washer, matters not as long as you connect the - terminal of your new cap to the ground lug and the + to the lugs in the center.