My 630

[Geist]

Hi All;
Yea, I wish I could do everything at once, I try to plan ahead and get what I think I need in the next couple of week or month or two.. I have plans for some test equipment that I need from one of the members, I also am hoping to do some trading for some Tubes that I need, and I need the Paper Caps.. Just can't do all of that at once.. I can only do so much each month.. I did get that 8TS30 for shipping, but that was money I had planned on for other things.. So, everything takes time for me..
THANK YOU Marty

[Phil Nelson]

I know it's hard to be patient, but I would set this TV aside until you can replace the paper caps. It is a losing game to chase individual problems when the TV still contains dozens of defective capacitors. You don't want to burn up any more stuff.

Just my $0.02.

Phil Nelson

[bandersen]

Originally Posted by Geist

Hi All;
No, I had always said electrolytics, couldn't aford to do both at the same time.. That is the next thing to do, I need to make a list of what I need and find them.. Not sure if Mouser or Digikey or Allied.. Will need to compare prices.. Does anyone have any suggestions as to who has the bast quality and prices ??
THANK YOU Marty

Those three vendors are fine in general, but have a limited selection of axial film capacitors and they are on the expensive side. Just Radios is a popular choice for inexpensive axial caps.

Here's a quick check I did for Axial 0.047 @ 630v (one of the most used values)

Just Radio - $0.46
Allied - $0.48
Mouser - $0.79
Digi-Key - $2.02

That's assuming you want to use axial and not something like radial Sprague orange drops.

[Geist]

Hi All;
Thank You Bob, that is the kind of information that I need..
I need to go thru the parts list and find the different values and how many I need.. I figure it would be easier and cheaper with shipping, to get them all at once.. Yea, I could get a dozen .05's or .047's, and get them here quite soon.. But, I would need all the rest.. On the other hand, getting small batches, would mean getting some each week or so.. I will look at what is needed then decide..
THANK YOU Marty

[old_coot88]

Marty,
Just a little tip on paper caps and the criticality of leakage. The most critical is a grid coupling cap feeding G1 of a power stage from the plate of a preceding stage. Because the plate is positive, any leakage of DC thru the cap will drive the power tube's grid more positive, causing the tube to overconduct. Since power tubes already run hot, thay have little 'headroom' for overcurrent.

In your set, the most critical coupling caps (in descending order) would be C178, feeding the grid of the 6BG6.

C157, feeding the grid of the vert output

C208, feeding the grid of the audio output

then the four caps in the video chain mentioned earlier

then any bypass caps along a B+ line or on a tube's screen grid (G2). And any bypass caps along the AGC (or 'picture control') line.

lastly, any bypass caps having a low resistance in parallel, such as a cathode bypass.

So if you elect to replace caps in batches, that's a general guideline that'd apply to other sets as well.

[Geist]

Hi All;
Thank You, Old Coot !! I am about to make a first list and this is Just what I needed to know.. That way I can continue on.. I think for now, I will skip the RF and IF sections, and concentrate on the rest.. Thank you for the guidelines, this alone makes the posting all worth it..
THANK YOU Marty

[old_coot88]

Originally Posted by Geist

...I am about to make a first list and this is Just what I needed to know.. That way I can continue on.. I think for now, I will skip the RF and IF sections, and concentrate on the rest..

Even if you elect to do those last, it probably wouldn't hurt to clip an end of each one loose temporarily and check it for leakage. That'd give you a gauge of their overall condition, and also catch any on the B+ line or AGC* line with serious leakage.

*Actually, "AGC" (for automatic gain control) is a bit of a misnomer in this instance, because gain control is not automatic at all but purely manual via the 'picture' control. It requires you to adjust gain with varying signal strength. It's just part of the charm of these old sets, like riding the gain on an old TRF radio.

[Geist]

Hi All;
Old Coot, I have an old Capacitor checker made by Solar, but it hasn't had its caps checked or changed, nor has it had its tubes checked.. So, IF this Cap checker, is not functional at present, Is there another way to check for Leakage ??
I have decided to make a list of everything and see what the prices are, and then IF I need to I can par down..
Bob Andersen, When you got Caps for your 630, What did you use for your Mica caps ?? Was it Mica or something newer ??
I also assume that just a number is a Mica cap in Picofarads, am I correct ?? Like 1200..
THANK YOU Marty

[bandersen]

I didn't get mica caps, just replacements for the paper. Mica caps are far more reliable than paper. I think Ive only replaced three or four so far in TVs. I'll check them only if I have problems after replacing all the other caps.

[old_coot88]

Originally Posted by Geist

...I have an old Capacitor checker made by Solar, but it hasn't had its caps checked or changed, nor has it had its tubes checked.. So, IF this Cap checker, is not functional at present, Is there another way to check for Leakage ??

You can use a multimeter, VTVM, or VOM on the high ohms scale. It won't test for capacitance value or breakdown voltage, but is a quickie method of checking for leakage.

In grid coupling caps and in bypass applications you want to see infinite resistance, but in cathode bypass applications where there's a low resistance in parallel with the cap, a little leakage wouldn't hurt anything.

[Geist]

Hi All;
Thank You both, that Helps alot, By not getting Mica's, it cuts down on what I need to get..
THANK YOU Marty

[Geist]

Hi All;
I just placed an order with Mouser for the most popular sizes that they had.. The rest I will get from Justradios, (Mostly Orange drops) they are closed for now, so it will be about a week or two before I place an order with them to get the rest of what I need..
What they aren't here yet !! I guess, I'LL have to wait for them to arrive..
THANK YOU Marty

[bandersen]

Before you place that order keep in mind that Just Radios doesn't have Sprague "orange drops", they have "orange dips". Not the same thing at all Also, those "dips" are radial and not so easy to use as the long lead length "Tubular Axials".

Here's a picture from left to right - Sprague orange drop, orange dip, generic yellow poly axial and the more expensive name brand (Mallory) caps Mouser sells.

[old_coot88]

Still curious as to whut shorted and took out those two resistors.

[Geist]

Hi All;
Bob, I'm a little confused then.. What and where did you get the caps needed for the 630 ?? Most of the caps I ordered from Mouser were only the more popular variants.. How and who do I get what is really called for in the 630 ??
From what I see, I need .1, .01, .015, .025, .035, .05, .002, .0025 .004, .005, and 6500, 1500, 1200, 1000, 680, 470, 390, 270, 82, 75, 56, 51, 47, 43, 33, 10..
I got .047, .01, .024, .02, .0039, 1500pf, 1200pf, 1000pf and I am not even sure they were the correct ones..
THANK YOU Marty