24NC31 Zenith, give me your thoughts...

[roundscreen]

Please double check that paper can. if it was mounted on the chassis like the one you see in the picture it is isolated from the chassis ground.
When you install the new cap , Make sure it is wired in the same way as the old one and not touching the chassis ground.

[bgadow]

As others have said, put the caps in parallel and there will be no problems. 160 was a popular value; with some hunting you can find both a 100mfd & a 68mfd. which will work nicely. Space can be tight under the chassis, especially if you are replacing all the electrolytics; you might have to get a little creative. You could also mount them on a terminal strip above the chassis if you had to but that isn't as pretty.

I have some spare belfuses if you want to go that way.

[Carmine]

I am having trouble finding the capacitors I need for this Zenith set. Here are the sizes I need to replace the "cans". There was only one paper capacitor in the set (vert) and I've already done that one.


(1) 200mfd 25v
(2) 160mfd 250v
(1) 100mfd 475v
(1) 80mfd 475v
(2) 50mfd 475v
(1) 40mfd 25v
(2) 4mfd 475v

The problem seems to be the 475v rating. I find plenty with a 450v rating, but nothing higher... At least at my local radio shop and on Moyers.

Where should I buy them?

[jpdylon]

Check out justradios.com They have 500v caps in those values. Great place to get caps. You can use the "shopping cart" feature if you don't want to e-mail them an order form.

[Carmine]

Justradios.com has only 10, 20 and 40mfd sizes in the 500v section. I'm just going to have to put a bunch of these in parallel aren't I?

What about my two 4mfd 475v? Put four 1mfd orange drops together?

[Adam]

I had the same problem in this thread: http://www.audiokarma.org/forums/showthread.php?t=89849 I still haven't decided what to do, and I was just trying to sort out all the references I got in that thread this afternoon. From the different places suggested to me in that thread, this is what I found: 100mfd-500v snap ons at http://www.alliedelec.com/Search/Sea...6787804769617F. But snap ons never look very good mounted on terminal strips under the chassis, so I'm thinking about replacing 2 of the original cans with those JJ multi-section caps mentioned earlier in the thread: one 50/50 - 500v and one 100/100 - 500v (also using one of the 100s for the 80, and one of the 50s for a 50-450v), they're at www.tubesandmore.com (to find them, they're under multi-section caps - not electrolytics). It won't look totally original, but it might look better than the snap-ons. As far as the 160mfd-250v, www.mouser.com has them (160-350v) but they're 12 bucks a piece. As far as the 4mfd-475 nobody seems to have them, I might just try replacing them with 10mfd and see what happens. I haven't actually ordered from any of these places or tried any of these yet though. I have 15 or so sets here that need recapping so I'm going to order up lots of caps in the next few days, from all these places justradios.com seems the cheapest, so I'll probably try and get what I can from them. I also remember from my earlier thread that the sprague electrolytics were highly thought of, so it might be worth seeing who has those specifically. I don't know, I'm confused, I used to get all my caps from a guy with a shop about 5 miles from here, and life was easy, but he closed up shop 2 years ago, and my stash of caps has run out.

[Carmine]

Geez, I didn't think finding them was going to be such a PIA. Everybody is always "I recapped this set before breakfast and did the convergence after lunch"... Cripes, I can't find half the stuff I need to even get started. Ordering from different sources is just gonna net me a bunch of needless shipping charges.

[drh4683]

450's will not be a problem. B+ in that set doesnt go over 390 V. Even when you turn on the set, the B+ will not surge over. You still have a 60 volt over buffer zone. The 450's are plentiful and cheaper. Win win situation.

[Carmine]

That would certainly open up a lot more choices.

[Carmine]

Any reason I can't use a 100mfd 250v cap, + two 30mfd 450v caps to replace:

160mfd 250v volt

[Carmine]

OK, FWIW here's what I ordered. If anybody wants to check it over for mistakes, be my guest.


Item Name: 40 mfd at 160 Volts Axial E-Cap (1)
Quantity: 1

Total: $1.19 USD



Item Name: 50 mfd at 450 Volts Axial E-Cap (2 required)
Quantity: 2

Total: $6.98 USD



Item Name: 100 mfd at 450 Volts Axial E-Cap (Two 160mfds required, will add (2) 30mfds for 160)
Quantity: 2

Total: $7.98 USD



Item Name: 40 mfd at 450 Volts Axial E-Cap (One 80mfd required, two in parallel)
Quantity: 2

Total: $5.98 USD



Item Name: 30 mfd at 450 Volts Axial E-Cap (to be added to 100mfd)
Quantity: 4

Total: $7.96 USD



Item Name: 100 mfd at 50 Volts Axial E-Cap (2=200mfd)
Quantity: 2

Total: $1.30 USD



Item Name: 1.0 mfd at 630V Orange Dip ( (2) 4mfds required, will use 4 1mfd in parallel)
Item Number: DME105K630V

Quantity: 8

Total: $11.12 USD



Cart Subtotal: $42.51 USD
Shipping: $3.90 USD
Sales Tax:
Cart Total: $46.41 USD

[roundscreen]

Drh4683 is right, You can use 450 volt caps. If you still don't feel right about it, Hook up your volt meter and check the voltage on the caps. Turn your set on and let it warm up, Then cut it off. Hook up the meter and turn back on.
Then you will see the surge voltage when you turn it back on.
I did that when I did a recap on a zenith 29jc20 chassis. New caps can take a good amount of surge voltage. Also you can add up the value of a cap anyway you like. Just try and stay as close as you can to the original value.

[Carmine]

If you all say it's ok, I'll give it a whack.

If my house burns down while I'm watching Green Acres DVDs, I'm coming to see youse.

[roundscreen]

Put a fuse on the ac interlock and you won't have to worry about that.
It is not fun when the tv starts the house on fire. Been there..

[Bill R]

I don't think 4 orange drops in parallel would work for a 4mfd electrolytic cap. Orange drops are not electrolytic. I don't think they are polarized even though they have one end marked. I think the mark just indicates which lead is connected to the foil in the cap. Then again memory isn't what it used to be either Unless they are controlling frequency most of those caps are probably not that critical value wise. I would use the closest value at the same or higher voltage. Only exception would be the 4 at 475 for that I would use a 450 volt cap.

Bill R