New Philco 20 Filter Caps...In, but Another Question??
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It could be that you are drawing additional curent, possibly through an un-replaced cap down the line.
Agree, finish the re-cap, then address the power resistor issue.
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That makes excellent sense. Thanks!!
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Current.....
Jeez, my teachers learned me good.
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TA.....no problem...I understood your post very clearly
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I'll mention in passing that it is important that the input filter cap (#26 pins 1-2) should not exceed the capacitance value of the original. If it does it can give you a much higher plate volt than is shown on the diagram and will cause the B/C resistor to get very hot!!!
Terry
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I'm almost done recapping, BUT, I need to know what the values and voltage ratings are of the filter caps (26), between pins 1 & 2, 2 & 6, 1 & 4, 1 & 3 . THANKS!!
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Schematic not the best, but I think you would be OK with 10 watts ---- if there is nothing else dragging the rest of the voltage divider down. You will know better once you recap and recarb the set. If you have an analog 250 or 500 ma DCmilliampemer you can see just how much current this resistor is drawing by putting it in seriees with the hot resistor l (+ side to B+. ) I wouldn't expect to see more than 30-50 at most ma load from there. If there's more, something is wrong down the line. But do completely recap first at very least.
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As for the capacitors in the multi-cap can...it would be best if you use yellow metalized film caps rated at 600 WVDC. You can use electrolytics rated at 450 WVDC for the 1 and 1.5 uF caps but they will not last as long.
--
Ron Ramirez
Ferdinand IN
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Thanks for all your help on this so far guys. I'm going to order the caps, and from reading other posts, I know how to open the can and wire the caps inside when I get them. Learned a lot so far. Thanks again!!
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Hello.......Found Metalized Polypropylene, 630V, aluminum metalized polypropylene film capacitors on Antique Electronic Supplies web site. They have 1.0 1.5 & .15 Will these do?...THANKS!!
(This post was last modified: 01-19-2013, 10:58 AM by Joe.)
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Thanks TA...I'll order them now. P.S. Got the top of the can off, with the base still wired and intact. I can clean the can out while I wait for the caps. So far so good. THANKS AGAIN!!
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Hey Joe
I might have a spare B/C resistor if you need it. Awhile back I ended up with a few extra 20 chassis... Tnx Tom and others.
Terry
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Words of wisdom and lessons learned-take plenty of pictures before you disconnect those wires for recapping. I managed to stuff mine with standard orange drops at 630v but it was tight. 450v electrolytics would have given much more room but as Ron indicated, the longevity wouldn't be as good. This is what the wiring looked like inside the can on mine before snipping and removing some of the tar to have room to fit the caps.
[Image: http://i180.photobucket.com/albums/x220/...EF4684.jpg]
[Image: http://i180.photobucket.com/albums/x220/...F4682a.jpg]
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Hello All.....
Want to say up front...thanks for all the posts and help. Here is where I am now. New caps came. Took top of can off, clipped all old wires from the old caps and lifted the can out, leaving the bottom part of the can in; also leaving all the wiring in place under the can. (Did not have to touch that)! So now have 1mf across 1 & 2, 1mf across 1 & 4, 1.5mf actoss 1 & 3, 0.15uf across 2 & 6. (Again, old caps completely out of the circuit). The caps are rated at 630v. P late voltages all within speck. The 10 watt power resistor across b/c pins 1&2 still gets hot to the touch. There is 55vdc across it, and putting an amp meter in series, it is drawing about 33ma. This is the olny component hot to the touch. I have had the radio on now for 5 hours, running like a champ! Aligned it at 1400 on the dial, and the dial tracks. Should I put in a 20 watt 1500 ohm resister, or just snug the 10 watt against the chassis as a heat sink? The resistor has not gotten any hotter. Thanks again everyone. Joe
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