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  #16  
Old 03-10-2011, 12:13 PM
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Quote:
Originally Posted by skillybob View Post
Yes, that's it. I will try to glue it together as best as I can, but I may take up your suggestion and make a new one. Is there a way to test the deflection coils. I can trace the wire leads and unsolder for a continuity test. I don't know if there is anything else I can do for test purposes. I have a few very small 'shiners' of wire on the front. Can I place something like lacquer on them for protection?
There are specific testers for flybacks and yokes like the Eico 944. If you don't have one, you can check the resistance like you said.

Shiners are spots where the wire lacquer has worn off ? I imagine lacquer would work, but I've never tried it.
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  #17  
Old 03-10-2011, 12:46 PM
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Reece's comment about the speaker makes sense to me. I bet that is what is going on. Yes, Bob, there are a few exposed wires at the front of the coil but I can not see anything like a broken wire. Continuity check should tell me . I was thinking of using a product called Corona Dope- just to give those spots a bit of protection.
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  #18  
Old 03-11-2011, 01:08 PM
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I got a partial order of capacitors in from Mouser and thought I would try my hand at stuffing on of the e-caps . The one I choose is mounted under the chassis and is not visible and very easy to get at. The cap is an aluminum can but is covered in a cardboard tube. Just two 40mf at 250v. I pulled the cap off of the chassis and the tube came off easily as it was just stuck on with a bit of black goop. The schematic and the cardboard tube both indicate that these caps are both 40mf but embossed on the aluminum can are 100mf and 30mf. I just thought that this is a bit odd. Anybody else run into this ? I will be replacing the caps with what is on the schematic. Just curious.
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  #19  
Old 03-11-2011, 01:14 PM
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Give me a couple hours and I'll take a look at mine. I got my set over a year ago and have never pulled the chassis. You've got me curious to see what condition it's in.
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  #20  
Old 03-11-2011, 02:46 PM
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My cap says 40 & 40 @ 250v on the cardboard. Measured actual 39 & 47uf in circuit. Can't easily get the cardboard off.

Kevin
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  #21  
Old 03-11-2011, 04:19 PM
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Mine is 40 & 40 @ 250v too. Here are some pictures I took: http://www.flickr.com/photos/7003980...914784/detail/
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  #22  
Old 03-11-2011, 04:43 PM
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Wow, that chassis is clean. I really like those wood floors in your house.

Kevin
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  #23  
Old 03-11-2011, 04:47 PM
skillybob skillybob is offline
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That's good to know. I ordered caps from Mouser (Nichicon PZ's) but they are being sent in two separate orders . The ones I have coming are 47mf's at 450. I guess a little more voltage won't hurt.
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  #24  
Old 03-11-2011, 09:38 PM
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Wow, that chassis is clean. I really like those wood floors in your house.

Kevin
Yeah, I was surprised too. I'm used to more rust and grime. Those floors are from the 1870s. I wish it was my house, but I'm just renting.

Quote:
Originally Posted by skillybob View Post
That's good to know. I ordered caps from Mouser (Nichicon PZ's) but they are being sent in two separate orders . The ones I have coming are 47mf's at 450. I guess a little more voltage won't hurt.
Those are good quality caps and more voltage is no problem.
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  #25  
Old 03-13-2011, 08:13 PM
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Another question has come up. The image shows a pot that is used for the focus control. The pot is rated at 4 watts and 1350 ohms and is wire wound. The pot is apparently sealed and I was wondering if there is a way to clean it properly? The back of the pot looks like it is press fit or maybe welded on( hard to tell). I don't want to damage this part by taking it apart improperly. All of the other controls have a place that is open on the body of the pot to spray in deoxit and should not be a problem. Maybe I should leave well enough alone, but since I have the chassis torn down I thought this would be the time for cleaning. On the other side of the pot there is a brass shaft where I could spray a bit of deox but It does not seem like I would do very much good. Any opinions?
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  #26  
Old 03-13-2011, 10:55 PM
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I'd leave it alone. I've yet to encounter a wire-wound focus pot that needed cleaning.
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  #27  
Old 03-13-2011, 11:48 PM
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I sometimes wonder about everyone using Deoxit on carbon track pots. Is that really the correct thing to clean them with? My fear would be that it could mistake the carbon track for an oxide. Apparently it does work.

Kevin
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  #28  
Old 03-14-2011, 12:19 AM
skillybob skillybob is offline
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Well, you know. I'm certainly no expert but Deoxit seems to be the defacto solution for contact cleaning. Its got my curiosity up, so I'm going to check around and see if I can find anything interesting on the subject. I'm going to leave the pot alone like bandersen suggests and move forward. I'm still waiting on a couple of parts orders so I have plenty of time to get into trouble.
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  #29  
Old 03-14-2011, 02:41 PM
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I went looking on the Caig website. They seem to recommend their D100S (without solvent). But I doubt the solvent would hurt any of the old metal and carbon pots. I just seemed to remember some discussion over on ARF a few years back about it harming the carbon track. I guess I was mistaken. Sorry for the false alarm.

http://store.caig.com/s.nl/ctype.KB/.../.f?category=9

Kevin
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  #30  
Old 03-14-2011, 11:41 PM
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While waiting for an order of caps to come in I thought I would get things ready and pull one of the cans from the chassis to restuff. I unsoldered the leads OK but the caps lugs were twisted over and soldered to the chassis. Not going to happen. My little 60w soldering station won't make a dent in the joint. So - looks like I will be mounting terminal strips instead. I remember when I was younger and getting interested in electronics I had a Weller soldering 'gun'. Long gone , but I think it was about 100 watts or so. Now,that would of come in handy today.
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