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Orange Cap Disease / Cap disease

tpr - 2008-11-29 16:16

Orange Cap Disease / Cap Disease
What is it? Mostly the orange types are defective, others could be defective by usual aging.
Orange Capacitor Disease is unofficial name given to the failure of little orange metalized polypropylene capacitors that are used in many tape decks. For some unknown reason these capacitors are very prone to failure and usually result in rustling, crackling or lack of audio in one, or sometimes both channels. When an orange capacitor fails in a tape decks bias oscillator, the usual result is an ability to erase, low record level in both channels and/or a varying of the record level. The ultimate solution would be to go through your deck and replace all the orange capacitors. But, that would require a full electrical calibration. The more practical solution is to replace only the bad cap(s), but, finding the one or two caps that are bad isn't easy. But narrowing it down to the section isn't too bad. The bias circuits and the Dolby circuits are usually the most prone to develop problems.And be aware:the following caps are NOT MEANT:



--------------------------------------------but these: and these:

tpr - 2008-11-29 16:19

What are suitable replacement components?
The prefered replacement capacitor are polypropylene because of their sonic qualities, but, polyester or polystyrene have been used with success and no noticeable degradation of sound quality. The replacement capacitors should have a voltage ratings of at least 50 Volts except for ones used in the bias oscillator which should have a rating of 100 Volts or highier.

The tolerance is the first letter following the 3 digit value. The letter J indicates 5% tolerance, K indicates 10% and I think the G indicates either 2%. I need to research that one.

One good candidate is the Panasonic ECQ-P (Z) series polypropylene caps that are carried by Digikey. They run about $0.23-0.60 depending on value. Another good candidate are Panasonic ECQ-B series polyester caps. They are similar in size to the original are very inexpensive. For the 100V caps you should the ECQ-B series (because the ECQ-P caps don't come in 100V). One of the best caps are the green Matsus:hita caps. I'm not sure who carries these.

Another place to get caps is Mouser They carry AVX, Vishay, Wima and Xicon. Try the BQ-series polyester film caps from AVX, the MKT1817 and MKT1818 polyester film caps from Vishay or the MKP2 polypropylene film and MKS2 polyester film caps from Wima. Most of these series aren't very complete (may have missing values that you need). The most complete series at Mouser is the Xicon PF series.

Newark also has caps, but, I don't like their web site and have a hard time finding what I need over there. They carry the Cornell Dubilier caps, the AVX BQ-series and Vishay MKT371 serues polyester caps.

How to determine the capacitors value. The caps are usually labeled with a three digits and two letters. The first two digits are the value and the third is the number of zeros to give you the value in pF. For example 561 = 560pf or 0.00056uF, 332 = 3300pF or 0.0033uF and 683 = 68000pf or 0.068uF. Don't worry about the last two characters. I think they are the voltage rating and/or tolerance.

chilinvilin - 2008-11-30 20:48

Good information. Thank you...

billpc55 - 2008-11-30 20:56

this is something which i worry about. i have some very nice boomboxes. i also have some extremely valuable other things which are filled with these little basturds.

ford93 - 2008-11-30 22:46

My Telefunken has one bad speaker channel, funny thing it worked for awhile and I got to listen how this monster sound.

Now getting back from work I turned her on and what do you know the speaker channel is doing that static noise again. I know it's these little pain in the arse thats causing this problem.

So I'm bummed out Frown because I thought she recouped from Deoxit spraying the channel. I hope a Technician which was referred to me by JT will be able to fix this problem.

moncheeto - 2008-12-01 02:41

well caps should be the main concern as they age they start to lose values,dry up or short out in the case of the electroyic caps so with that said we should be ready Nod Yes

ford93 - 2008-12-01 08:46

Forgot to mentioned on that speaker channel there is some green goowy stuff it's noticeable when pulling out the speaker jack.

I sprayed some Deoxit after awhile sound started coming out from that channel but only temporary.

Does anybody has a suggestion what do in this case besides Deoxit I mean I must have sprayed about four times and the channel only works for a short moment. Frown

jvc.floyd - 2008-12-01 08:58

that is called dielectric grease its an electicaly concuctive grease that keeps moister out of the socket and helps make a more solid connection its the same almost as the grease used on spark plug boots to keep water out of them.

ford93 - 2008-12-01 09:04

Why is it when I spray Deoxit I get sound only for a moment.

If this is the case of a grease used to conduct a more solid connection should I use spark plug grease for this type of application?

tpr - 2008-12-01 10:03

quote:
I sprayed some Deoxit after awhile

OHO! Eek Wink
Better you don`t do that again!

That could indeed accure a short! Nod Yes


ford93 - 2008-12-01 10:36

Thanks for that advice TPR so far she's OK I'm going to have her serviced. This box sounds sweet when both channels are in operation I'm keeping my fingers crossed that the Tech. guy can fix her.

71spud - 2008-12-01 11:08

He probably just uses this....

- 2008-12-02 03:31

*TPR*Digikey and Mouser are indeed two great sources for all electronic parts.
It is not only the orange caps,as vintage electronic components approach the 30 year mark
it is just a matter of time till all the caps start dropping like fliesBig Grin
Ur boombox is basically a ticking time bomb.

tpr - 2008-12-02 05:49

Yes you are right,I mentioned that above:
quote:
Mostly the orange types are defective, others could be defective by usual aging.



A lot of capacitors will change their electric-value and will be defective after a couple of years,yes.

Different factors could accure damaging the capacitors:
irregularities of the ac tension,as in temperature, or under-inflation too often changing with overinflation or combinations of these factors could be reasons of the damages as well.But as mentioned above as well:the origin of the damages are not researched enough to get reliable ,veryfied results.
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fyj2972 - 2008-12-08 20:25

Newer Matsu****a Mylar cap will take care thise issue for sure.

jerryjg - 2009-12-05 19:56

there is some high end cassette deck that is notorious for the orange cap syndrome. nakawhochi? nakawechi? nakayouchi? nakahechi? Nakashechi?

lav.loo - 2010-09-13 15:32

Eek Eek Eek this is news i never wanted to hear, it,s common sense that nothing can defy the ageing with time process, but to hear that these capacitors will all disintigrate in the near future is a bummer Nod Yes
on the other hand i would,nt want them to outlive me Big Grin

macdude443 - 2011-03-17 19:28

The information in the first post is from this page regarding Nakamichi cassette decks: 
http://www.nakremotes.com/Geo/...ange%20Cap%20Disease

I'm not sure if those voltage specs are the same for the general boombox, but I guess in most situations a 100volt cap couldn't hurt.  The codes are a total PITA to read though.