Author Topic: WE302 Capacitor - replacement  (Read 668 times)

Offline Fennec

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WE302 Capacitor - replacement
« on: November 13, 2017, 08:05:06 PM »
Hello, forum members:

I have decided to share, and possibly get a feedback on the approach I took with a badly corroded/mangled capacitor in a WE302.

I opted against a donor-maybe-works approach, and since "pure" look here wasn't a concern for me, I decided to make a dimensional replica.
Please see pictures for comparison.

Basically, I took the following:

- 2 uF capacitor, 200V
- 0.47 uF || 0.027 uF (~ 0.5 uF) capacitors, 200V
- Appropriate length of Teflon covered wire (Black, Red, Yellow and Grey in my case)
- Aluminum black anodized tube, oval, 15 mm x 30 mm (almost exact original size)
- Matching oval tube caps

Some soldering, crimping and fitting together - and this is the result. Fits into the bracket nicely, as expected. Because it's black, it is very inconspicuous - it's really hard to see it's there...

Just wanted to share this for collectors, who need a functional "new" capacitor, but are not willing to sacrifice the look :) As a side note, I have seen these capacitors factory painted with grey enamel, so this might be another option to approximate the original appearance.

- Dmitri

Offline cihensley@aol.com

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Re: WE302 Capacitor - replacement
« Reply #1 on: November 13, 2017, 08:24:47 PM »
Very ingenious.

Chuck

Offline HarrySmith

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Re: WE302 Capacitor - replacement
« Reply #2 on: November 13, 2017, 08:39:30 PM »
Very Cool! Great idea. Will you share the inside wiring with us?
Harry Smith
ATCA 4434
TCI

"There is no try,
there is only
do or do not"

Offline Ktownphoneco

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Re: WE302 Capacitor - replacement
« Reply #3 on: November 13, 2017, 09:33:30 PM »
Very good, and a very nice replica of an original.      Good work Dmitri !

Jeff Lamb

Offline Babybearjs

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Re: WE302 Capacitor - replacement
« Reply #4 on: November 14, 2017, 03:03:28 PM »
Interesting solution.... now, can these be made in bulk? or is there a demand for such a thing.... I've had to replace a few in my day....
John

Offline Fennec

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Re: WE302 Capacitor - replacement
« Reply #5 on: November 14, 2017, 04:35:57 PM »
Interesting solution.... now, can these be made in bulk? or is there a demand for such a thing.... I've had to replace a few in my day....

"In bulk" as in batches? Probably yes, provided there is a sufficient demand. The most time consuming feature would be the capacitor holder board - I did everything by hand for this one, and it looks rather... rustic, shall I say :) . And, it took me just over an hour to assemble one from scratch.

However, nothing prevents a person from designing a small PCB with a 4-wire breakout, and ordering it from one of many sources with capacitors already mounted.

In this case it might be worthwhile, since the process would involve crimping spades on the pre-cut wires, soldering them to the terminals, inserting into the tube, and closing both caps - about 15 - 20 min job.

Offline AE_Collector

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Re: WE302 Capacitor - replacement
« Reply #6 on: November 14, 2017, 05:32:20 PM »
Where does one find the pre-made tube and caps? And were they black initially? If they were raw aluminum color they would be just about perfect.

Terry
« Last Edit: November 14, 2017, 05:45:55 PM by AE_Collector »

Offline Fennec

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Re: WE302 Capacitor - replacement
« Reply #7 on: November 14, 2017, 06:17:23 PM »
Where does one find the pre-made tube and caps? And were they black initially? If they were raw aluminum color they would be just about perfect.

Terry

1. Frankly, took me quite a while to find both the tube and caps, but I can share my sources :)
2. No, tube and caps were black from the get go
3. Yes, one can get also "dull aluminum" tube finish, and closest-matching caps can be found in light grey or silver

Granted, tube is not available pre-cut, so one will have to cut it to appropriate length pieces.

- Dmitri
« Last Edit: November 14, 2017, 07:40:39 PM by TelePlay »

Offline oldguy

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Re: WE302 Capacitor - replacement
« Reply #8 on: November 14, 2017, 07:20:45 PM »
Thanks for sharing Dmitry. It's good to hear other peoples solutions to phone problems, so we can apply them to our own repairs when needed.
Do 302 capacitors fail often? all the ones I test come out about 2.0uF & 0.5uF.
Gary

Offline Fennec

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Re: WE302 Capacitor - replacement
« Reply #9 on: November 14, 2017, 08:22:59 PM »
Thanks for sharing Dmitry. It's good to hear other peoples solutions to phone problems, so we can apply them to our own repairs when needed.
Do 302 capacitors fail often? all the ones I test come out about 2.0uF & 0.5uF.

What I have found is that these caps over time get "leaky" - they still measure close to the nominal value, but contribute to the "noise" on the line.
It is more true for the voice circuit cap, but if I am to replace one, I might as well replace both :)

Insofar as sources for tubes and caps go, there are several to chose from. I have settled on the following, primarily due to cost and proximity:

Tube: http://handyct.com/index.php?route=product/product&path=178&product_id=17374
Caps: https://www.amazon.com/Tube-End-Cap-TOOGOO-Plastic/dp/B01G6OYOH8

- Dmitri

Offline Fennec

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Re: WE302 Capacitor - replacement
« Reply #10 on: November 16, 2017, 06:18:49 PM »
Very good, and a very nice replica of an original.      Good work Dmitri !

Jeff Lamb

Thanks, Jeff :) I might entertain making a pre-populated PCB - doing everything manually is rather tedious...

Offline Babybearjs

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Re: WE302 Capacitor - replacement
« Reply #11 on: December 27, 2017, 10:57:22 PM »
I am reminded about the 400 series key phones. these use the same part, except there is a Slate/red wire attached to the case as a ground.... I don't know if this version is really needed.. but I thought I'd mention it....
John

Offline Fennec

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Re: WE302 Capacitor - replacement
« Reply #12 on: December 28, 2017, 09:57:00 PM »
OK, here is my first run of PCB, populated by yours truly, 2uF and 0.5uF.

Both front and back are shown, wire breakouts on the edge. Please see fit into the tube.

Thoughts? Comments? Any interest?