What is this and should I replace it?  - Page 1
Forum section: electronics / repair

author: DaneH3
author_rank: Contributor
timestamp: September 29, 2018, 08:46:33 pm
content: So I was taking apart my Icom IC-24AT to do the last repair on it, and due to my ignorance, snapped some small wires going from one fragile board to another.The image attached shows them. I'm not sure what thewhite bits around the wireare, but my assumption is they are some kind of choke meant to keep radio frequencies from screwing with the power lines.The real question is,should I bother replacing them? What should I search for to find a valid replacement?Just wondering, since I could easily just put in a normal wire instead.Thanks,Dane

author: ataradov
author_rank: Super Contributor
timestamp: September 29, 2018, 09:00:36 pm
content: I think your assumption is correct. And the thinking of replacing them with wires is also correct. Don't overthink it.

author: DaJMasta
author_rank: Super Contributor
timestamp: September 29, 2018, 09:05:22 pm
content: I dunno, it could be but it looks like it's something potted in a ceramic shell? Have you hit the ends with a multimeter? Some resistors are packaged with that method, but it doesn't really look like one to me.If you've got a multimeter and an LCR meter, you should be able to determine pretty well what sort of thing it is, if it were still operating. low value resistance with a little more inductance than a similar length of wire is probably a ferrite or a choke, just resistor would measure as such, capacitor would be easy to ID, and could diode check as well.

author: DaneH3
author_rank: Contributor
timestamp: September 29, 2018, 09:10:13 pm
content: Quote from: ataradov on September 29, 2018, 09:00:36 pmI assumed I was overthinking, sort of. Better safe than sorry, however.Replacing the wires with more flexible ones would reduce the chance of breaking them again, anyway.Quote from: DaJMasta on September 29, 2018, 09:05:22 pmI hooked it up to my LCR meter and it showed as a .1 Ohm resistor, but I double checked and that's just what the LCR shows when it's shorted.Doesn't look like anything's potted in there.

author: DaJMasta
author_rank: Super Contributor
timestamp: September 29, 2018, 09:32:25 pm
content: If you crank up the frequency on the LCR (if it goes up), then you're more likely to be able to see a small inductor or a ferrite. Just looked potted to me because the top one in the pic has a shade of white on the outside, then a slightly offwhite center around the lead - a little like a potted thing.

author: DaneH3
author_rank: Contributor
timestamp: September 29, 2018, 09:35:46 pm
content: Quote from: DaJMasta on September 29, 2018, 09:32:25 pmIt's by no means a fancy LCR. Nothing a can really change to get a better reading.

author: David Hess
author_rank: Super Contributor
timestamp: September 30, 2018, 03:27:58 am
content: It is just an insulated jumper. Replace it with a wire.

author: TheSteve
author_rank: Unknown
timestamp: September 30, 2018, 04:59:02 am
content: I also think they are blobs of plastic or something so that the wires can never move and short to each other.

author: DaneH3
author_rank: Contributor
timestamp: September 30, 2018, 05:48:19 am
content: Replaced the wires with some I had. Works great.Thanks guys,Dane

author: SeanB
author_rank: Super Contributor
timestamp: September 30, 2018, 12:03:03 pm
content: Those are zero ohm resistors, which were shaped that way so that an auto insertion machine could handle them like a regular 0.25W resistor on a PCB. Used here as insulated wire links, probably as they both provide insulation between wires, are capable of handling 2A and also most likely Icom has a few hundred reels of them sitting in a store, and they are being used as they are both human insertable, or can be handled by the auto inserter as well.