EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: lordvader88 on July 15, 2018, 03:29:49 am
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I bought 20 or so wires w/ alligator clips on both ends and they all pretty much measure 0.5-1.5 ohm. They are about 20-22 gauge stranded copper wire I think.
They are not soldered. So that must be just weak connections right....and therefore I should solder the clips....rather than post about it. But it's annoying when the com probe is 100s of mV below PCB gnd.
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Your resistance measurement is slightly high as I expect it to be under 1 ohm but cheapo croc clip leads are just like that. I expect the conductor in the lead is actually thinner than 20AWG and together with not great crimping is the cause for it.
Soldering the crimp on a croc clip lead is not a great idea though. The solder will wick up the wire and cause a weak point there. As you'll most likely be moving the leads around a lot, you'll end up with a break.
Old thread about them (https://www.eevblog.com/forum/reviews/review-of-cheap-ebay-aligator-test-clips/).
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I used to use those cheap alligator clips, but they are crap. The conductor in the wire is just folded back on itself then the alligator clip is squished down. Makes a terrible connection.
Now I just get my own alligator clips (I found some good quality gold plated ones here in Japan) and I make my own leads with silicon wire from ebay.
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The wire could be steel or aluminium
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TERRA Operative is correct. I bought some of those cheap leads and found that a couple of the leads went open circuit and the rest read high for resistance. If I pulled on the two ends, the wire came right out because it was poorly crimped with the wire folded back over the insulation. I also found that the plastic insulating boot was so stiff that it was almost impossible to open the clips. I just tossed those jumpers out and bought some grabber hook type jumpers that had soldered ends.
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For those of us in Japan, these are the alligator clips I use:
http://www.teishin-bel.co.jp/mokuji_kurippu/clup.pdf (http://www.teishin-bel.co.jp/mokuji_kurippu/clup.pdf)
Part numbers C-103-5 and C-101-5
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There are decent clips available in the US as well:
https://muellerelectric.com/product-category/alligator-clips-insulators/ (https://muellerelectric.com/product-category/alligator-clips-insulators/)
Pomona Test Lead wiire:
https://www.amazon.com/Pomona-6733-0-Silicone-Insulation-Temperature/dp/B000ODU7HO (https://www.amazon.com/Pomona-6733-0-Silicone-Insulation-Temperature/dp/B000ODU7HO)
This may be a little over the top and other wire may work just as well:
https://www.jameco.com/z/JMS822-01G-18-AWG-6-Color-Stranded-Tinned-Copper-Hook-Up-Wire-Assortment-25-Feet_2206281.html (https://www.jameco.com/z/JMS822-01G-18-AWG-6-Color-Stranded-Tinned-Copper-Hook-Up-Wire-Assortment-25-Feet_2206281.html)
Even when crap is cheap, it's still crap.
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I had the same experience with cheap clip leads, I burned out several of them and had others fail mechanically. Eventually I ended up buying some 18 awg silicone wire from HobbyKing and got some high quality clips and made my own, they've held up great.
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For those of us in Japan, these are the alligator clips I use:
http://www.teishin-bel.co.jp/mokuji_kurippu/clup.pdf (http://www.teishin-bel.co.jp/mokuji_kurippu/clup.pdf)
Part numbers C-103-5 and C-101-5
I tried to buy Teishin Electric Co. jumpers to replace the ones I have from 30 years ago. They are worth it.
But I can't find Japanese sellers to North America. It would cost $60 alone for DHL from Japan.
chinese ones are crap, they all need to be soldered and the plastic gets hard after a year. I hate their jumpers :rant:
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Found a cheap solution for AWG18 jumpers.. chop 6ft PC power cords (https://www.eevblog.com/forum/beginners/what-is-the-white-powder-inside-computer-iec-power-cords/), then scratch and split outer vinyl with a razor blade.
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Well that's one option if you have a bunch of free power cords, though I do like the silicone wire better. It's smaller (thinner insulation) and more flexible, and you can get it in a rainbow of colors for not much money. Anywhere that sells stuff for RC models will have it.
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There are decent clips available in the US as well:
https://muellerelectric.com/product-category/alligator-clips-insulators/ (https://muellerelectric.com/product-category/alligator-clips-insulators/)
Those Mueller clips are great I have a bunch of them that are years old, they're going strong and they're easily available here in the UK at a decent price.