DIY patch cables, major signal loss - what gives??

[joel_ostrom]

I was making some patch cables to connect the pedals on my board with some low profile switchcraft input jacks and Canare GS-4. I tested two of them after they were finished and there was a significant signal loss.

It doesn't make sense, i used the same cable to make a different patch cable and there was no change in signal.

Could it be bad jacks?
Did I wreck the jacks somehow during the soldering process? Or the cable?

I was using a lot of heat on the soldering iron so that I could get the solder to adhere to the inside of the flat part of the jack (for grounding). Could this have done something to wreck the jack?

Anybody have any ideas?

[Enzo]

Maybe too much heat and the inner insulation melted, letting the inner conductor touch the shield.

Measure resistance from tip to sleeve.

I don't know the wire, so... Does this have a layer of conductive black plastic around the inner conductor insulation but under the shield wrap? Is it touching the center anywhere?

prepare the plug. No wire, just heat the place on the plug you want, and melt a little pool of solder. Tin the ground wire on the cable end. Now heat the pool to remelt it. When it flows, push the tined wire into it, and keep heat on only long enough to inside it wets the wire than remove. That will not subject the wire insulation to the extra heat needed to warm up the jack walls.

[joel_ostrom]

Yes, the Canare cable does have a black plastic under the shield wrap. Perhaps it is conductive and causing signal degradation. I'll go back tomorrow and double check that I keep that from touching the center and see if that changes things.

Thanks for the suggestion

[Mick Bailey]

+1 on the conductive plastic. It doesn't short right out, but gives a low-ish resistance across the jack it if touches the centre connection.

[Paleo Pete]

+1 on enzo's soldering method. I use my 100/140 Weller gun for those and keep the grounding solder spot as far away from the center as possible, and use the same method he described. The higher power gun seems to heat it quick enough it doesn't have time to spread as much as with the 25-30 watt pencil irons even though it produces more heat overall. I tin everything, period and use some paste flux, that helps too. I also find a fingernail file helps a lot, solder doesn't like to stick to the smooth chrome finish. Rough it up some first and it works a lot better. I use the fine grit foam board type, 180 or finer. I keep a couple in my soldering kit. I tried soldering the ground onto the cap instead of the bottom, that didn't work as well.

[Enzo]

The black plastic sheath is indeed conductive, it is supposed to be, it is part of the shielding. So you have to treat it like it was wire, not insulation. Keep it away from the conductor. If it touches, it will ground off the signal.