Unsolderable wire?

If it's like this cr*p they sell at Home Despot, it's copper clad steel core with an _aluminum_ braid shield:-

That would explain the copper-like heat conduction that you're observing.

I suppose you could try an aluminum flux, but can't you just unravel and gather enough of the shield to crimp into a ring terminal or something?

Best regards, Spehro Pefhany

It's not made to be soldered. It's CATV cable that's made for crimp on 'F' fittings.

"Bob E."

.... Phil

Twist the braid into a wire and butt splice on a copper wire. Heat shrink over it.

Yes it's that crap.

Yeah, that's my next move. I just couldn't believe that something couldn't be soldered. I guess REALLY agressive flux is required, as you say.

When it comes to broadcast TV I try to solder every connection possible. Every crimp is one more dB lost.

Thanks.

Crimps in hand...

I guess there's always better stuff like this:-

Best regards, Spehro Pefhany

You must do lousy crimping, if you lose a dB.

I would have thought every soldered joint is one more reflection.

I'm no RF expert, just my impression--possibly mistaken.

Thanks.

The loss should be under .1 dB for a good F connector, ant they are used into the GHz range.

yeah stainless steel braid, aluminium shield and a copper-plated steel core. most of the RG6 I've used is like that.

a solderable F connector socket is probably the best way to terminate it.

Give up! If you can't give up spot weld it to some tinned copper.

If it's for personal use, tightly wrap a dozen turns of tinned copper wire (or silver plated) around the braid, twist the end together and solder to these.

Cheers

Aluminum is a poor choice for a crimped connection. Remember the problems with household aluminum wiring -- even when it was screwed down?

Electroplated wire, most likely nickel. Jamie

Well, what does it feel like?

Steel wire feels very stiff. Grab a leaded component out of the box and ponder the leads; they're probably tin plated steel (check with a magnet). Most resistors, capacitors and diodes are. Some smaller ceramic caps have thicker, softer copper leads; find some if you can.

Aluminum wire is very soft, floppy stuff. It is much softer than copper, than copper is of steel. If that's what it is... oh well.

As for soldering practice... the old saw about "apply solder to the opposite side of the joint" is complete BS. Forget about it. Don't try soldering as you were told, make the solder happy and good joints will follow. First goal, get the part hot: hold the iron on the part, and apply solder right beside the iron, or to it, so the iron heats and wets what it's touching. On a braid, solder will spread and soon the joint will accept solder from all sides.

Tim

-- Seven Transistor Labs Electrical Engineering Consultation Website:

A solder pot is preferred. Otherwise burn all the non-metallic weirdness away with your trusty Zippo.

Michael A. Terrell scribbled thus:

I agree ! A good crimp is at least as good as the best solder joint.

Its virtually impossible to tin polyethylene coax braid without softening the dielectric. It will re-solidify. PTFE (Teflon) is better in that respect.

If you think the braid is steel, try it with a magnet.

From a quick look at Belden specs, they, at least, don't make any RG6 types with steel braid. There are some versions with aluminum braid.

If it's aluminum, you can't. Either get some cable with tinned or silver plated copper braid, or put a BNC socket on the PCB, and a crimp BNC on the cable. (I don't trust crimping to aluminum, BTW, there's a metallurgical creep problem)