Copper shielded 50 Ohm coax

The braid on the RG58 *should* be tinned copper. It must really be crap if it doesn't take solder.

Andy

The braid on the RG58 *should* be tinned copper. It must really be crap if it doesn't take solder.

Andy

Well the Jaytoy definitely does not! And Altronics say they don't have any copper shielded RG58. Where do you get yours?

any

Email me off-list (change "agw" to "andy") , we have 100's of metres of good quality RG58C/U here.

Andy

you could try cutting up some old coaxial ethernet cables. the last one I cut up had copper shield,

Great idea! I'll have a look.

This type of coax usually has a stranded center conductor as opposed to a solid center conductor. Is that a problem?

Twist the screen and wire together you want to attach and use some of that conductive glue Jaycar have. Works perfectly.

What was the exact label on the cable? The only tme I've seen that type, it was very stiff IBM and they were not "ethernet"

Conductive 'glue'? Sounds very Jaytoy! Or perhaps you were serious? Surely can't be very satisfactory when a good low impednace connection at UHF is required?

It's called cold solder and it does conduct but badly , no where as strong as hot solder either

Oh that stuff, typical Jaytoy! Typical and up there with farting ashtrays and their other junk! Pity about Altronics though. They have been good on other things. I suppose I could raise a mortgage and try Radiospares? They used to be quite reasonable in price many years ago in the UK but perhaps they've been bought by some US entity?

they have conductive demister repair paint (gotta get some to fix my phone keypad)

hmm, UHF thin ethernet has most of the energy between 10 and 20Mhz. the ethernet cable may not work well for UHf.

I don't recall and I have misplaced it.

IBM was using token ring. the wiring as far as I could tell was still 50 ohm coax with BNC connectors,

IBM used RG/62 which is 93 ohm.

A lot of the RG59 cable tv cable is aluminum. Cheaper, lighter. Try a ham-radio store. Depending on how much you want, any ham will probably have some in the attic.

A lot in the later installs was rg59au ( 75hom)

decent coax is easy to find but of course is not free.

That depends on how long it takes you to wreck out an old installation. Sometimes its already piled up beside the dumpster for you. :)

IBM had 2 significantly different systems in widespread use and some others as well.

The 3270 Display System used 93 ohm coax to distribute Video from a controller to all the screens in an office in a STAR configuration.

While the PC Network introduced in the 80s used 75ohm coax in a serial configuration with a terminator at the far end. The prescribed coax was RG-6 (thick heavy lo loss ) for long runs and RG-59 (small flexible hi loss ) for device connectors on the desk.

A later arrival was IBM TokenRing which used twisted pair and a clumsy big black plug that was the same both ends ( there was no male and female).

John G.