Fun with epoxy resin

Mar 13, 2009 32 Replies

It was in New Zealand in about 1968. In those days there were horrendous charges for nationwide toll calls, so the power company (there was only one, the NZED) ran their own telephone lines. Of course there were 110kV/220kV wires as well but the telephone lines wouldn't go anywhere near those! These days nationwide calls are negligible in cost, and they'd use fibre anyway.

No it's just a commercial secret which I discovered! However I should probably give it away before too much longer. So what use is a high- quality audio transformer these days?

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Matty F saying something like:

If by 'very clever', you mean 'have seen them before and are not psychic', then no.

"Moderately clever" could include spotting that the answer has already been correctly guessed and confirmed.

Predominantly on lv but there were isolated instances where they're on 11kv lines. If they are attached to 11kv circuits, the steelwork at the top of the pole is earthed. Never on 33kv - although there are a few dual circuit lines where multicore protection circuits are slung as a catenary beneath the power circuits.

One of the regulars on uk.telecom ~20 years ago had an incident where their phone cable snapped in bad weather someway down the road, and the loose end blew onto 33kV conductors (not on the same pole). Their phone and several other things blew up, but they were unharmed. There was a Health and Safety investigation of the incident.

Because it was used for simultaneous multiple calls with a carrier group system.

In article , Matty F scribeth thus

Electrostatic speakers 'tho they don't need -that- many volts!..

Actually it wasn't. But I was referring to the special core design which allowed it to pass frequencies of up to 100,000 Hz. I'm no expert on audio transformers but I'm told that they usually start dropping off above 20,000 to 30,000 Hz.

That's a thought. But surely a conventional audio transformer should be able to do the job OK.

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Matty F saying something like:

Sorry, it doesn't detract from the fatuousness of the question.

Here's the arrangement for holding up the wire on a corner:

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clamps on the left hold the wire. The insulator is held within the brass casting. The brass cap on top screws down on the insulator, keeping it rigid. An earthed steel cable is attached to the brass casting at the same height as the wire so that it does not twist. The wire is 600v DC potential.

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