Not sure what this is

[els1967]

It came with a job lot of GPO spares I bought from Ebay a few years ago. Found it in the attic recently. I thought it was some sort of phone line/lightning protection system but could be wrong. Pretty sure it's European.

Any ideas?

[lesmw0sec]

Yes - it looks like an old style GPO telephone protection box.

[MIKEG4IIA]

From the dim and distant...............I think it was called a "line arrestor" and
was installed in the sub's property (customers were called subscribers, hence subs.).

[russell_w_b]

Originally Posted by els1967

Found it in the attic recently. I thought it was some sort of phone line/lightning protection system but could be wrong.

You're not wrong. It's an old-style UK lightning arrestor fitted on the incoming pair. These units were superseded by a slimmer version mounted on a bakelite base containing a fuse in each line, and slide-in plastic blocks with zig-zag spark gaps between each line and earth.

[russell_w_b]

Originally Posted by russell_w_b

You're not wrong. It's an old-style UK lightning arrestor fitted on the incoming pair. These units were superseded by a slimmer version mounted on a bakelite base containing a fuse in each line, and slide-in plastic blocks with zig-zag spark gaps between each line and earth.

Actually, I might've been wrong about the zig-zag spark gap! Your older unit may have had the zig-zag spark gap from each line to earth (I used to have an identical one I 'recycled' from a derelict house when I was a kid).

I've just looked at mine and it seems the spark-gap is a thin sheet of mica(?) sandwiched between the plastic blocks and designed to break down on flashover. Unless different designs of plug-in spark gap were available, of course. I've had several of these units over the years and memory might be playing tricks.

[Graham G3ZVT]

Looks pristine. I've seen many of these, but usually covered in layers of paint.

[russell_w_b]

Originally Posted by Graham G3ZVT

I've seen many of these, but usually covered in layers of paint.

If it's mine you're on about, Graham, it was never painted. It's from the crypt at the former BBC Skelton TX station and was used on the field-telephone ccts that ran out to all the antenna switches when they were changed manually, back in the '40s, '50s and '60s by a switching TA on a bicycle armed with a field-telephone, a miners' lamp and a long ash pole with a hook on the end.

If you're on about the OPs earlier lightning arrestor then yes... It is indeed in good condition! I've been in many houses where telecomms infrastructure is almost hidden beneath thick layers of paint, almost as if it's an intrusion that shouldn't be visible.

[els1967]

Thanks for all the input. With most GPO equipment I have seen over the years everything seems to have an part number and/or stamped with GPO and typically use bolts or slot headed screws to access the innards. This being the case mine has a knurled knob and rather more "decorative" look to it than most GPO equipment I've ever seen. That's why I thought it wasn't GPO. Does anyone have any more information specifically on my type of model?

Thanks

[Nickthedentist]

https://www.britishtelephones.com/ov...ermination.htm


https://www.britishtelephones.com/ov...ivedevices.htm

[els1967]

Originally Posted by Nickthedentist

https://www.britishtelephones.com/ov...ermination.htm


https://www.britishtelephones.com/ov...ivedevices.htm

Bob on.