What is this ? - UK Vintage Radio Repair and Restoration Discussion Forum

60 oldjohn · 26th Nov 2021, 5:35 pm

Single coil of 18swg DCC wire measuring 0.3R Only has one fixing point that I can see, where the wires come out.

John.

deswradio · 26th Nov 2021, 6:44 pm

Looks like school physics apparatus to me. It's presumably held vertically so that you can use one of those small plotting compasses to trace magnetic lines of force through the bore of the coil.

Best wishes
Des

60 oldjohn · 26th Nov 2021, 7:36 pm

Hi Des, I did wonder if it was part of a schools Galvanometer. Or DF because it has a copper screen? covering the windings.

John.

David G4EBT · 26th Nov 2021, 9:20 pm

I don't know what it was, but I know what it would be ideal for!

The RF alignment instructions for the Bush DAC90A (for example), calls for a single loop of wire - 8" - 10" to be placed near to the frame aerial.

I've attached a clip from the Bush Datasheet below.

Just a loop of wire clipped to the tip and ground of the signal generator output lead would do, but I made my own loop, with a little stand.

The alignment instructions also call for a 'sensitive output meter' as a visual indicator'.

I made Paul Stenning's neat simple little output meter - ideal for that purpose, but irrelevant to this thread.

joebog1 · 26th Nov 2021, 9:22 pm

I think its a screened search coil for a metal detector. I made many over the years and this looks like a screened version.

Joe

26th Nov 2021, 5:35 pm	#1
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,988	What is this ? Single coil of 18swg DCC wire measuring 0.3R Only has one fixing point that I can see, where the wires come out. John. Attached Thumbnails __________________ My favourite text message "I'll be there in five minutes, if not read again"

26th Nov 2021, 6:44 pm	#2
deswradio Tetrode Join Date: Sep 2020 Location: Lewes, East Sussex, UK. Posts: 66	Re: What is this ? Looks like school physics apparatus to me. It's presumably held vertically so that you can use one of those small plotting compasses to trace magnetic lines of force through the bore of the coil. Best wishes Des

26th Nov 2021, 7:36 pm	#3
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,988	Re: What is this ? Hi Des, I did wonder if it was part of a schools Galvanometer. Or DF because it has a copper screen? covering the windings. John. __________________ My favourite text message "I'll be there in five minutes, if not read again"

26th Nov 2021, 9:20 pm	#4
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,763	Re: What is this ? I don't know what it was, but I know what it would be ideal for! The RF alignment instructions for the Bush DAC90A (for example), calls for a single loop of wire - 8" - 10" to be placed near to the frame aerial. I've attached a clip from the Bush Datasheet below. Just a loop of wire clipped to the tip and ground of the signal generator output lead would do, but I made my own loop, with a little stand. The alignment instructions also call for a 'sensitive output meter' as a visual indicator'. I made Paul Stenning's neat simple little output meter - ideal for that purpose, but irrelevant to this thread. Attached Thumbnails __________________ David. BVWS Member. G-QRP Club member 1339.

26th Nov 2021, 9:22 pm	#5
joebog1 Banned Join Date: Jun 2015 Location: Mareeba, North Queensland, Australia Posts: 2,704	Re: What is this ? I think its a screened search coil for a metal detector. I made many over the years and this looks like a screened version. Joe