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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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17th Aug 2019, 3:28 pm | #1 |
Heptode
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 728
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Advice on rewinding Telsen Dual Range Aerial Coil
I am finally getting around to assembling my Telsen Conqueror Three (featured in the Telsen Radiomag), which is a straight three valve TRF receiver and the homebrew version of Telsen's Victor 3. However, in order to complete the job I need to fix the aerial coil shown in the pictures.
It is a Telsen Dual Range Aerial Coil type W.76 and as you can see it employs two different gauges of cotton covered wire, the thinner one of which is broken in several places. I can probably work out the winding arrangement and how many turns for each, but I don't know the two wire gauges which were employed and whether it's still possible to get equivalents. Can anyone tell me? I will likely need to disassemble the unit because the integrated tuning condenser is almost certainly in need of a thorough clean so I might as well rewind from scratch. Thanks, Nick |
17th Aug 2019, 4:49 pm | #2 |
Dekatron
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 7,061
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
Unwind a reasonable length (couple of metres), and measure the resistance. Wire tables will enable you to find the gauge then.
Modern enamel-covered wire will be better than silk or cotton-covered stuff, and won't look as out of place as you might think. It is barely possible that the untuned aerial coil is wound with resistance wire (to kill any unwanted resonances) so cross-checking with a micrometer is advisable. Where can you get wire? Scientific Wire Co (Google them). Last edited by kalee20; 17th Aug 2019 at 4:50 pm. Reason: Last para |
17th Aug 2019, 7:37 pm | #3 |
Dekatron
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,173
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
Hi Nick, long time no hear.
If you fancy a trip to this side of the UK I can probably assist as I have a good selection of wire and have used those and similar coils in the past. If you have more of those coils you could easily modify one of then for SW use as it uses many fewer turns. Failing that we my be over there in mid oct if you fancy meeting up. Cheers, Ed |
17th Aug 2019, 7:56 pm | #4 |
Heptode
Join Date: Dec 2014
Location: Lincoln, Lincolnshire, UK.
Posts: 583
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
It might be worth just reading through a few Practical Wireless from the period to get a feel for what you are planning to do (American Radio History site). There may be some additional information on your particular unit.
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17th Aug 2019, 9:14 pm | #5 | |
Heptode
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 728
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
Quote:
I would love to meet up and also take you up on the offer of assistance. I have sent you a PM. Nick. |
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17th Aug 2019, 9:17 pm | #6 |
Heptode
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 728
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
Thanks I might just do that, although if anyone is interested there is detailed information in issue 1 of the Telsen Radiomag.
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19th Aug 2019, 5:40 pm | #7 |
Heptode
Join Date: Apr 2014
Location: Wigton, Cumbria, UK.
Posts: 728
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Re: Advice on rewinding Telsen Dual Range Aerial Coil
Thought I'd report back regarding the wire for this Telsen coil.
Using a micrometer I found the wire for the LW winding to be 0.19mm, which is circa 36 SWG, and the wire for SW winding to be 0.43mm, which falls between 27 and 26 SWG. As far as I can tell the original is standard silk or cotton covered copper wire and by happy coincidence I have some 0.45mm cotton covered so that sorts out the SW winding, and wires.co.uk do a 0.2mm silk covered copper wire, so I should be able to rewind it close to the original spec. I even have some green fabric dye |