BTH C2 speaker coil rewinding? - UK Vintage Radio Repair and Restoration Discussion Forum

Voxophone · 31st May 2017, 2:15 pm

I have a BTH C2 horn loudspeaker in good cosmetic condition; however the coils appear to be open circuit (the design value is 2k) and I'd like to try and rewind them.

Has anyone successfully rewound one of these before? I think the coils are accessible by removing the bottom but I haven’t tried to get at them yet. It would be nice to get it working.

Thanks

Liam

Ed_Dinning · 31st May 2017, 7:51 pm

Hi Liam, I've done these before but they are very fiddly and usually need a jig making to hold them in the winder. Then lots of turns of about 0.05mm wire!

Ed

PJL · 31st May 2017, 8:39 pm

Done quite a few headphones and speaker coils with a very basic jig. They take a little patience but the wire is stronger than you might think (I can barely see it).

Voxophone · 1st Jun 2017, 9:40 am

Thanks for your replies.

It turned out to be a false alarm in the end! Once I got the driver out and measured across the terminals directly it read a healthy 1.8k. So it’s the cable rather than the coil that needs replacing.

I still haven’t tested the speaker as the cork disc around the diaphragm needs fixing back in place. I suppose I could just use a spare OPT as a step-up from the external speaker output of a radio?

31st May 2017, 2:15 pm	#1
Voxophone Hexode Join Date: Oct 2015 Location: Sunderland, Tyne and Wear, UK. Posts: 340	BTH C2 speaker coil rewinding? I have a BTH C2 horn loudspeaker in good cosmetic condition; however the coils appear to be open circuit (the design value is 2k) and I'd like to try and rewind them. Has anyone successfully rewound one of these before? I think the coils are accessible by removing the bottom but I haven’t tried to get at them yet. It would be nice to get it working. Thanks Liam

31st May 2017, 7:51 pm	#2
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: BTH C2 speaker coil rewinding? Hi Liam, I've done these before but they are very fiddly and usually need a jig making to hold them in the winder. Then lots of turns of about 0.05mm wire! Ed

31st May 2017, 8:39 pm	#3
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: BTH C2 speaker coil rewinding? Done quite a few headphones and speaker coils with a very basic jig. They take a little patience but the wire is stronger than you might think (I can barely see it).

1st Jun 2017, 9:40 am	#4
Voxophone Hexode Join Date: Oct 2015 Location: Sunderland, Tyne and Wear, UK. Posts: 340	Re: BTH C2 speaker coil rewinding? Thanks for your replies. It turned out to be a false alarm in the end! Once I got the driver out and measured across the terminals directly it read a healthy 1.8k. So it’s the cable rather than the coil that needs replacing. I still haven’t tested the speaker as the cork disc around the diaphragm needs fixing back in place. I suppose I could just use a spare OPT as a step-up from the external speaker output of a radio?