Weyrad coil - UK Vintage Radio Repair and Restoration Discussion Forum

Ed_Dinning · 25th Mar 2014, 10:06 pm

Hi Folks, can anyone help identify some Weyrad coils I have?
These are all marked L207, some with the Weyrad logo as well. they are a 12mm square copper can about 18mm high and are small pot cores on a plastic former with a dust core.
they have a single winding, approx. 4mH and 44R.
base is 6 pin for PCB mounting, with one pair of pins slightly further away from the others for polarisation.

Thanks, Ed

Biggles · 27th Mar 2014, 8:39 pm

Hi Ed, they sound like possible TV types to me. I'm sure I heard that Weyrad made deflection yokes etc for the TV industry in later years but I may be wrong. 4mH would suggest quite a low working frequency though. They may resonate at Long wave frequencies with a suitable parallel capacitor...
Alan.

Ed_Dinning · 27th Mar 2014, 8:43 pm

Hi Alan, thanks for that. L207 does sound like a circuit ref on a PCB and I have got qiute a few of them, possibly left from a production run.

Ed

Biggles · 27th Mar 2014, 8:55 pm

You'll now have to design a project to use them. That's what usually happens here. I find a nice component then work out a way of using it. L207 does sound like a pcb component reference, and the high? number may suggest quite a few components on the board. Just a thought, they're not pilot tone filter or stereo decoder coils are they?
Alan.

dazzlevision · 27th Mar 2014, 10:36 pm

Hello,

It could be for a Decca colour TV, as Decca owned Weyrad in the 1970s (I believe). They certainly used Weyrad for the supply of a lot of coils, transformers and chokes used in their TV set production.

One would have to scan their TV service manuals for a full ID of your coil. A likely candidate would be their Bradford hybrid CTV chassis.

Posting a photo might help.

Regards,

Dazzlevision

MALC SCOTT · 28th Mar 2014, 12:27 am

Hi Ed, L207 was the 7.8khz ident coil on the Rediffusion MK1 decoder board.

Ed_Dinning · 28th Mar 2014, 9:21 pm

Hi Malc, thanks for that, It was quite high inductance (4mH) and was wound inside a mini pot core so I was guessing it was quite low frequency.

Ed

25th Mar 2014, 10:06 pm	#1
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Weyrad coil Hi Folks, can anyone help identify some Weyrad coils I have? These are all marked L207, some with the Weyrad logo as well. they are a 12mm square copper can about 18mm high and are small pot cores on a plastic former with a dust core. they have a single winding, approx. 4mH and 44R. base is 6 pin for PCB mounting, with one pair of pins slightly further away from the others for polarisation. Thanks, Ed

27th Mar 2014, 8:39 pm	#2
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Re: Weyrad coil Hi Ed, they sound like possible TV types to me. I'm sure I heard that Weyrad made deflection yokes etc for the TV industry in later years but I may be wrong. 4mH would suggest quite a low working frequency though. They may resonate at Long wave frequencies with a suitable parallel capacitor... Alan.

27th Mar 2014, 8:43 pm	#3
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Weyrad coil Hi Alan, thanks for that. L207 does sound like a circuit ref on a PCB and I have got qiute a few of them, possibly left from a production run. Ed

27th Mar 2014, 8:55 pm	#4
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Re: Weyrad coil You'll now have to design a project to use them. That's what usually happens here. I find a nice component then work out a way of using it. L207 does sound like a pcb component reference, and the high? number may suggest quite a few components on the board. Just a thought, they're not pilot tone filter or stereo decoder coils are they? Alan.

27th Mar 2014, 10:36 pm	#5
dazzlevision Dekatron Join Date: Sep 2003 Location: Near Swindon, North Wiltshire, UK. Posts: 3,621	Re: Weyrad coil Hello, It could be for a Decca colour TV, as Decca owned Weyrad in the 1970s (I believe). They certainly used Weyrad for the supply of a lot of coils, transformers and chokes used in their TV set production. One would have to scan their TV service manuals for a full ID of your coil. A likely candidate would be their Bradford hybrid CTV chassis. Posting a photo might help. Regards, Dazzlevision

28th Mar 2014, 12:27 am	#6
MALC SCOTT Octode Join Date: Aug 2006 Location: Willington, County Durham, UK. Posts: 1,499	Re: Weyrad coil Hi Ed, L207 was the 7.8khz ident coil on the Rediffusion MK1 decoder board. __________________ Malc Scott

28th Mar 2014, 9:21 pm	#7
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Weyrad coil Hi Malc, thanks for that, It was quite high inductance (4mH) and was wound inside a mini pot core so I was guessing it was quite low frequency. Ed