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Need help finding specs for old Calectro audio transformer

sunbonnet55

Jun 7, 2022
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Does anyone out there have an old Calectro catalog that has the specs to a D1-711 audio transformer? It's got a center-tapped primary and single secondary.

Thanks,

Steve M.
 

Audioguru

Sep 24, 2016
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What are you making that needs an old audio transformer? An antique vacuum tubes amplifier?
 

Audioguru

Sep 24, 2016
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A newer solid state amplifier might have used your old transformer 67 years ago:
 

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sunbonnet55

Jun 7, 2022
3
Joined
Jun 7, 2022
Messages
3
What are you making that needs an old audio transformer? An antique vacuum tubes amplifier?

It's from an old 20 meter homebrew receiver that I'm repairing. The Calectro D1-711 is what is installed on the board, It's the output transformer of a single balanced direct conversion mixer. I finally pulled to the transformer off the board and measured its parameters with an LCR meter. At 1 kHz, looks like 3 KΩ primary (left coil) and 15KΩ secondary. The circuit is from the April 1978 issue of QST.
W1VD_20m_DC_RX.JPG
 
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