[GreenKeys] WTD Teletype 403103 EIA to 60ma loop interface

Nick England nick at navy-radio.com
Sat Jan 24 14:13:36 EST 2026


Does anyone have one of these little black boxes with a built-in loop supply?
Or a copy of Specification 50998S or the applicable Schematic Diagram (WD)?

Cheers,
Nick England K4NYW
www.navy-radio.com
Nick England K4NYW
Chapel Hill NC
www.navy-radio.com


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