[MRCA] Mystery Project

[Nick England]

1. Converting EIA from your computer to teletype current loop (so I have
heard, no experience). Should also work for converting MIL +/-6v teletype
signals to current loop.

2. Building a replica of a PYTHON crypto machine
https://www.navy-radio.com/crypto/fgq1-1610-09.jpg
https://www.navy-radio.com/crypto/fgq1-1610-07.jpg



On Thu, May 25, 2023 at 9:38 AM Ray Fantini <RAFANTINI at salisbury.edu> wrote:

> Please enlighten as to the possible use of the polar relay beyond land
> line circuits? Cathode keying replaced mechanical devices in TU by the late
> forties and early fifties, not being contrary and know that the polar relay
> has been around for a long time but have no idea why it would be used or
> for what? My best assumption would be that they were used to allow week
> currents that were on land lines to key the high current loops on the
> teletype printers and allow the high current loops on keyboards and perf
> systems to produce low current for distribution over land lines?
>
>
>
> Ray F/KA3EKH
>
>
>
> *From:* mrca-bounces at mailman.qth.net <mrca-bounces at mailman.qth.net> *On
> Behalf Of *B. Smith
> *Sent:* Wednesday, May 24, 2023 11:00 PM
> *To:* mrca at mailman.qth.net
> *Subject:* Re: [MRCA] Mystery Project
>
>
>
>
>
> KM4V is correct and a tip of the Hatlo hat to him. The relay is adjusted
> for "Equal Time" on the pulses with equal time displayed as center on the
> meter. The relay has numerous adjustments and the alignment procedure is
> fairly complicated but most relays just need minor adjustment unless they
> have been Ham Hacked.   Polar Relays and their circuits are PFM.
>
> On 5/24/2023 3:58 PM, highpwr at bellsouth.net wrote:
>
> Polar relay test and alignment / RTTY testing.
>
>
>
> KM4V
>
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-- 
Nick England K4NYW
www.navy-radio.com
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