[RTTY] FW: Slightly off topic, history of 850 Hz shift?

[Dick Kriss]

The following is posting for Chris, N3JLY, who is not on the RTTY-Contesting
reflector. If you respond, please copy Chris Smolinski
<csmolinski at blackcatsystems.com>

Dick AA5VU

------ Forwarded Message
From: Chris Smolinski <csmolinski at blackcatsystems.com>
Date: Thu, 28 Sep 2006 11:29:19 -0400

Hi Dick,

Sure, please go ahead and post it, thanks!  I'm sure someone out
there knows the history. I am curious if the shifts commonly used are
based on some engineering/technical reasons, or if they were
arbitrarily chosen.

>
>On 9/28/06 8:45 AM, "Chris Smolinski" <csmolinski at blackcatsystems.com>
>wrote:
>
>>  Someone asked me why much of the military RTTY on HF commonly uses
>>  850 Hz shift. I am curious if anyone knows the history behind the
>>  selection of this shift rate, or if it was just arbitrary.
>>
>
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