Amateur Radio use of Teleprinters (was Re: New batch of pdp8 OMNIBUS to USB interface! Please Read and react!)

Eric Smith spacewar at
Thu Feb 16 02:30:26 CST 2017

On Wed, Feb 15, 2017 at 11:29 PM, Tony Duell <ard.p850ug1 at> wrote:

> I think at one time radio amateurs (at least over here) had to use 5 bit
> ITA2
> machines for RTTY.

Same here.

> It may even be to this day that RTTY implies that, and
> that ASCII is classed as 'data'.

The FCC order authorizing Amateur Radio use of ASCII went into effect in
March of 1980, but at the moment I can't track down a copy of the actual
order.  The current FCC regs (§97.309) are more recent, and lump RTTY and
"data emission" together, allowing ITA2, AMTOR, or ASCII, or, with
additional limitations, "an unspecified digital code".  I suppose I could
use EBCDIC, FIELDATA, or the IBM Stretch character code, as long as I
didn't use it for the purpose of obscuring the meaning of the
communications, or to communicate with a station in a country with which
the US doesn't have an agreement allowing those codes to be used.

But the 5 level machines that were used over
> here tend to be Creeds (Creed 7s, 75s and 444s mostly).

I'm told that Teletype models 15, 19, and 28 were very common here. I've
mostly seen models 15 and 28. I've only once seen a mdoel 32 (ITA2
five-level version of model 33).

I've seen some Kleinschmidt teleprinters, but I've never seen a Creed.

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