[GreenKeys] 75 baud RTTY

[Jim Haynes]

On Sat, 20 May 2023, Jeffrey Golas wrote:

> Just curious, since I dont think Ill have the UGC-48 done at the ship 
> for a while yet...has anyone done 75 baud RTTY over HF? Work ok? We do 
> have one working UGC-48 (28 dome top) geared for 75 baud (74.2? or 
> whatever the Navy used)
>
Back in the beginning of amateur RTTY we were required to use 45.45
baud (60 wpm) by the FCC.  When Model 28 equipment become more plentiful
some guys petitioned the FCC successfully to allow higher baud rates
so they could show off their 100 wpm machines.  This never gained much
popularity.

Then it turns out that because of the nature of the HF medium 45.45 baud
is about as fast as you want to go.  Higher speeds, shorter bits, are
much worse affected by things like multipath propagation.

Jim W6JVE