[GreenKeys] modern TU's comments

[Pete Lancashire]

> I'd say you are a glutton for punishment

Can't really disagree there. I also have a collection of 50's and 60's
test equipment. Although
very few tubes though. The SP-600/CV89 yea pretty crappy compared to today but
for me to have a corner of a room where stuff with glow-lamps exist is
just for memory
of a teen on HF. Kind of like my neighbor with his ground up restored
1968 Impala
talk about impractical :-)

-pete



On Sun, Aug 1, 2010 at 2:28 PM, Jim Haynes <jhhaynes at earthlink.net> wrote:
> I'd say you are a glutton for punishment if you are expecting to re-create
> an old RTTY station and actually use it.  My experience with SP-600
> receivers and their predecessors is that they are far too drifty for
> satisfactory RTTY work - especially using 170 Hz shift instead of 850.
> I suspect the reason 850 was originally chosen was that it allowed a
> lot of tolerance for transmitter and receiver drift.  When we started
> to get more stable gear, thanks to SSB, it became feasible to go to 170
> Hz shift.
>
> There is quite a bit of amateur 60 wpm RTTY left, but mainly for DX
> and contesting.  Not that I wouldn't enjoy a ragchew in that mode,
> but most all the ragchewers have gone to PSK31.
>
> The ST-8000 and Dovetron TUs are a lot better than the CV-89 ever was.
> In particular they include regenerative repeaters, which can protect
> against the loss of several characters in a row when a stop pulse
> gets mutilated.  I've been told but haven't verified it that the
> computer RTTY software MMTTY provides a cleaned-up output that can
> be used to drive a printer.  The CV-89 also has the reliability
> problem of all those hot tubes sealed up in a closed box.
>
> I'm glad you want to preserve a working mechanical TTY - those are dear
> to my heart as well - but for on-the-air operation I much prefer the
> modern stuff.
>
> Jim W6JVE
>