[GreenKeys] Diddle, Real Metal, & Indeterminate Line Length

[George B. Hutchison]

GreenKeyers - - -

I am no math expert in these matters, but I do bel;ieve communications
theory states that a circuit tends to be more reliable if some manner of
signal transmission is continuously present on the circuit.

Diddle accomplishes this. In the days of slideback detectors (Bob
Weitbrecht, W6NRM,) and ATC/DTC contention (Irv, W6FFC) diddle did a
nice job of keeping the circuitry's determination of mark and space
right around the zero crossing point. It irritated the hell outa me when
Larry, WA6JYJ (now W7JYJ) first started using it, but, it made things
better.

The downside of running diddle is that if one is running a reperf, you
can chug out miles of tape with nothing but LTRS on it. Brian Beezley's
RITTY program has an RS-232 output that has a "Diddle Filter" on it, in
that after two or three LTRS characters it shuts off output and goes
idle until a character other than LTRS comes across the circuit. Saves
lotsa tape.

RITTY is still available from Brian, he just does not publicize it at
all. If you are interested, e-mail me and I will make arrangements for
you to contact him. RITTY is a DOS-based program that uses some very
sophisticated DSP algorithms. A dirt-bag DX-66 computer with RITTY is a
push for an ST-8000 or Universal 8000 when it comes to digging down into
the mud. Cost is 100 dollars, and each copy is personalized with your
name and call.

Indeterminate line length is caused by the RTTY software geeks relying
on word wrap to determine the end of line point, rather than calling a
specific point (usually 68 to 72 characters) as the machines are
designed to run at.

Auto Cr-Lf  and non-overline is nice, but, for those who like to see the
really intricate overstrike TTY art, both will tend to turn a piece of
artwork into a piece of crap.

Nowadays, when most on-air RTTY communications consist of CQs and Signal
Strength reports, maybe a defined EOL point is superfluous, because the
lines never get that long. I prefer DEFINED EOL-CR points. It's just
more professional, and the machines LIKE THEM. BLACK SPOTS on the right
hand side are very hard to read.

If your software has a means of setting the EOL-CR, it is best to use
it.

Regarding a RATTS net, or autostart net, I am all for it. I am close to
getting back on the air, and it would be nice to have something like
that going.

The RATTS net here in the Northwest is one of the longest surviving nets
of its type. They seldom handle any traffic, but by golly, the means and
the good-will is there.

Two or three years ago I participated in an Emergency Communications
Exercise wherein the Red Cross was to be the central focus of the
operation. The Red Cross did not know sawdust from Arbuckle's Coffee, in
that they did not seem to know they were a part of it.

I turned off my transmitter in disgust. The RATTS guys tried.

W7TTY will be back on the air soon.

Stay Tuned, film at eleven...

73,

George - W7TTY