[GreenKeys] Re: Just a few RTTY basic questions and a holidaythanks to all

[Ralph Mowery]

----- Original Message ----- 
From: <Wndrrt at cs.com>
To: <greenkeys at mailman.qth.net>
Sent: Thursday, November 25, 2004 8:49 PM
Subject: [GreenKeys] Re: Just a few RTTY basic questions and a holidaythanks
to all


> Hello all and a Happy Thanksgiving.
>
> Jan Bogue KD6EMW here with a short update on the 19 set.  I did win the
bid
> on a 1962 RTTY Hand Book on ebay.  Other information is being sent to me
at
> this time.  Last week, I hooked up my temporary loop supply to the receive
loop,
> and as I tapped the alligator clip on the positive contact screw on the
> terminal strip, the keys started hitting the platen in random order, so
looks like
> my selector magnet works as well as the printer mechanisms.  This week I
am
> going to try and trace out the send loop through the keyboard and the TD.
>
> A few questions:
>
> If my machine is geared for 60 wpm and 45.45 baud, what happens if the 19
> tries to copy 50 baud on Hamburg Metro Weather (taken from rtty.com
frequency
> list)?
>
> Can the 19 be geared to handle short 75 baud contacts?
>
> It looks like the 19 is limited to copying Amateur Bulletins on 3620
W2QFR.
> Are there other frequencies where the baud is a civilized 45.45 for the
old
> machines to work on?
>
> Do some computer programs and modern, painfully quiet, RTTY setups without
> moving machine parts equipped to communicate with the old machines?  New
on one
> end of the QSO and antique on the other end?
>
> All basic stuff, but when you are in first grade you have to start at the
> bottom with the basics.
>
> And now for a quick Thanksgiving note:
>
> I have only been a Ham for three months, and when I think back I cannot
> remember a time when I have come in contact with  so many helpful and kind
people
> in such a short period of time. This includes those in related fields as
well.
> And the attitude is contageous.  I find myself passing the attitude on in
my
> daily dealings with others at my job.  Thanks to all.
>
> Two more questions:
>
> Are the old machines limited to talking only to their own generation?
>
> Can my Hallicrafters Model SX99 or my Hallicrafters Sky Champion be used
as a
> source for a RTTY signal?  Dose the signal have to come from a SSB  lower
> band radio?
>
> Thanks for your help
> Jan Bogue KD6EMW

Most ham transmissions are at 60 wpm.  There are some random contacts on the
low bands and you can count on W1AW bulitens .  To find the times and
frequencies go to www.arrl.org  .

As long as the baud rate is the same it makes no differance if a computer
and sound card is used or if some of the oldest mechanical equipment and a
simple one tube demodulater is used.  The only thing is the
converter/demodulator will give beter copy  off the air as the design and
filters are improved.  This is for sound card programs and computers and
also for the mechanical designs.  If you are on the receiving end it will
sound the same nomater what is being used.  The computers will normally have
some buffering built in so that if you can type greater than 60 wpm the
typing will be continious.  Typing off the machanical keyboard will be
limiated to 60 wpm with no buffering and usually more jerkey.  The 19 table
setup can be made to do this by pressing the switch so that you are punching
tape and sending that to the TD unit and letting that key the loop.  That is
why the TD is just to the left of the keyboard.  You just can not see what
you are typing tuil it is printed at a later time.

The signal does not have to come from a ssb receiver.  For most people that
is the best way.  There have been some converters that convert directly from
the IF frequency of a receiver.  We had a repeater on the 220 mhz band that
was FM and using audio tones.  It is the legal requirements for hams that
make the low bands (below 30 mhz)  use the FSK that is normally received by
a ssb receiver.  It may confuse you , but you can use lsb and set the
demodulator to "nornal" or you can use usb and set it to "reverse".

To transmitt you can feed audio tones into a ssb transmitter and it will
come out as FSK if pure sine waves are used.  You can also use a CW
transmitter and shift the carrier (used to be done with a diode and
capacitor circuit on the oscillator).  The resuslts on the receiving end
will be the same.

73 de KU4PT