Satgen 54    Welcome to 9600 bps     10th April 90 by GM4IHJ
EXTRA.STOP PRESS.Good screen copy 9600 packet from callsign UOSAT3-1
1150ut 9 Apr .Uosat3 Oscar 14 is regularly transmiting 9600 bps FSK on
435.070 MHz. This transmission presents several features not met before.

The transmission is not always on 9600 bps. Uosat 3 mostly sends 1200 bps
signal ( not packet format ). When 9600 is on , it has usually sent for
1.5 minutes in every 6 minutes (but today 9th was sending continuous 9600
screen readable packet). With the receiver set to FM, the 9600 signal
sounds like noise. There is no tuning note , and newcomers can be forgiven
for assuming that no signal is present. But tune your receiver across the
signal and you will hear a change as you go from off tune noise ,onto the
noisy signal. To get properly on tune a centre tuning FM meter is
essential. Modern transceivers and receivers let you to switch between
centre tuning and signal strength, and you will need to do this because
signal strength is the only guide you have to tell you when your aerial
tracking is optimised. Tuning is much less critical than with BPSK packet.
You can tune in 1Khz or 5Khz steps. AFC would be nice , but few receiver
presently feature this aid. I use scope eye diagram as tracking aid

Uosat 3's signal is the strongest/steadiest of all the packet satellites.
I take signal from the ICOM 451 ( pin 9 IC7 Rx discriminator), and feed it
direct to the G3RUH 9600 FSK modem ( note not the fuji modem ). At TP4 on
the modem I see the signal waveform but when these  transmissions are BERT
Bit Error Rate Tests, the TP6 output of the modem Rx Data out, shows a DC
level consequent on the test transmission being a succession of 1's.
 
The RUH modem Rx data goes to a modified TNC 320 ( with its own modem
disconnected). All you see on the TNC is a steady DCD LED light when
signal is present. You get screen print with packet,not with BERT. One
warning. You must reset the Baud command on your TNC before you start.Some
TNCs use manual shift others use software, Which ever yours is , your
Receive baud rate must be 9600 . You can if you wish set the Terminal rate
to 9600, and set your computer software to 9600 if permissable. BUT you
must remember that your Terminal and your computer must be the same baud
rate, or they will not communicate one to the other.Remember to reset to
1200 baud when you go back to using the Fuji modem on 1200 BPSK.  You will
soon get fed up with all this plugging and unplugging, baud setting and
resetting.

The Uosat 3 9600 FSK system looks like the one for me. Given the  NK6K and
G0/K8KA software, it should have few of the problems of FO-20.

FO-20 mode JD has not had its bulletin board on for over a week now. It
does operate as a digipeater on some days. Pacsat is uploading software
and telemetry will shortly go to binary. 73 de John GM4IHJ@GB7MAC