(IC-970) IC-970 with 9600 Baud
To use the ICOM IC-970 on the UOSAT's (9600 baud), I made the following modifications:
Solder a shielded wire (I used RG174) to the anode of D16 (1SV50E). This is at the junction of R52 (470K) and C44 (.0047).
Make sure to solder the shield to the adjacent PC board ground plane.
Solder a shielded wire to pin 9 of IC11 (MC3357P), again make sure to solder the shield to the PC board ground plane.
Both transmit and receive are on the main unit circuit board. Make sure that you use IC11 as this is the sub band receiver. If you
plan to use the IC-970 for terrestrial packet (ie. simplex on either 145 or 440) you will need to add another shielded wire to IC5,
which is the main receiver discriminator.
I then brought the shielded wires out the rear of the radio.
I did this by removing the plate which covers the two holes located below ACC(1). In order to disconnect the wires from the
modem, I installed two phono jacks in the center of the holes on the metal plate. I have used this setup with the G3RUH modem,
PacComm NB96, and the MFJ-9600.
I found that it was not necessary to add the 10K series resistor to the transmit audio/deviation line. On all three, with the center
of the 10K pot range as 12 o'clock, I found that about 1 o'clock to work best on for me.
Make sure that the DC power source for the TNC and 9600 baud modem are on a clean supply (no ripple). Several users have
found this to be the reason they could not get their modems to work. Also make sure that the TNC modem switch is set to 9600
baud as this provides the 153.6kHz to the modem. The modem documentation is not very clear in this area. I run the terminal
speed at 19,200.
If you have any questions, I can be reached at:
Dale Hagert NM0H
3881 Serpentine Circle
Eagan, MN 55122
On Ubuntu/Debian command line or terminal, as root or superuser:
1. apt-get remove brltty
2. mknod /dev/ttyUSB0 c 188 0
3. chown -hR root:dialout /dev/ttyUSB0
4. chmod 0666 /dev/ttyUSB0
5. ls -l /dev/ttyUSB0
output should read similar to this:
crw-rw-rw- 1 root dialout 188, 0 2008-04-21 19:51 /dev/ttyUSB0
6. REBOOT. None of my applications would acknowledge the CI-V device's connection until after reboot, for whatever reason.
Repeat the above process if you have other serial-to-usb adapters that compete on your system.
7. If your application normally reads the device from /dev/ttyS0 ... back up your app's configuration and then try /dev/ttyUSB0 instead.
Promptly after reboot, linux programs like gMFSK, sgcontrol and other hamlib-dependent applications were able to read the frequency output of my ICOM R-75, with the Blackcat CI-V interface. I have "limited" control over the R-75 with Smart Gnome Control, but this seems to be a limitation of hamlib0, as this was also 'hit-and-miss' on my standard rs-232 cable, with Icom Control software.
Glenn Lyons VK4PK
Ver:gnl20182018 - pre published v0.9