Working Packet Radio with a VT132 and a AEA PK-232

I’ve posted before about using a VT132 terminal board to control a PK-232 packet TNC. Here’s a few more specific steps and commands.

On first startup after doing the * auto-baud detection, the first thing you’ll see is the “cmd” prompt. If this is your first time setting up, or if the internal battery is low and it’s not preserving your settings since last time, the first thing you’ll want to do from the cmd: prompt is set your callsign (set your own callsign here):

MYcall was PK232
MYcall now KK6DCT

If you’re working VHF packet, turn on VHF mode, with:


If it was off, now it’s on.

Set baud to 1200 for VHF packet:

HB 1200

Now enter D to disconnect, and we’re ready to send some packets. To re-enter this command mode, press Ctrl C.

By default the PK232 has a MPROTO value of OFF which doesn’t display any received packets other than those sent to your callsign. Set MPROTO ON and you’ll display other packets heard.

Additionally, the default value of MON as 4 will show some but not all packets. Set MON 6 to display all packets decoded. If you’re hearing other packets but they’re still not being decoded, enter WHYNOT ON to get an explanation.

At this point you’re ready to go. C NODENAME to connect to a nearby node!

Sun Ultra 60 serial console login with a VT132

I recently assembled a VT132 and have been connecting it to various things to enjoy some serial terminal goodness.

I’ve tried a number of serial cables and serial terminal programs on my Atari ST to get a serial connection to my Sun Ultra 60 but never managed to get it to work. I didn’t know if this was due to my serial cable or something else. I bought and assembled the VT121 as a VT100 compatible serial terminal to have a better attempt at connecting to some of the devices I have around that support serial connections.

On the VT132 there are jumper pins to switch between a straight though connection or a crossover connection. Through trial and error I found I needed to put the jumpers on 1-3 and 2-4 for the cross over connection and this worked with the Sun Ultra.

I don’t have a pic of the pins in this configuration, this is the section in the docs, and here’s the pin layout next to the voltage regulator for reference (center of the photo):

Pins 1 2 3 4 are on the right. Here’s the pins in the straight through config 1-2 and 3-4, the two jumpers on the right need to be switched to the other 1-3 and 2-4 configuration to work with the Sun Ultra:

There’s two serial connectors on the Sun Ultra 60, note that the DB25 at the top is a parallel connector. Serial A and B are beneath the keyboard connector:

Here’s some useful info on configuring Serial console connections to Sun hardware here. Typically on Sun Sparc systems, if you disconnect the keyboard and have a terminal connected to Serial A when you boot, the boot messages are redirected to the serial terminal instead of the video output. This is useful if you need to run diags on a machine, but it’s also fun to boot the machine up and logon from a serial console. Here’s what the console boot messages look like on my Ultra 60:

At this point I could successfully logon via the console. As I was looking into getting this working I took some notes as I was working on this. I’ll include them here for future reference in case they’re useful.

Other useful notes:

/etc/remote has section for enabling hardwire tip via /dev/term/a|b

See also here talks about /etc/ttytab to enable logins

To enable a logon prompt via Serial A or B after booting, and with keyboard connected:

From here:

sacadm -a -p mbmon -t ttymon -c /usr/lib/saf/ttymon -v `ttyadm -V` -y "TTY Ports a & b"

cat /dev/term/a shows keyboard entry from my VT132 terminal when I press enter, so I know input is reaching the port.

With my serial cable, I needed to set the straight through vs crossover jumpers on the VT132 to the crossover position get any output to appear on the terminal.

Set terminal to 9600 8N1.l

Using a VT132 for Packet Radio

I have an AEA PK-232 that I picked up a couple of years ago at my Amateur Radio club’s White Elephant sale for a few bucks. With the VT132 that I just recently built, it works as an excellent terminal client to the PK-232.

To connect, set baud rate in the VT132 to 1200 8N1. Connect with a null modem cable. Power on the PK-232 and you should see:

Press type a star (*) for auto-baud routine.

Press * and then you should see the AEA PK-232 startup copyright message.

To get a cmd: prompt to enter commands, press Ctrl-C.

I’ve attached my 2m radio with the audio in so far, and here’s a pic while decoding some APRS messages:

Next I need to make a custom cable to connect to my Icom’s data port, and then I should be all set to work some packet.

VT132 assembly: USB add on board notes

There’s no explicit instructions on the VT132 website for how to attach the optional USB addon board instead of the default PS/2 connector but there is an extremely details step by step video here.

Summarizing the additional steps:

  • trim the 4 back legs of the USB connector so that it sits flush to the red addon board and make sure the pins don’t protrude from the board, then solder the back pins to the add on board and make sure the soldering is flush so it will sit flush to the main board
  • solder the 2 larger outer pins from the back first, then the inside 2 pins
  • the addon board attaches to the main board component side up
  • push the black spacer of the 6 pin header all the way down so the spacer is flush to the end of the pins
  • attach the row of header pins though the top of addon baord to the back; there shouldn’t be any length of the header pins extending on the top
  • solder the header pins on the back of the addon board
  • put a small strip of electrical tape across the bottom side of the addon board before inserting to main board before soldering, to avoid any contact with the original PS/2 connector pads on the circuit board
  • insert the addon board, turn over and solder the pins
  • solder the two front structural legs on the usb connector