IC 2500A Cross Band Repeater Setup
In this example, we will make a 23 cm repeater accessible to users
with 70 cm handhelds. We will control the link with CTCSS tones.
Our repeater output frequency is 12xx.xx MHz (-20 MHz offset), and our
link frequency will be 44x.xxx MHz. We'll use the tone 91.5 Hz for
access control.
The handheld user, then, would select 44x.xxx simplex, and transmit a
91.5 Hz tone for access. This user should key up, wait 2 seconds, then
begin speaking, to give both repeaters a chance to warm up.
Setting up the IC-2500A:
- Put both bands in VFO mode.
- Set up the output band with repeater frequency (12xx.xx MHz),
offset and tone (if needed) as listed in the repeater guide or given
by the repeater operator.
- Set other band for simplex, 44x.xxx MHz with 91.5 Hz tone squelch.
- Give the squelch a little space. A hairline squelch will QRM the
repeater input (and the output. and a whole bunch of repeater users.)
- Turn off radio.
- With the power off, push and hold following buttons:
MONI, CALL, SET, and DOWN button on microphone
while holding all above, turn on power.
Restoring normal operation:
- With power on, hold SET button and hit CALL button
Troubleshooting:
- Try resetting the CPU: Power off; hold the MONI and MW buttons;
power on. (Yes, this erases memory!)
- Remove diode D9 from the logic board. The logic board is the
small board right behind the front panel display. This is not for the
weak at heart. Remove the large tuning knob, and the sleeve ring
around the microphone jack. Remove the top and bottom covers, and then
remove the 4 screws holding the front panel in place.
Then remove 5 screws securing the display/logic board to the chassis.
Be careful about some grounding straps around the edge of this board;
you'll be loosening them, too. Carefully pull the board away from the
chassis and see the row of diodes just about in line with the main volume
knob. D9 (if it's there to begin with) is the second from the bottom
of that row. Carefully clip the lead. Even more carefully reverse
your disassembly. Secure the logic board, replace the display cover,
and its screws, then the top and bottom covers and their screws.
Replace the microphone sleeve ring and the main tuning knob and you're
done. Newer units didn't have this diode to begin with, but mine did.
My serial number is 01155.
Legal notes:
- Crossbanding someone else's repeater is considered poor form.
Cross banding your own is ok. Getting permission is a fine idea.
- Your link station must ID, too! Of course, if the link and
the repeater have the same call signs, you're probably, OK. Otherwise
you'll need an external keyer. (But note that the PTT line on the
radio is disabled when in crossband mode! Oops! Looks like you'll
need to hook that keyer to another transmitter...)
- As always, use minimum power.