[ICOM] IC 229H deviation adjustment?

[Jim Hargrave]

Paul,

I would first assume the radio deviation is correct.
I would suspect the TNC may be over or under driving the radio.

Since you do not have a service monitor or Deviation meter, I would suggest
you listen to your signal using another receiver.

Press a button on your Mic TTP and listen to the tone volume. Now place the
TNC/Radio in transmit and adjust the TNC audio output for the same relative
volume or slightly lower. This should place you in the ball park. You could
actually set the TNC output lower and it should work ok as long as you have
a good path to the Packet digi/cluster.

I ran a Packet BBS for many years and had ports on four bands. I adjusted
the radio deviation using a Heathkit IM-4180 deviation meter.
I set the voice deviation on the radio to 5KHZ and the TTP deviation to 3
kHz and then adjusted the TNC's to 2.5 KHZ. This proved to be a successful
setup. All my radios were ICOM except the one on 223.58 mhz.


    73s de Jim
       W5IFP




  > -----Original Message-----
  > From: icom-bounces at mailman.qth.net
  > [mailto:icom-bounces at mailman.qth.net]On Behalf Of Paul Erickson
  > Sent: Friday, July 15, 2011 11:26 AM
  > To: ICOM Reflector
  > Subject: [ICOM] IC 229H deviation adjustment?
  >
  >
  > Has anyone had any experience adjusting the deviation on the IC 229H?
  >
  > I have a copy of the service manual, and know that R12 on the
  > main board
  > is the
  > adjustment point, but I don't have a service monitor, and was wondering
  > if there
  > was some other way to assess the amount of adjustment needed? I
  > am trying to
  > use the rig for packet, and I suspect that the deviation is too wide to
  > allow me
  > to contact a local packet cluster, which I can hear fine, but
  > cannot seem to
  > connect to.
  >
  > Any thoughts would be greatly appreciated.
  >
  > cheers, Paul - VA7NT
  >
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