>   The crystal requires loading caps, just as it does in a radio.  These
> should be present on the board and specified in the circuit diagram.  I
> find it highly improbable that these would be absent in a production kit
> though if you were building from an article such an oversight could
> occur ...

Dr Clement sells a completed PIC TNC for about $90.  Or you can
purchased the preprogrammed PIC (which is what I'm doing here).  He
includes a schematic with the PIC.  When I look at it, it shows a
20Mhz crystal connected to pins 9 and 10.  To me, it just looks like
a crystal (a cap symbol with a box between the plates).  That may be
implying loading caps, but I may be too ignorant to know that.

> > The application is called a MIM Module.
>
>   Ringing isn't practical from here, and articles may be a bit tedious
> but which mag was it in?  If it was on a Web site, that would be more
> like it.  Web sites are easy to arrange, *plenty* of volunteer hosts
> (such as myself!) for Amateur Radio.

I didn't find it on a webpage, although it may be on one.  I'll see
if I can find one.

> Care to elaborate on a MIM module?  The concept of using a MCU for a TNC
> is certainly not new.

The PIC is programmed to accept RS232 data from a GPS.  The PIC will
then calculate the CRC and the proper tones to send it over a radio
at 1200 baud (the APRS standard).  Of course it will key the radio
first.  You run his software to configure to to send only the GPS
data you want, your callsign, and text.  Its pretty nifty, and small.

Lloyd