[aprssig] Icom 2820 Din to KPC3 connection?

Stephen H. Smith wa8lmf2 at aol.com
Fri May 10 17:14:33 EDT 2013

On 5/10/2013 12:24 PM, Robert Bruninga wrote:
> For Scout Jamboree I’m having to wire a KPC3 TNC to an ICOM 2820 in the blind.
> I wont get to see the radio but briefly and have to have it working but have
> zero experience with the radio.  Never seen one…
> I assume it is as simple as wiring the correct pins on the mini-DIN connector
> to the proper DB9 radio connector on the TNC and just tuning the radio to 144.39?

Uh No....

1)   You are going to have to fiddle with the TX deviation after you connect 
the two.

2)   Since the radio is a dual-bander, you will have to deal with getting the 
mini-DIN data port switched to the correct side of the radio, and then ensure 
it stays on that side.  There is a typically-clumsy multi-step menu option to 
to do this.  From Page 122 of the manual:

Packet operation band selection
Both bands, or either the left or right band only, can be specified for packet 
operation to suit your preference.
qPush [F•]to display function guide.
wPush [MENU](V/MHz•SCAN)(Right band’s)to enter MENU
eRotate  [DIAL] to select “PACKET” then push
rRotate [DIAL] to select “PACKET BAND” then push
tRotate [DIAL]to select desired band from MAIN (default),
left (L) and right (R), then push [MAIN•BAND].
•MAIN : The main band is used for packet operation.
•Left (L)/Right (r) : The selected left or right band can only
be used for packet operation.
yPush [BACK](V/MHz•SCAN)(Right band’s) twice to return
to frequency indication

3)   Manual warns to set TNC TXD to 50-100 milliseconds (!).

Full details on the pinout of the 6-pin mini-DIN data connector here on my website:




Stephen H. Smith    wa8lmf (at) aol.com
Skype:        WA8LMF
Home Page:          http://wa8lmf.net

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