[Elecraft] :( Please help with KAT1 debug

[Rod N0RC]

Matthew,

I had the same symptoms with a recently built KAT1 ATU. The problem
was the an unprogrammed control chip U1. You may have the same
problem, best bet contact Elecraft. There was small number of KAT1 ATU
U1s unprogrammed.

That said, FWIW, if you want to do more trouble shooting here is what
I did:


1) Visual inspection of circuit board, no solder bridges, misplaced
parts or unsoldered pads found. Re-inspect for same with fresh eyes
the next day.

2) No folded/disconnected pins on U1, I inspected carefully for that,
and on P1 & P2.

3) Main CPU is REV 109E, required for KAT1

4) reflowed all solder connections on U1 socket

5) Voltage checks:

    U1 Pin  1: 6   VDC
    U1 Pin 20: 6   VDC
    U1 Pin 28: 5.5 VDC

measurements taken from IC pins direct, so connectors and sockets
are OK.

6) I tried measuring the frequency of the Ceramic Resonator at pins 9
& 10 with a RS Freq. meter. Nothing, but I think the signal level is
quite low. I tried a little pick up loop connected to my Icom 746,
nothing heard. I tried the same methods with the Resonator on the band
module, similar results. I didn't have access to better metrology to
evaluate the resonator.

7) Removed and reinstalled U1, hoping to correct dirty pin/socket
problem if it existed, no luck.

8) Contacted Elecraft. ;-)

73,  Rod N0RC



----- Original Message -----
From: "Matthew Marx" <matthew_marx@msn.com>
To: <elecraft@mailman.qth.net>
Sent: Wednesday, June 12, 2002 6:21 AM
Subject: [Elecraft] :( Please help with KAT1 debug


...
> Last night I tried installing the ATU and got the dreaded "three
dash"
> message in the ATU menu setting.  I've got ATU board C, and RF board
E, so
> installing the ATU involved changing the P3 jumper on the RF board
and