[Elecraft] Distinguishing KIO3 Pullups?

[Don Wilhelm]

Rick,

Certainly there is an easy way.

Remove the ACC connector and measure the DC voltages with your DMM at 
the pins for the Band Data.
Refer to the chart on page 19 of the manual.
Select 12 meters, or 10 meters or 6 meters and the BAND 3 output should 
read 5 volts if the pullup resistors are installed.
Similarly, select 17 meters and the BAND 2, BAND 1 and BAND 0 pins 
should read 5 volts if the pullup resistors are installed.
If you find zero volts (or a low voltage) reading in the above tests, 
the pullup resistors are not installed.

Given your problem statement (relays not being pulled in), I suspect 
your problem is not with pullup resistors, but something else associated 
with your band decoder.  The band data voltages should not be used to 
source current in order to pull in relays.  Some intermittent decoder 
and relay driver circuits should be in place - the relay drivers in your 
decoder box should be doing the work of pulling in the relays.
If you have problems with insufficient voltage for pulling in the 
relays, look in your decoder box for the problem.

73,
Don W3FPR

On 9/10/2015 6:14 PM, Rick Tavan N6XI wrote:
> Is there an easy way to determine whether a KIO3 is a B model with pullup
> resistors on the band data lines without pulling the rig and opening it up?
>
> Since a recent change in band decoders, I've been troubled by
> intermittently insufficient voltage to pull in my antenna relays and I'm
> wondering if perhaps it originates with band data not being pulled up.
>
> Thanks & 73,
>
> /Rick
>