[Elecraft] Made a DB15 cable to connect K3 + KAT500, but now Amp is disabled

[Dick Dievendorff]

The amplifier key interrupt relay in the KAT500 has two separate poles. One
pole switches the RCA connector path, the other pole switches the path
between pin 10 of each of the two 15-pin accessory connectors.  

There is no connectivity between the two poles.  Thus, you cannot use one
RCA cable and one 15-pin cable.  

If you want to avoid the RCA cables, you'll need to use pin 10 of the 15-pin
accessory cable for both K3 to KAT500 and KAT500 to your SB-220. 

73 de Dick, K6KR


-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of zl2ke
Sent: Thursday, August 29, 2013 2:26 AM
To: elecraft at mailman.qth.net
Subject: [Elecraft] Made a DB15 cable to connect K3 + KAT500, but now Amp is
disabled

I had to make a DB15 cable since my K3 is side-by-side to the KAT500, so the
Elecraft cable that I ordered is too short (the DB15-Y cable is the only one
available and it is for a K3 on top of a KAT500).

However now my SB-220 Amplifier is no longer activated and does not 'fire
up' when the K3 transmits. All was OK before I connected the cable that I
made today, that is, the K3 and KAT500 did trip the linear amp's relay.

The cable that I made today does connect the K3 and KAT500 properly, so that
when I change bands on the K3 the KAT500 changes bands (and remembers the
correct setting for each band so that no tuning is needed).

Page 9 of the KAT500 manual shows the 10 Connector Pins to be used (leaving
5 pins unused),
however I did not connect Pin #15 because the notation states "ALC (Not
normally used...).
This means that I have made a cable of 9 wires.

It is my understanding that pin #10 is the Key LIne from the K3, which
should trigger the relay in my SB220 amp (via the KAT500).

There is an RCA-RCA cable from the K3's Key Out to the KAT500, and another
RCA-RCA cable from the SB220 to the KAT500.
This is the same configuration that I had prior to the new cable that I made
today, and as I have said, the SB220 did fire up OK when the K3 transmitted.

I took care in making and testing the cable, so I am sure of the continuity
of each wire.

There must be something that I have not done. 
How can I get my K3 to once again trigger the SB220 amp?

Thanks,  Steve  ZL2KE



--
View this message in context:
http://elecraft.365791.n2.nabble.com/Made-a-DB15-cable-to-connect-K3-KAT500-
but-now-Amp-is-disabled-tp7578367.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html