[Elecraft] Interfacing TS480 to KPA500

[Jack Brindle]

Mike;

First, the KPA serial ports are _not_ pass-through. Each has a specific purpose and don’t actually work together.

How you set up the XCVR serial port connection depends entirely on whether there is a computer in the 
situation or not, and whether that computer polls the radio for information. Since this is a remote base, can we
assume that a computer is involved and it is getting info from the radio? If so, then you need to set up the 
KPA500 so that it simply eavesdrops on the conversation. You will need to fabricate a Y adapter for this. In 
the case of the KPA all signals can go through, but realistically you only need pins 2, 3, 5 and (I believe) 8 
connected. Pin 8 is the handshake pin for the TS480, and is needed to allow the radio to send data on the
RS-232 port. It does not need to be connected to the KPA500 port, but if it is the KPA will simply ignore it.
Note that the KPA does not make a connection to that pin, so if you set the station up without a computer,
you will need to provide +12V for that signal to allow the TS480 to talk.

As the manual indicates on page 12, there are three menu items involved with this situation. You will
need to set the RADIO item to SERIAL, then set the RS232 X item to the appropriate data rate. Finally,
since the computer is polling the radio for data, set SER POLL to OFF. If there is nothing doing the polling,
you will need to set this item to ON to allow the KPA to do this task.

With this setup, things should work just fine. But we aren’t finished, you did mention a KRC2, so let’s discuss that.

I would suggest inserting the KRC2 in between the TS-480 and the KPA500. Make sure that only pins 2, 3 and 5
go to the KRC2 ports. That pesky TS480 handshake signal should not go through the KRC2 without making
changes inside the KRC2. What changes? Disconnect the W jumpers for the handshake pins and then jumper
across the connector side of the pins so that the signal gets passed from one DE9 to the other. Then set the
serial port data rate jumpers for the appropriate rate. The KRC2 can do 4800, 9600 and 19200 bps with the V1.6
firmware. You probably want to run as fast as you can on the serial port, which means 19200 bps.
You can then plug the serial port cables into their appropriate connectors and try things out.

Be sure to check to make sure that pin 8 is the handshake pin needed for the TS480. I think it is that pin, but
will need to check it. Also look at the KRC2 manual for the proper W jumpers. I’ll also take a look and privately
email you what I come up with.

Your station should work quite well in this configuration. Good luck!

73,

Jack Brindle, W6FB
Elecraft Engineering


On May 22, 2014, at 7:38 AM, Michael Walker <va3mw at portcredit.net> wrote:

> All
> 
> My remote base runs on a TS480 and I will be adding a KPA500 to the mix.
> 
> In going over the documentation, I find that there is very little detail on
> actually interfacing on the RS232 port.  From what little I can read, I see
> it is as simple as plug it in and go, or am I missing something in the
> configuration.
> 
> Can I pass RS232 signal through the Amp or is it a passive listener and
> handles band changes.
> 
> I will also be using a KRC2 to change filters and antennas in the same
> solution.
> 
> Mike va3mw
> ______________________________________________________________
> 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
> Message delivered to jackbrindle at me.com