Can’t get 6600M to key KPA500

Carl N8VZ

I’ve connected my 6600M to the Elecraft KPA500 and KAT500, but the 6600M will not to key the Amp. I have the RCA TX1 from the 6600M connected to the KAT500, then the KAT500 PTT RLY connected to the KPA500 PA Key. I have a coax cable on ANT1 on the rig, and it is connected to the KPA500 RF Input. A coax is also connected from the KPA500 RF Out to the KAT500 XMTR. I also enabled TX1 In the rig’s menu, and disabled the 6600M’s ATU. When I press the tune button on the rig, I get 10w out of the rig, but the amp does not key. What could I be doing wrong? I had it working with my 6500 with the same wiring setup. Any and all advice appreciated!

dlwarnberg

In Radio Setup, TX.. is RCA TX1 Enabled (blue)?  Also is the KPA500 in Operation mode and not standby?

Rich McCabe

I would unplug it from the Flex and short the RCA connector pin to shield and see if you can hear the relay click. If it doesn't then you need to look at the relay and/or amp.

You can also put an ohm meter on the TX1 on the Flex to prove its working which it more than likely is.

Jim-KB1ZNV

I have the very same hookup with my KPA500/KAT500 with no problem so I think Rich's advice is a good first step.

Jim K4JAF

I like Jim, use the KPA500/KAT500 combination with no problems..  Make sure the amp is keyed by shorting the cable going to the amp.  If that works ok, then check the continuity on the cable from the TX1 to ensure it is shorted when the radio is keyed.

Craig_KØCF

The KPA500 has no relay -- T/R switching is by PIN diodes and is totally silent. You might try TX2 and see if that works, being sure to enable it in radio setup.

73,
Craig, KØCF

Rich McCabe

Is that the same for the "KAT500 PTT RLY" ?

Also curious to why the KAT is involved in the keying process?

Jim-KB1ZNV

The keying first goes thru the KAT500 PTT RLY from the transceiver and then to the KPA500 PA Key.

K3SF

rich

the kat500 checks swr and if higher than 1.8:1 will not key the amp
but will go thru a tune cycle if kat500 automode is enabled



Carl
first the obvious ...is the KAT500 powered on?...i know ..i know.

second are you seeing 10 watts on KAT500 power meter

third ..what is the kat500 reading for swr?



last resort
check kpa500 menu item

INHIB IN  should be set to  DISABLE


ENABLE allows the amplifier operation to be inhibited (won’t amplify) when a logic low is applied to pin 11 of the AUX Connector (see pg 17). When amplification is inhibited, an underscore instead of the asterisk appears on the left end of the LCD display.

Rich McCabe

Thanks Paul. Sounds obvious after you told me LOL

Carl N8VZ

Thanks.  That's a good idea.  I shorted the connection, and it did NOT put the KPA500 into TX.  Would seem to indicate to me that something is wrong in the KAT500.  I'm going to focus on that next.

Carl N8VZ

Yes, TX1 enabled and KPA500 in OPER mode.

Carl N8VZ

Thanks, see comments above.

Carl N8VZ

Same problem with TX2 and TX1.

Rich McCabe

Can you go direct to amp to rule out tuner for now?

Carl N8VZ

Thanks, everyone.  Problem now solved.  I apparently had corrupted firmware in the KAT500.  I was using the most recent version (1.75), but I forced a new install of the same version, and voila pressing Tune on the rig now keys the amp and it amplifies as per normal.  Rich's suggestion to unplug the Flex and see if shorting the connector pins would send the amp into TX was the key.  When it didn't produce TX, I started to focus on the KAT500, and that's where the problem was.  Not sure how I got the firmware in the KAT500 corrupted.  But, as they say, all's well that ends well!

革命 BU2AH

Carl, I have the same problem like yours of right now. could you please describe more detail regarding the process of you how to fix this issue. Such as, what kind of connector pins you did check or did you open it to check the PCB? or Coax cable changed? .... etc,

Carl N8VZ

BU2AH de N8VZ . . . Not at my QTH and won’t be for a week. Also, the amp is now back at the Elecraft factory for repair for other problems, including receive signal attenuation. My memory is that I had the amp connected using the wiring diagram in the KPA500 manual for non-Elecraft rigs. I connected the PTT line from the KAT500 to one of the 6600M’s alternate PTT RCA connectors. I don’t remember the exact abbreviation for that line. Perhaps someone else can help. But, as I said, the key was reloading the firmware on the KAT500. When I get back to the shack I’d be glad to help further if needed.

革命 BU2AH

Thanks. but how do you check the firmware number?
And how is the cable connection structure right now? Did you use  E850463 to link between KPA500 and KAT500? 

Jim K4JAF

See page 12 of the KPA500 manual for keying the amp individually or page 12 of the KAT500 manual for keying the amp and the tuner together.
I would try to use only the KPA500 initially and make sure it is keyed properly, then add the tuner to the setup.  
The first step is getting the KPA keyed and working properly, then adding the tuner in the line and working properly.  For basic operation, all you need is the keying line from the radio to tuner, and a keying line from the tuner to the amplifier. 
After all is being keyed properly, you can proceed to adding automatic tune by band or frequency if you so desire.

Carl N8VZ

You can tell the current firmware via the Elecraft KPA500 utility that you can download from the Elecraft web site. I’m my case, probably a rare problem, my firmware was corrupt. I did not install upgraded firmware. I just reinstalled the same version.

Carl N8VZ

Correction: My corrupted firmware was in the KAT500 not the KPA500.

革命 BU2AH

I solved the AMP TX issue, just built a cable, see the Owner's Manual page 27.
Thank you, Carl and everybody. Of cause, the Elecraft Gary helps me a lot.

Carl N8VZ

Glad you found the problem, BU2AH. Happy DXing.