[Elecraft] Killed the KPA500 :)

[Luis V. Romero]

Michael:

The KPA500 defaults to power up in STANDBY but is programmable to power up
in OPERATE mode. Someone must have changed yours.

The KPA500 can also be programmed to switch to standby on band changes. It
defaults to selecting STANDBY or OPERATE per the last band change.

When connected to a K3 using the KPAUX cables, the amplifier and the radio
communicate and the radio will reduce power when you switch the amp to
OPERATE.

I run mine in Power up: STANDBY, Band change: Switch to STANDBY.  Its harder
to do stupid things in this configuration. I'd rather accidentally transmit
at 100w than blow the amp up. Also, my KAT500 tuner can auto bypass the amp
if the SWR reaches 2.5:1 threshold to protect the amp. This is also
programmable.

The menu settings for all of this are in the KPA500 Operations Manual on
page 19.  BTW, there is no T/R relay to click in the amp. It uses PIN Diode
T/R switching.  When you key the amp, and if you have it connected to the
same PTT as the radio, you should see an asterisk (*) in the LCD window that
tells you the amp is "keyed".

You may have blown up the input attenuator. Or the RF deck. Or both. As a
machine I used to work with said when its power supply was overheating: "$$$
UP IN SMOKE!".

73

Lu Romero - W4LT




From: Michael Walker <va3mw at portcredit.net>
To: Andy Durbin <a.durbin at msn.com>
Cc: "Elecraft at mailman.qth.net" <elecraft at mailman.qth.net>
Subject: Re: [Elecraft] Killed the KPA500 :)
Message-ID:
	<CA+33ts5vyMXY7o1vHi=8HoNaX4cKLsKhHfYR8te4-qYf8SeBqw at mail.gmail.com>
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I have the schematics, as someone was kind enough to send them to me.

Yes, I forgot the KPA500 powers up in Operate.  It is the only Amp I own
that does this.

I will mention it to Elecraft when I chat with them later today and suggest
the default should be the other way around.

Mike va3mw