[Elecraft] Questions from a Possible Builder/Owner

[Donald Nesbitt]

Hi Jim,

> 1.  How does the K2/100 key an RF amplifier (AL-811)?
> I have a Heil footswitch with a second cable for
> amplifier keying.  But, would prefer to use keying
> from the rig itself.

The KPA100 has a built-in solid state keying circuit for positively keyed
amplifiers (like your AL-811).  There is an RCA jack on the back of the
KPA100 and you simply connect an RCA male cable from it to the Relay jack on
the AL-811.  There is no need for a second cable.

> 2.  How is ALC sent from my RF amplifier back to the
> K2/100?  I've reviewed the K2/100 manuals and cannot
> find how it is done.  Maybe it really isn't needed.

The K2/100 does not have any provision for ALC input from an external
source.  ALC from the AL-811 amplifier back to the K2 is not necessary.
Since ALC from an external amplifier is generated "after the fact" it does
little to control the generation of distortion products that result from the
amplifier being overdrive.  In most amateur amplifiers, in order for an ALC
voltage to be generated , the amp must be overdriven in the first place!
Obviously this is not good!  Of couse, the power control on the K2/100 can
always be set to a level such that various amplifiers are not overdriven.

> 3.  How do I adapt my Heil Headset Pro and Goldline
> microphones.  They currently are used with an
> IC-746pro by using a Heil adapter cable.  They now go
> thru a homebrew switchbox with the adapter cable
> between the rig and switchbox.

The microphone input circuit in the K2 has provisions on a jumper block to
route functions to various pins according to which microphone you wish to
use.  These options are explained and individual choices are made during
construction of the K2.  I am not familier with the requirements of the Heil
Headset Pro and the Goldline microphones but at the worst, you might have to
construct a simple one transistor pre-amplifier to use them with the K2.
I'm sure you will get responses from others who have use these microphones
with their K2's.

Have fun - it's quite the impressive rig!! 73 es gud dxing --don n4hh
K2/100/KAT100 #2028



-- 
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.298 / Virus Database: 265.6.7 - Release Date: 12/30/04