[Elecraft] Heil Proset question

[Jim Harris]

The stock HC4/5 elements (non Elecraft versions) in
their basic form produce a minus 65 db output.  This
is sufficient for use with some rigs other than an
Elecraft.  I use them straight with my IC-746Pro
without a preamp.  The Heil items sold by Elecraft for
the K2 has a built in preamp that boost their output
to a minus 40 db.  To power the preamp, +5vdc is
needed on the "AF" line between the K2 and the mic
element.  The K2 should have the higher level (-40db)
to attain full SSB modulation.  BTW, the numbers above
came directly from Bob Heil in an email exchange
between he and I.

When saying one gets good audio reports doesn't mean
that your K2 is fully modulated.  It just means there
is no noticable distortion to the listener.  The
actual received signal could be one to three "S" units
difference between the elements with and without the
preamp and without SSBA and SSBC adjustment in the K2.
 That is something similiar to adding a 200-500 watt
amplifier to your K2.  Yes, it is worth it to have the
correct level output from your microphone.

I use a preamp with my non K2 mics when using them
with the K2.  I got the preamp schematic from Don
Wilhelms website. (He offers tremendous
troubleshooting advice here on this forum.)  The site
URL is http://w3fpr.qrpradio.com/  I built a separate
+5vdc regulator supply for the preamp using +13.8vdc
from my Astron SS-30M power supply for my K2.

Hope that helps clear up some things for those who
have been wondering.  Have a great day.

Jim, AB0UK
K2/100 S/N 4787

I see that Elecraft offers a Heil Proset tailored to
the K2.  Ironically, I bought a Proset just a few
months ago with the HC4 element.

Can anyone tell me how superior the mic in the
Elecraft Proset is to the HC4 element in the set I
currently own?  (I'm really hoping someone will tell
me I can keep the set I have, but an objective opinion
would always be preferred!) 


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