On Fri, 23 Mar 2012 11:01:10 +0000, ND4jS wrote:
Hi all,
I am attempting to amplify a newly acquired multi elmac transmitter with
a henry 2kw. The power of the elmac is too high and i have tried
swamping it with a 50ohm dummy load in parallel with the amp. This
helped but the input is still a little too high. Any suggestions? Is
there a combination of resistors that can be used? Thanks. ND4jS. J
1: Google "Attenuator", or look in your ARRL Handbook. You don't want to
just put a resistor in series or in parallel -- you want an L pad or
(much better) a pi- or T-circuit attenuator. Note that you probably need
a Honkin' Big Resistor or three -- whatever power reduction you achieve
from the exciter to the amp has to get burnt up in the attenuator; it
needs to be able to handle and dissipate the resulting heat.
2: Have you tried just turning down the drive (if you're operating SSB)
or retuning for a lighter load (if you're operating CW)? Either one is
easy to do, and doesn't require any equipment beyond what you have
already.
--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?
Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com