[Elecraft] unequal tone power output in FSK

[Dave Hachadorian]

Are you sure you are seeing unequal steady-state power on mark 
and space?

What I see on both of my K3's are significant (+/- 7%) power 
transients at the transition between mark and space.  These 
transients show up vividly on an LED wattmeter, and I see the 
screen current on a high-gain tetrode amp jumping like crazy. 
I've complained about it on the reflector a couple of times, but 
so far there has been no improvement.

The transients can be easily seen by hooking up a hand-key to the 
FSK keying line and alternating between key-closed and key-open. 
When the key closes, power momentarily spike upward.  When the 
key opens, power momentarily spikes downward.  Steady-state power 
is equal, key up and key down.

So far, nobody has complained about my signal, but amplitude 
modulation can't be a good thing on FSK.


Dave Hachadorian, K6LL
Big Bear Lake, CA




-----Original Message----- 
From: Mark n2qt
Sent: Thursday, August 25, 2011 2:41 PM
To: Elecraft at mailman.qth.net
Subject: [Elecraft] unequal tone power output in FSK

This was a thread a while back, (the twist in the tones is 
induced by
passband ripple in the filters, worse with 5 poles) and there was 
a
possibility of a software update to flatten the tones.  I know it 
doesn't
really affect anything, but watching the LEDs on the W2 flutter 
just
doesn't seem right.

Mark n2qt

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