Jerry:
Thanks for the comments.
From: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
Precedence: list
Subject: Re: [TenTec] Orion II key click report
Date: Mon, 29 Jan 2007 12:26:10 -0600
On Sun, 2007-01-28 at 13:15 -0600, William Q Meeker wrote:
How much drive power does the PA take?
I get near legal limit with 50 watts output, so never run more that
when the A99 is on. I usually have it somewhat lower, however, not
feeling the need to push the limit, even when barefoot.
The Orion is a bit notorious for
setting power only with the ALC while keeping drive up (no adjustment
for drive in CW mode) which tends to make a sharp corner when the rising
power gets to the power setting, instead of the desired rounded corner.
I followed the related discussion a couple of weeks ago about the
relationship between the power setting and ALC operation on SSB and
have been usefully applying what I learned in that discussion to my
AFSK operations.
I do not know the inner working of the Orion II, but things seem
different on CW. The ALC light always comes on strong when keying,
regardless of the setting of the power control (unlike SSB
operation). Tonight I looked at the keying wave form with the power
setting varying over the entire range from 1 watt to 100 watts. To my
eyes, as the power setting changed, I could see no difference in the
in the ALC light or, after amplitude adjustment, the shape of the
keying wave form .
Perhaps someone else with better eyes or measuring equipment has
looked at this carefully for the Orion II?
Slower rise time doesn't force that top corner rounding. You might try
inserting attenuation between the Orion and the PA to allow the Orion to
run full tilt so the top corners on the envelope are rounded.
I like the idea that my exciter is operating at a comfortably low
level. I would think that this would have the effect of extending its
life (in any data that I have ever seen, higher stress leads to
shorter life---and my wife keep reminding me about this!).
Scopes are notoriously poor about triggering on modulation envelopes,
they'd rather trigger on the individual sinewaves of the carrier.
Triggering on the audio or the key closures is more reliable.
I will have to rig something up to do this, when I get some free time.
73,
Bill
K0KT
73, Jerry, K0CQ
William Q. Meeker
Department of Statistics
304C Snedecor Hall
Iowa State University
Ames, Iowa 50011
Phone: 515-294-5336
Fax: 515-294-4040
Home Fax: 515-232-1323
www.public.iastate.edu/~wqmeeker
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