Ummm...
Looking at the QST review of the Orion at (ARRL members only):
http://www.arrl.org/members-only/prodrev/pdf/pr0401.pdf
you'll see the cw keying waveform for external keying, on a time base of 10
ms per division, at 60 wpm. The rise time on the 2nd dit looks like 2.5 to
3.0 ms or so. So if the default rise/fall time of 5 ms was selected (they
don't say, but a reasonable assumption?) then indeed the actual time is off
by roughly a factor of 2 like you say. This is interesting.
But in the same review they rave about the keying: "...the actual CW signal
is very clean. We got favorable reports on the air, with keying sidebands
falling away from the carrier frequency more rapidly than any other
tranceiver we've tested." This agrees with my own experience using external
keying... when monitoring on another rig, I've never detected any clicks now
matter what the rise/fall time setting or keying speed. Reports, usually
unsolicited, are always very positive (using default setting of 5 ms
(indicated), usually around 15 - 20 wpm). In fact, I've never seen or heard
a complaint anywhere about Orion key clicks, but maybe I'm out of touch.
I can't reconcile these observations with the assertion that a rise time of
3 ms will "guarantee bad clicks". Further, if you believe the Orion manual,
anyone using external keying is in a hopeless position. This is because the
range of allowable times for external keying is 3 to 5 ms, with the default
being 5 (2.5 ms actual if the indicated value is off by a factor of 2).
As an aside, what's funny is that if you adjust it higher than 5 in the CW
menu the message "Max 40 wpm external keying" is displayed, yet one can run
the value all the way up to 10 anyway. Is it limiting the value to 5 when
keying is external? If so why display the higher values as the knob is
turned? Or is the rise/fall time set as indicated, regardless of what the
manual says, with the warning message being only advisory? Without a
monitoring scope one can't really know what's going on.
Certainly, if this discrepancy between actual rise/fall time and the
rise/fall time indicated by the Orion user interface is real then I'm
surprised that it hasn't been corrected by now. But would Ten-Tec really be
shipping the product if the consequence was terrible key clicks at the
default setting?
Am I misunderstanding the QST review data? Is this really a problem?
Bob NW8L
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Bill Tippett
Sent: Tuesday, November 15, 2005 3:36 PM
To: tentec@contesting.com
Subject: [TenTec] cw settings
Hi Ken,
>I use rise at 3 and get excellent
reports. also have heard few TT's
with too soft a keying.
Ouch...those reports are certainly not from anyone close or else
you must have a very low ERP station. 3 ms would guarantee bad clicks. 6
ms is as low as I would ever go, even for QRQ CW. Menu settings are about
twice what the actual rise/fall time is. ARRL recommends about 4-5 ms which
would equate roughly to a setting of 8-10 in Orion's menu.
Glad you're in California! :-)
73, Bill W4ZV
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