Key Clicks? Huh?
----- Original Message -----
From: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, January 29, 2007 1:26 PM
Subject: Re: [TenTec] Orion II key click report
> On Sun, 2007-01-28 at 13:15 -0600, William Q Meeker wrote:
>>
>> I have been playing in the CQ WW 160 meter contest over the weekend.
>> Last night another ham, about 20 miles away spotted me on the cluster
>> with the comment "with clicks." I am using my Orion II (version
>> 2.037j) and was running close to the legal power limit (Alpha 99)
>> with a separate receiving antenna so that I do not have to exercise
>> the A99's relays.
>>
>> After that report came through I immediately checked the setting in
>> the Orion II and it was at the recommended default of 5 ms, and
>> because I have never had any other reports like this in the 5 months
>> that I have had the Orion II, and I know that strong stations can
>> overload a receiver to cause clicks, I just continued on.
>>
>> This morning, after the band closed, I hooked up my monitor scope to
>> have a look. The wave form looks good, but I have not figured out
>> some kind of standard so that I can measure the exact rise/fall time.
>> In looking at the archives of this list I saw an old posting that had
>> measured the actual rise/fall times against the settings and found
>> that the actual times were less. To be safe, for now I changed the
>> Orion II to 7 ms.
>>
>> A few questions:
>>
>> 1. Has anyone measured the rise/fall times in this version of the
>> Orion 2? How accurate is the rise/fall time setting of the Orion II?
>> And of course, as a statistician, I wonder if this is consistent over
>> different units. If several people have done the measurements, we
>> could sort this out.
>>
>> 2. If my rise/fall times are set a 5 ms, and the wave form shape has
>> the right shape on my scope, could I still be creating objectionable
>> clicks?
>>
>> 3. What other things should I do to check for the clicks?
>>
>> 4. In the Orion II manual (October 2006 version) on page 31 is says
>> that "For external keying the rise fall times available are 3ms to
>> 5ms regardless of the keyer speed." I can adjust between 3 and 10, so
>> I suppose that this is a typo?
>>
>> Bill
>> K0KT
>>
>>
>>
>>
> How much drive power does the PA take? 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.
> 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.
>
> 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.
>
> 73, Jerry, K0CQ
>
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