Jack: The Power control on the Orion is actually an ALC threshold control,
so as you drop the ALC threshold to hold the power to a lower level, you
should also drop the audio drive level. 5 Watts is 13 dB below 100, so I
would drop the audio down by that amount. An easier way is to decrease the
level as far as you can while still having the ALC light flash.
That may not be the ultimate reason you got a report of splatter. Solid
state RF amplifiers are designed to have best efficiency and lowest IMD at
their design power level. Deviating significantly from that power level can
increase IMD. The best test is to look at the signal on a spectrum analyzer
using a two-tone test. I have done this on the Orion II in the 40-100 Watt
range (looks very clean), but never at QRP. Next time I get a chance, I'll
try that and see what it looks like.
Ron N6IE
www.N6IE.com
----- Original Message -----
From: "jack" <jfriend31@comcast.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Tuesday, February 03, 2009 7:24 PM
Subject: Re: [TenTec] Orion at QRP levels
>i have had good reports on CW using the Orion turned down to 5 watts or
> less. no indication of any negative sort in that mode.
> jack ak7o
>
> ----- Original Message -----
> From: "Ralph Matheny" <mathenyr@marietta.edu>
> To: <tentec@contesting.com>
> Sent: Tuesday, February 03, 2009 7:06 PM
> Subject: [TenTec] Orion at QRP levels
>
>
>> This past weekend I wanted to make a few Q's in the QRP SSB contest, so
>> I cranked down the Orion to 5 Watts and called away. In a few minutes,
>> I received what I believe was an accurate report that the signal was
>> broad and producing "splatter". After giving some thought, it seems
>> obvious that resetting the mike gain, speech proc, etc. are probably
>> needed in order to use the Orion at low power levels. I also suspect that
>> the 100-watt amp could be both a good 100-watter and a 5-watter without
>> bias adjustment, at least for SSB.
>>
>> Does anybody else use the Orion at QRP?? Problems or results?
>>
>> Ralph Matheny
>> K8RYU
>> 207 Gibbons Place
>> Marietta Ohio 45750
>> mathenyr@marietta.edu
>>
>>
>>
>>
>>
>>
>>
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