I put down as many as I remembered that were less than 30 years old.
Point is well made that this list is for discussion of all Tentecs,
their care, and use and so that makes test equipment and antennas also
fair game. I'm question driven, so I probably won't start discussions.
On 7/14/2010 6:16 AM, Paul Gates wrote:
>
> Jerry, K0CQ did not go far enough! I want see some discussion on Triton IV,
> Delta, etc... Just kidding of course. Don't laugh b ut my primary rig is a
> Delta 580 that is.
>
> KD3JF
>
> Paul Gates
>
>
>
>> From: janed@burgoyne.com
>> To: geraldj@weather.net; tentec@contesting.com
>> Date: Tue, 13 Jul 2010 09:37:44 -0600
>> Subject: Re: [TenTec] more oscilloscope questions
>>
>> Maybe Paul could start a thread for the solution for checking all those
>> things such as splatter, clean signal such as people that are blind. go for
The scope is the handiest tool for detecting splatter other than a
spectrum analyzer which really only works well with 2 tone test signals
for measuring because with two tones the frequencies of the intermod
products are predictable while with voice they are more continuous
across the band.
The first check with a scope is to drive the rig key down in CW to see
the peak power as controlled by ALC. Make note of that, by setting the
scope gain to fill between the first graticule line down from the top
and the first garticule line up from the bottom of the display. Then go
to voice and notice that going more than a few percent above that the
rising spikes get cut off. That's what makes splatter, the envelope
clipping from where the collector (or plate) voltage can't swing any
more without going negative on the low side of the swing (or below the
screen voltage on a tube where suddenly the plate current goes to zero
and the screen current rises to replace the plate current to the
detriment of the screen). The clipping point on SSB may be a little
above the maximum CW carrier due to power supply dynamic regulation and
some time delay in the ALC circuit. For those unable to see the
oscilloscope, its not so much help, but listening with a well shielded
second receiver tuned a few KHz off the transmitted signal (shielding
needed to keep from overloading that receiver) will show up splatter or
intermod products. Or sometimes listening to the transmitted signal the
distortion of the PA clipping is detectable to the astute ear.
>> it. 73
>> Ed K7UC
73, Jerry, K0CQ
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