The standard two tone test does certainly tell you correct amp behavior in
regard to linearity. And, that is important, but not the full story when it
comes to splatter and buckshot. It's when we either have bad non-linearity,
and/or add in overmodulation that we get into really nasty signals out
there.
As to your question to a pulsed two tone test: I honestly don't know.
Someone who is better equipped techically than I am will have to answer that
for us, Verner. Good question, though.
73 de Ron, K5BDJ
-----Original Message-----
From: oz5tg <oz5tg@post2.tele.dk>
To: amps@contesting.com <amps@contesting.com>
To: <amps@contesting.com>
Date: Monday, March 06, 2000 2:53 PM
Subject: Re: [AMPS] SSB interference
>
>Would a pulsed two-tone modulation reveal something ???
>
>OZ5TG, Verner
>
>----- Original Message -----
>From: rb <rbigg@pcola.gulf.net>
>To: <amps@contesting.com>
>Sent: 6. marts 2000 18:11
>Subject: [AMPS] SSB interference
>
>
>>
>> Peter (SM2CEW) and others have raised some interesting points about
>"dirty"
>> SSB signals heard during a contest this weekend. The topical points this
>> raises are interesting.
>>
>> I'm certainly personally an adovcate of having a good, clean signal. The
>> problem is, I don't know how to do that without resorting to asking for
>> on-the-air signal reports, which, fortunately, I get every day I'm on the
>> air through guys on the net I check in with. Let me explain why I
>otherwise
>> don't fully know what kind of signal I'm putting out.
>>
>> I'm sitting here with a nice matched exciter, final, and monitor scope.
>> WOW! What more could a guy want, you say??? Well, believe it or not, I
>> still don't know of a way to tell the composite quality of my transmitted
>> signal.
>>
>> Yes, the exciter and final are hooked through the monitor scope. So what
>> does this do for me? Well, in one switch position, I can look at Sine
>Waves
>> dancing around over the screen of the scope. These fluctuate in width
and
>> amplitude with speech, and vary so fast that I really can't tell if I'm
>flat
>> topping or not. The other test I can run is to use the oscillator in the
>> scope to inject a two tone audio signal into my rig and then look at a
>> trapezoid screen pattern. This test does indeed tell me if/when my final
>> isn't behaving in a linear manner. But, it is only useful with the tone
>> injection, and doesn't tell me anything about transmitted signal width
>> and/or buckshot/splatter when speech is present. It tells me what the
>final
>> is doing in a steady state condition.
>>
>> So, given the above, is there any simple, practical way of getting a good
>> idea of what kind of signal my rig is putting out? I have a feeling
there
>> may be a fair number of hams out there who would like to know the answer
>to
>> this question. Please keep any answers as non-tech as possible. I'm
sure
>> that by now the 8,000,000 or so hams reading the mail on this reflector
>have
>> figured out that I'm not a rocket scientist or brain surgeon by
profession
>> or training.
>>
>> I don't want to ever put out a bad signal. I'm thankful that I have a
>> means, through other hams on the net I check into, to give me a reading
of
>> relative signal quality. Is there a better way?
>>
>> 73 de Ron, K5BDJ
>>
>>
>>
>>
>>
>>
>>
>>
>> --
>> FAQ on WWW: http://www.contesting.com/ampsfaq.html
>> Submissions: amps@contesting.com
>> Administrative requests: amps-REQUEST@contesting.com
>> Problems: owner-amps@contesting.com
>> Search: http://www.contesting.com/km9p/search.htm
>>
>>
>
>
>--
>FAQ on WWW: http://www.contesting.com/ampsfaq.html
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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