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[TenTec] Scout frequency jumping, Enough!

To: <tentec@contesting.com>
Subject: [TenTec] Scout frequency jumping, Enough!
From: k5rov@earthlink.net (James Parsons)
Date: Mon, 01 Nov 1999 16:33:05 -0600
I agree with you, Tim. He was pretty extreme...

randas@mindspring.com wrote:
> 
> Gee Larry...95% operator failure...hummm... that seems a bit extreme to me.
> Should  a ham expect to have to put a "mobile rig" in an temperature
> controlled, stable environment with exact voltage to have good results..?? I
> agree that the scout is a fine rig...but its certainly not without problems.
> I think you took the discussion to the far left extreme. The true lies
> somewhere in the middle.
> 
> de Tim  K0FL
> 
> -----Original Message-----
> From: Larry Kayser <kayser@king.igs.net>
> To: tentec@contesting.com <tentec@contesting.com>
To: <tentec@contesting.com>
> Date: Monday, November 01, 1999 9:59 AM
> Subject: [TenTec] Scout frequency jumping, Enough!
> 
> >
> >Greetings All:
> >
> >This memo is to those who persist in trying to make a problem out of the
> >Scout's occasional propensity to change frequency under program control of
> >the internal microprocessor.  The microprocessor has the job of stabilising
> >the analogue VFO in this radio.
> >
> >In the last few weeks several amateurs have opinioned on this forum and
> >other forums that the Scout is getting a bad rap, the so called "frequency
> >jumping" is not a real problem.  My intention in this memo is to carry this
> >issue one step further, to categorise the blame for the problem into two
> >piles.  The first pile is the tiny minority of radios that actually have a
> >problem and need to be sent to the factory for service.  (see the PS below)
> >The second pile, and the vast majority of all the discussion here on this
> >forum and in other forms is the result of using the radio in a way that is
> >less than optimum and results in the radio responding by jumping around.
> >
> >I have a Scout.  I use it both mobile, fixed, and portable.  When someone
> >says it is jumping around I know immediately that I am doing something
> >wrong.  I know that I have RF feedback or I have a power supply with a
> >higher than acceptable internal resistance or I have a power cable that has
> >higher than acceptable internal resistance.  I can also tell that when I
> >operate the radio in a physically challenging condition, bouncing around on
> >the front seat, or in a temperature challenging environment, -25C in the
> >winter and the heater on full blast, that I am asking more of the radio
> that
> >I have a right to.   I also know that if the Radio is jumping around I have
> >done something wrong, I have a job to do to fix it, and when I have it
> fixed
> >I will not have a jumping around problem anymore.
> >
> >On this forum in the last three years I have found over a dozen different
> >references to frequency jumping that was resolved by fixing a problem
> >outside of the radio.
> >
> >If you have a frequency jumping problem remember that it is a 95% chance
> >that you are doing something wrong and further that you are broadcasting
> far
> >and wide that you do not know how to solve your problem!  The radio for 95%
> >of the time is telling you that there is a problem that needs fixing, only
> >approximately 5% of the time is the radio the problem maybe.
> >
> >Now lets talk about the one place were the radio has a design issue that
> can
> >not be overcome without some consideration by the operator.  If you are
> >operating CW at and over 30 WPM you must supply a .5 to 1 second time
> >interval from time to time for the microprocessor to get a reading of the
> >VFO frequency and apply the correction to the VFO.   The VFO is doing what
> >all analogue VFO's do, it is wandering along moving its frequency at some
> >rate per unit of time.  The microprocessor needs to measure the VFO
> >frequency, check what frequency the VFO was last moved to and then apply a
> >correction voltage to the VFO so that the frequency does not jump to the
> >next increment of change for the VFO.  What is the "time to time interval"?
> >I sense for a Scout operating in a non physically and non temperature
> >challenging environment it is every 20 to 30 seconds at a minimum.
> >
> >If you do not want to allow for the 1 second update interval buy a
> different
> >radio.  You will not get a radio with the low internal noise and the price
> >of the Scout that will meet such a requirement.  The lower price is the way
> >that Ten Tec found to not have to individually tune up the VFO's with
> >temperature compensating capacitors like they do for their other analogue
> >PTO's.
> >
> >Remember, when you complain about the Scout jumping around your really
> >displaying your inability to deal with your problem - you might not like
> the
> >message, but you now know plainly what your peers think when they see the
> >ongoing noise about this radio, 95% of the time.
> >
> >Larry
> >VA3LK
> >
> >PS  How does one know if a Scout VFO needs service?  This is an area that
> >the factory could have put more attention to in my opinion.  The
> information
> >you need is at what rate is the VFO drifting and how often is the
> >microprocessor having to apply a correction to the radio to keep it on the
> >frequency it is set to.  It would be ideal to have some indication from the
> >radio as to what the rate of change of the VFO and the corrections applied
> >by the mircroprocessor are.  This would help the user understand the
> >performance of the radio and become part of the solution rather than a lack
> >of information encouraging the user to become part of a perceived problem.
> >This is a design philosophy issue that Ten Tec should not be expected to
> >discuss in public.
> >
> >
> >--
> >FAQ on WWW:               http://www.contesting.com/tentecfaq.htm
> >Submissions:              tentec@contesting.com
> >Administrative requests:  tentec-REQUEST@contesting.com
> >Problems:                 owner-tentec@contesting.com
> >Search:                   http://www.contesting.com/km9p/search.htm
> >
> 
> --
> FAQ on WWW:               http://www.contesting.com/tentecfaq.htm
> Submissions:              tentec@contesting.com
> Administrative requests:  tentec-REQUEST@contesting.com
> Problems:                 owner-tentec@contesting.com
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-- 

James (Jim) Parsons, K5ROV   USAF, Ret. Ham for 58 yrs.
k5rov@earthlink.net     QCWA, NWQRP, Fists, ARRL
EX: W1RLA, K5FBB, K4FEO, SV0WN (CRETE), SV0WN (RHODES),
DL4NC, DL4JP, KA2FC (JAPAN), KA2JP (JAPAN).
JOHN 3:16

--
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Submissions:              tentec@contesting.com
Administrative requests:  tentec-REQUEST@contesting.com
Problems:                 owner-tentec@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


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