There was fix for mechanical stability posted a while back. The fix is
to shorten the leads from the PTO coil to the circuit board so that they
are short and stiff. Also treat the wire spring that rides along the
brass shaft on the outside of the PTO with a conductive grease. This
wiper spring is a ground connection and any resistance here causes
frequency jumping when the PTO is tuned. I used De-Oxit on mine. Tack
bonding components with epoxy will also help.
I plan to shorten the coil leads on mine this weekend.
Also, it wouldn't hurt to treat the contacts on the band modules with
De-Oxit.
73,
Bob WB2VUF
robert k stephens wrote:
>
> Well this is getting interesting
>
> I'm beginning to think that some Scouts do indeed have a real frequency
> instability problem but I think it may might have more to do with
> *mechanical stability that with the basic electronic design.
>
> First a quick review
>
> Stuart likes his Scout and does not experience drift problems or frequency
> jumping
>
> Perry has used a Scout 7 years cm/mobile with internal keyer 30 to 40 wpm
> and does not experience drift or frequency jumping problems.
>
> Ron likes his Scout but does notice a small problem with mechanical
> stability on rough roads
>
> Steve has had the experience of hearing many jumpy Scouts on the air.
>
> Larry says W4SON's Scout did not jump
>
> Steve says W4SON's Scout did jump
>
> I think that Jerry is on to something when he comments that mobile rigs get
> more shock and vibration and therefore need to be solidly soldered and be
> put in a stiff case. He also mentions cleaning:
>
> My experience:
>
> When I first got my Scout I had no problems with drift (I had some RF
> problems apparently due to installation). As I remember it I had no
> problems with drift. I don't think the microprocessor corrected for drift
> more than once or twice per hour when I operated the Scout indoors. I
> checked in to local cw and ssb nets as well as other types of operating.
> One of the local guys hates Ten Tec and would have given me a bad report
> if he could have, but everyone said the rig sounded grest and plently
> stable. I repeat -"no reports of frequency jumping"
>
> However, after a while I started having intermittent problems. Now and then
> I could watch my frequency fluctuate and then go back to being stable. I
> began getting occaisional reports of intermittent fm-ing.This became worse
> over time and the rig is now at the factory.
>
> My experience is that a properly working Scout does not have frquency
> stability problems. I assumed that the problems that later developed in
> mine were unique but I'm begining to suspect they are fairly common and
> possibly releated to construction rather than design.
>
> My Scout often rode on the floor of my sub compact car while driving over
> roads consisting mostly of pot holes. I suspect that I am having problems
> because my Scout connections have been shaken loose. I've talkd with
> several Scout owners who experienced problems with the modules becomeing
> loose and connections becoming poor. I also suspect that many Scouts are
> operated in dirty conditions and the connections need to be clean often.
>
> I'm just wondering how many of the jumpy Scouts that Steve hears need to be
> cleaned, or resoldered.
>
> I'm guessing that W4SON's rig may have worked fine when new but developed
> problems as it aged ?
>
> I realize I'm doing too much speculating. When I get my rig back from the
> factory I'll test it out and post the results until then I'll try to stop
> speculating and wait patiently ;-)
> 73
> Bob KB1CIW
>
> At 10:08 PM 3/2/02 -0500, Steve Ellington wrote:
> >Larry. Are you saying that Jack W4SON's Scout didn't jump or he at one time
> >had a prototype that didn't jump? I remember his Scout as a real jumper. It
> >finally went up in flames along with his amplifier and screwdriver antenna
> >when his catalytic converter burnt his VW Jetta to a crisp. He now runs an
> >IC-706. I think most die hard cw Scout users have since switched to other
> >rigs out of despiratation.
> >
> >Steve Ellington
> >N4LQ
> >----- Original Message -----
> >From: "Larry Kayser" <kayser@sympatico.ca>
> >To: <tentec@contesting.com>
> >Sent: Saturday, March 02, 2002 9:04 PM
> >Subject: [TenTec] Re: Scout instability, revisionism, please stop
> >
> >
> >> Gentlemen:
> >>
> >> Let us please remember that the Scout that Jack, W4SON/2/M was using in
> >the
> >> Scout prototype days (and the one that Jack Burchill was using mobile at
> >> the same time) for the Scout had NO frequency jumping problems and the
> >> manual of the early Scouts said nothing about frequency jumping at all.
> >>
> >> This revisionism has to stop, the simple fact is that in hind sight a
> >lousy
> >> design decision was taken. The explanations later have nothing to do with
> >> the decision process in Ten Tec that made the Scout the way it is.
> >>
> >> Larry
> >> VA3LK
> >>
> >> _______________________________________________
> >> TenTec mailing list
> >> TenTec@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/tentec
> >>
> >
> >_______________________________________________
> >TenTec mailing list
> >TenTec@contesting.com
> >http://lists.contesting.com/mailman/listinfo/tentec
> >
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