On Mon, 2 Dec 2002 16:15:33 -0600
"Chuck Lewis" <clewis@knology.net> wrote:
My experience.
This day I set the controlebox in the window here in the shack, so that I could
touch it from outside, and still have a look at the beam.
The beam is standing in its position, but the needle is flucturing wildly.
> Erik,
>
> These rotors use DC to actuate the drive motor. The drive voltage and
> position indication signal (also DC) both pass through the rotor cable and
> all its connectors. Any leakage current from the drive voltage appearing on
> the signal line can cause an erroneous position signal to be sent to the
> control box whenever the drive is commanded. The needle will swing
> erroneously until the drive voltage is removed, then settle back to indicate
> the correct position. It will swing in either direction, depending on
> whether the rotor is commanded clockwise or counterclockwise (drive polarity
> is reversed).
>
> When this happened to my 800SDX, I measured resistance at the lower end of
> the rotor cable and found erratic and intermittent leakage between the drive
> pins and the indicator pins and ground. As I recall the schematic, there
> should be no continuity between the drive lines and ground. I then checked
> the connector at the rotor. There was a lot of insect debris moistened by
> rain, condensation or whatever inside the cable connector. Evidently (and
> not surprisingly), the flexible connector boot does a poor job of
> weatherproofing. Anyway, when I cleaned the mess out of the connector (both
> front end and backshell), the resistance readings returned to normal, and
> the system behaved correctly when reconnected to the control box. This is
> consistent with the fact that the erratic behavior always followed a
> rainstorm and recovered after a few warm, sunny days! I filled the front end
> and backshell with non-conductive grease and taped the connection with
> Scotch 88. That was two years ago...it took a couple of trips up to the
> rotor, but the problem has not returned. I was very happy to avoid removing
> the rotor for servicing.
>
> I can also believe that a lightning pulse could clear the short too, for a
> while, until something tries to again use the connector as a home.
>
> Try this before you undertake a rotor removal!
>
> Good Luck!
> Chuck, N4NM
>
>
> ----- Original Message -----
> From: "Erik Jakobsen" <erik@urbakken.dk>
> To: <towertalk@contesting.com>
> Sent: Monday, December 02, 2002 2:54 PM
> Subject: Re: [Towertalk] RE: Yaesu G1000SDX
>
>
> > On Mon, 2 Dec 2002 15:36:29 -0500
> > "Rudy Marcelletti, K8SWD" <rudym@net-link.net> wrote:
> >
> > > Erik: You take a lightning hit? I don't computer control my G1000SDX,
> but you describe what mine did for a while after a close strike, or direct
> hit--I don't know which. The needle would spin around uncontrollably and
> sometimes point in the right direction, sometimes not. When I would look
> outside, the antenna was aiming correctly where I had the preset pointing,
> but the needle would spin wildly, but would eventually stop in the vacinity
> where I was pointed. Well, this summer I took another hit--direct I think.
> It wiped out about $3,500.00 of on non-ham stuff in the house, but only 2
> ham power supplies. My rotor is now FIXED! No explanation for it other
> than something up top was loose as my controller was disconnected at the
> time of the storm, and lightning fixed it!
> >
> > Hi Rudy.
> >
> > So far I do not know about a lightning attack here :-).
> >
> > I'm not quite sure if the antenna is being rotated with the same speed as
> the needle does. But of course I'll have a look at it.
> > Will give it a try with the presets. Once I was out it seemed that the
> antenna did rotate according to the needle, but I'm not sure.
> >
> > Well I'll be back when I have done the test.
> >
> > Tnx for your kind replying.
> >
> > > Rudy Marcelletti, K8SWD
> > >
> > >
> > > --- StripMime Report -- processed MIME parts ---
> > > multipart/alternative
> > > text/plain (text body -- kept)
> > > text/html
> > > ---
> > > _______________________________________________
> > > AN Wireless Self Supporting Towers at discounted prices,
> > > See http://www.mscomputer.com
> > >
> > > Wireless Weather Stations now $349.95. Call Toll Free,
> > > 888-333-9041 for additional information.
> > > _______________________________________________
> > > Towertalk mailing list
> > > Towertalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> > >
> >
> >
> > --
> > Med venlig hilsen - Best regards.
> > Erik Jakobsen - erik@urbakken.dk
> > Registered Linux user #114875 - http://counter.li.org
> >
> > _______________________________________________
> > AN Wireless Self Supporting Towers at discounted prices,
> > See http://www.mscomputer.com
> >
> > Wireless Weather Stations now $349.95. Call Toll Free,
> > 888-333-9041 for additional information.
> > _______________________________________________
> > Towertalk mailing list
> > Towertalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
>
>
>
> _______________________________________________
> AN Wireless Self Supporting Towers at discounted prices,
> See http://www.mscomputer.com
>
> Wireless Weather Stations now $349.95. Call Toll Free,
> 888-333-9041 for additional information.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
--
Med venlig hilsen - Best regards - vy73 de OZ4KK.
Erik Jakobsen - erik@urbakken.dk
Registered Linux user #114875 - http://counter.li.org
|