| Title: | SAILING |
| Notice: | Please read Note 2.* before participating in this conference |
| Moderator: | UNIFIX::BERENS |
| Created: | Wed Jul 01 1992 |
| Last Modified: | Mon Jun 02 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2299 |
| Total number of notes: | 20724 |
Hi,
I'm looking for a little advice or guidance from any Radar experrts
out there (or anyone who has seen a similar problem)
I have a Raytheon R20 in it's third season that has performed
better than I even expected; but, on a recent vacation it started
doing a strange thing (hard to describe; but, here it goes):
It powers up and runs just fine for about 45min or so then it seems
to draw a pie shaped set of lines from the center of the screen
right out to the edges covering about 10 to 20 degrees of the screen.
This 'stuff' comes & goes - at varying bearings around the screen
- every now & then covering up to about 1/2 the display.
While this occurs the 'normal' echo's seem to display correctly;
but, do get painted over by the pie shaped garbage.
The lines seem to be straight and are not quite solid - a bit dashed.
Now at first I thought it might be noise from other radars; but,
I had the Interferrence rejection turned on.
I also thought it might be some Racon beacon running amuck; but,
it happened again about 50 miles later & in neither case could I
locate a near by Racon.
I don't feel like pulling the whole unit to bring it to a shop so
I tried a few phone calls to get some advice -- (read add confusion)
I haven't had a chance to look at these possibilities yet:
Raytheon Product Support on the west coast says "Re-adjust your
tuning" - Doesn't seem to make sense to me.
Raytheon Product Development in Hudson N.H. says "Loose connection
or the reed sensor that counts the revolution is loose & it's
displaying your ship heading marker at varying spots" - Doesn't
make sense as it seems to accur only after running awhile?
Joe Random Repair shop says "It was either a Racon running amuck
or you Magnetron is aging & you'll need a new one ($200+) - I guess
it could be the Magnetron (believe it or not they are only guaranteed
90 days) but in 2+ Seasons that seems scary - even if I had it on
all the time that would be <300 hours.
So - If anyone has any thoughts I'd appreciate hearing them.
I'll document the final resolution here whenever I find it.
In the meantime - have a Good Season All,
Lou
p.s. At least it worked just fine when I arrived at Cuttyhunk in
<100' visability and found out I missed reading the Local Notice to
Mariners that informed me (or should have) that they changed all
the bouyage there this past April -- Lord was that Fun :>)
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1565.1 | loose wires? | LANDO::SCHUMANN | Thu Jul 26 1990 10:34 | 27 | |
> It powers up and runs just fine for about 45min or so then it seems
> to draw a pie shaped set of lines from the center of the screen
> right out to the edges covering about 10 to 20 degrees of the screen.
> This 'stuff' comes & goes - at varying bearings around the screen
> - every now & then covering up to about 1/2 the display.
> While this occurs the 'normal' echo's seem to display correctly;
> but, do get painted over by the pie shaped garbage.
> The lines seem to be straight and are not quite solid - a bit dashed.
Because this happens in a particular subsection of the screen, I suspect it
is related to the rotation of the antenna. I don't know anything about radars,
let alone this specific radar, but I'd take a look at the integrity of the
connections (sliders?) to the rotating antenna. Also look for the possibility
that the antenna unit has been whacked, and the rotating part is out of balance.
The above assumes that the bearings of the noise are in a constant region of
the screen, i.e. a constant range of antenna positions relative to the mount.
If the noise appears at truly random bearings, the problem may be as simple
as an intermittent antenna wire connection. To test for this, have someone
jiggle the antenna wires near connectors and see if the problem can be induced
or cured by fiddling with the wire.
--RS
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| 1565.2 | Loose wire... | ALLVAX::DENNERLEIN | Friends don't let friends drive Chevys | Thu Jul 26 1990 13:44 | 26 |
Don't underestimate the inteligence of a loose wire. Loose wires are
trained in forcing owners to loose lots money on expensive repair bills.
They are given college degrees in how to fool owners and mechanics with
minors in making you look like an idiot. Believe me, I'm speaking from
experience, they can make you feel very foolish and very poor. I
haven't had the problem on any boats yet, but I've had it on Cars.
My Car forced me to take it to a mechanic a couple of times, not drive
at night for several months, and finally it forced me to by another
car. Then for 9 months, I went out to the old car and checked it over
looking for the problem, cause I couldn't sell it with the problem it
had. final after 9 months and plenty of research in notes files,
manuals and charts, I went out to clean up some of the motor and found
one of the main wires was almost completely off the motor. I got a
wrench tighten the bolt that holds it on the motor and lived happily
ever after. I still drive the old car, since sold the other car
I know we are talking about a cars here when we should be talking about
boats and radar, but it's the same thing. The problem you are
discribed sounds like the same type of thing. A loose wire. Loose
wire hunting is not a fun sport, it takes time and patience. Keep
track of when you notice it happening, what the boat is doing, the
weather conditions, anything that might give you a clue where the
connection is. Then go and check EVERY connection. As with all things
electrical, if your going to have problems, it's probably going to be
with the cables.
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| 1565.3 | Same problem? | WEDOIT::JOYCE | Mon Jul 30 1990 08:32 | 8 | |
I have the same radar, which has been getting a lot of use lately,
it's having the same problem as re: .0 . I've checked all the
connections, in fact, I cut off and soldered all the crimped wire
ends in the antenna. Its only a problem on the higher ranges >8
miles. Playing with the tuning will almost get rid of all the
noise spikes.
Steve
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