| From what I have heard, the RayJeff is a good line. The best buy
from a functional as well as reliability standpoint is reputed to
be the Ratheon RAYNAV 570.
I got one as a present as well. It was purchased from NEPTUNE Trading
Corp. in Harrison,NY (800-637-0660). Cost was $599.00.
Carl
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| I have a RayJefferson 990 Loran that is driving me nuts and I need some
help figuring out what is causing my problem....
I can turn on my Loran, in my slip, let it lock into the SE quadrant
signals, check out the SNR and signal strength (which are all great),
put it on the display to show either TD or Lat/lon with bearing and
speed and watch the fun begin.
While I am in my slip, my loran varies in its bearing reading 120
degrees and tells me I'm doing anywhere from 1.2 to 35 knts! I've got
it set to give me an average every 3 minutes, but the scale is updating
far faster than that. I'm also showing to be in a location about
2degrees away from where I really am, but I figure some offsets can be
put in to fix this problem.
Needless to say, I have ZERO faith in this equipment until I can get it
settled down and at least consistent. Any ideas anyone?
The Antenna is approx a 6ft whip mounted on the aft of the boat, base
at the top of the cockpit (if this helps any). When underway out of the
marina I have the same problem, so I don't believe its a reflection
problem. It occurs consistently whether it's day or night.
Help!
Robert
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| > While I am in my slip, my loran varies in its bearing reading 120
> degrees and tells me I'm doing anywhere from 1.2 to 35 knts! I've got
> it set to give me an average every 3 minutes, but the scale is updating
> far faster than that. I'm also showing to be in a location about
> 2degrees away from where I really am, but I figure some offsets can be
> put in to fix this problem.
I'm going to assume that the loran is not broken. First, any bearing
readings while you are not moving are quite likely to rangy widely. The loran
is trying to figure out what direction you are moving by monitoring the slight
differences in the propagation calculations inherent in this type of device.
The bearing will therefore range widely. I'd expect a little speed but not
what you are seeing. For the loran to come to these conclusions, it would
have to see that kind of descrepency in the TD's. Also, if the loran is
really reading 2 degrees away, it isn't just because you haven't turn on the
automatic Additional Secondary Factors (ASF). The loran has auto ASF doesn't
it?
I would get the owners manual and turn to the section on initialization.
It looks like the loran is assuming the wrong location for the TD pair. Each
TD can occur on 2 location on the earth. You have to tell the loran which one
to start with. It then can keep track as you manuveur around. If the loran
was initalized far away, and you bought it out of state, installed it and fired
it up, it'd be confused.
The wide speed ranging may be due to not having a daynaplate which
bolts onto the bottom of the boat so the loran can use the conductive ocean
as a ground plane for the antenna. The loran frequency is VERY low (100 khz),
and the ground plane is required. The dynaplate may help when the weather
gets sour also.
Check all antenna coaxial connections for corrosion also.
Good Luck
Dave
p.s. I agree, I'd not trust it until the speed and location problems are fixed.
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