loran questions
"RB" wrote in
:
Got a question on LORAN sets. I don't want to get into the
desireability of GPS as the nav mode of choice today. I'm fiddling
around with LORAN and trying to get going with it.
1. What is/are LORAN operating frequencies?
100 Khz, all stations are on the same frequency, exactly. They use a
cesium beam frequency standard to make sure it's perfect.
2. Marine LORANS are found with external couplers (pre-amps) which go
at the base of the fiberglass/whip antenna. Can marine LORANs which
are made for use with external couplers give reasonably good
performance without the coupler? Or, is lack of the coupler a
"killer"?
Killer. The very-low frequency LORAN antenna is electrically 2340' long
(1/4 wavelength on 100 Khz). To achieve this in an 8' long whip it is
VERY heavily loaded with a large inductance and that coupler. No, you
can only get it working with the cou0ler or a 2,340' long whip, your
choice.
2. Are there marine LORAN receivers which don't require external
couplers (i.e., that hook direct to the antenna)?
The couplers on the marine antennas are built into the whip. They're
still there.
3. If you have a marine LORAN which does in fact need an external
coupler to get enough signal through and you don't have the companion
coupler unit, are any commonly available pre-amp boards for the LORAN
frequencies available? If so, where find?
It's not a preamp problem. There's tons of signal from teh MEGAWATT
LORAN-C pulse transmitters and their massive capacitor hat loaded 850'
tall antenna towers. The problem is that 2340' 1/4 wave whip it takes to
hook 'em up.
You need the antenna system it came with.....
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