http://www.users.on.net/~jscones/GWX/download.html

Please look under optional mods.

Ok, this may be off topic, but since we are on the topic of newbie questions, I have one I haven't figured out/can't remember.

If playing GWX, with Map Contacts off - will you ever get a RDF hit that shows you where a boat is nearby?

I play in very low time - and haven't ever seen it happen. The most I have gotten is radio reports from Bdu, but I can't ever remember having a contact show up in my vicinity - should I enable Map Contacts for that?

Thanks for any responses to the newb question.

Tchuss,
Notewire

Sorry to bump this old thread, but does someone have a mirror for this site?

http://www.users.on.net/~jscones/GWX/download.html


I'm constantly getting 404'D

Look Here - http://www.subsim.com/radioroom/showthread.php?t=102096

:up:

what controls the raising/lowering of the DF antenna? How is that coded? :hmm:

I know this is going to be a little pedantic, but it isn't a dipole, it's a loop.

The RDF loop on u-boats (and just about all other craft at that time) was for low frequency use, near 500 KHz. A characteristic of small shielded loops is that they have two very sharp nulls which are useful for finding the direction to a station. The only problem is that you will only get a line of bearing, ie., the target could be at 270 degrees or 90 degrees, because without a sense antenna to resolve the ambiguity, there is no way to tell which direction the signal is coming from.

The intended use of these antennas was to get bearings on known beacons in fixed locations. In that case, the ambiguity is resolved: If you are in the North Sea and you get a line of bearing like 135/315 degrees true for a station in Germany, then you know it has to be 135 degrees. The idea was that you could take bearings on two or more stations, and where the lines overlap on the map is your location.

They were also used by boats in wolfpacks to home in on a beaconing boat that was shadowing a convoy. Beaconing was used because various navigational errors by both boats could place the intercepting boat miles away, whereas with a beacon signal and an idea of the general direction to head, you can intercept easier. You can also take a bearing, run in a straight line at high speed for an hour or so, take another bearing, then you have two bearings, and a general idea of the location of the beaconing boat.

It is possible to make a dipole to receive these beacons, but a full sized dipole for 500 KHz would be just under 900 feet long, not very feasible, and in any case the null off of the ends of even the best dipole is nowhere near as sharp as the nulls on a shielded loop.

nice write up!