Radio Directional Finder

[gts1544]

cal40john, I can't speak to the nautical technicalities, but on aircraft ADF systems (automatic direction finding), we had both the rotating (mechanical or electrical) directional antenna, which could resolve the direction of the transmitting antenna to within 180 degrees, but you couldn't tell which direction without the sense antenna, which was a simple single wire from cabin top to tail. This sense antenna, through the circuitry, resolved the ambiguity. Make sense, no pun intended? gts1544

[spearfish]

It was the heady days of the early 80s, when only mil had gps towards late 80s use to be called p code, as it was v accurate then the civil models were made a fraction less accurate, but DF was the old Decca and loran systems oh how bad these things were, u they had to apply deveation and variation errors, big pool of errors, god i hated it every hour pool of errors or every watch, still have the notes somewhere, i would be surprised if most stations hadnt shut down due to Satnav,

[roverhi]

The last US Loran station shut down several years ago. AFAIK Loran receivers are totally useless now. Occasionally someone tries to sell one on Ebay or Craig's List. Don't know whether they are clueless or scammer trying to nick the unwary. Knowing Craig's List, it's probably the latter

[Hudson Force]

I used an RDF from the 70's into the early 90's. I skipped LORAN and I remember the first GPS units were at around 4 or 5K. With the obvious knowledge of the sun rising in the east and setting in the west, I never needed to distinguish between the two nulls. If a weak station was lost to my hearing at 95 degrees and on the sweep I could hear it again at 119 degrees then the bearing was 107 degrees,- worked well. I could still use airports and radio stations until the GPS costs came down to about $200. From south Florida to the Bahamas I could always pick up West Palm Beach, Jupiter Inlet, West End and Eggmont Key.

[Richard5]

RDF and ADF receivers are good for detecting lightning discharges. Intensity of the discharge and relative bearing could be gotten. In 2007-2008 the radio in my truck would receive the beacon located on Adak Is. in the Aleutians. I was in central California.