Are radio direction finders completely obsolete?

[rslifkin]

Originally Posted by thomm225

More on current uses of Radio Direction Finders. (besides their use/requirement in the 2022 Golden Globe Race)

Radio Direction Finding: An Essential Tool for Search and Rescue

https://rhothetaint.com/radio-direct...ch-and-rescue/

Thinking about it, this thread hasn't been specific enough. I'd say they're obsolete for boat navigation, but they do still have other uses (in aircraft and for SAR or law enforcement to locate the source of a radio signal).

[El Pinguino]

Point of order - the Med - no matter what the Romans thought or some still think today - is not the centre of the universe.

People should read the OP again - no mention of small boats -

'Have radio direction finders become completely obsolete? Are any aircraft or vessels still using them? Are there still stations transmitting signals?'

My first boat came with a Newmar -101 which I wish I still had just for the radio.
My second boat came with something like a Homer but black? Maybe an Autohelm?

Replaced it with a DGPS.

Saw the effectiveness of RDF once in a typhoon of Okinawa. Log ship in distress - we responded - US Navy at Naha came up , asked other ship and then us to hold the key down - 500 kcs - and within the minute both ships triangulated by the americans.
I was impressed.
Don't knock old technology.

[El Pinguino]

Originally Posted by Wotname

And there was I thinking the aforementioned half convergency tables were being used to solve this issue.

Is there anything else needed?

https://maritimesa.org/nautical-scie...g-df-bearings/

First I had better correct my spelling while StuM is still abed.
I shall excuse myself on the basis that I wrote it at 0200 just before I did today's Wordle - 2 lines - 30 seconds.
Its 'gnomonic'. simple vid here

https://www.youtube.com/watch?v=nwaWnra-ZSA

I have a paper one of the Sopac somewhere on the boat.
I don't think you could use one to correct RDF bearings.
Half convergency is as shown in your link. The table in Nories is on half a page - very simple.

Essentially you have a great circle bearing of the source and you are correcting that to a rhumb line bearing that you can lay off on your mercator chart.

[flightlead404]

Originally Posted by Sailor Sailor

Have radio direction finders become completely obsolete? Are any aircraft or vessels still using them? Are there still stations transmitting signals?

In the US they've been obsolete for decades. Since the 80's in any aircraft I flew they were used to listen to the ball game to pass the time while enduring the hours and hours of sheer boredom (before the punctuating moment of sheer terror).

[lifeofreilly57]

even when they were current they weren't that accurate, they were subject to atmospheric interference.
I wouldn't use one now.

[flightlead404]

Originally Posted by Chotu

With boats? They are pretty much out of use.

With airplanes however? People still use them.

ILS/GBAS Approach beacons. They guide the plane down using radio direction finders, I believe

mmmmm.....not really.

NDBs used to be, and occasionally still are, part of the approach system. The ILS 20L at KLUK for example used to use Madeira beacon as an initial approach fix. Some of these still remain but have been phased out for years.

En route NDB in CONUS are long gone. Back in the 90's I used to fly to Stella Maria, Long Island, Bahamas following an NDB and I suspect that some of these still remain but doubt anyone really uses it.

ILS/VOR is not really an RDF technology. They use two 180 degree out of phase since waves and calculate the difference as I recall.

[flightlead404]

Originally Posted by thomm225

Sorry RDF's are not obsolete as they are being used to help sailors navigate their way around the world at this moment which to me seems pretty important so they won't like destroy their boats.

Steam Locomotives is a sad example but I guess that is all you can come up with

Just because someone, somewhere is still using a technology doesn't mean its not obsolete.

Some people still use sextants!

[Celestialsailor]

Next, you guys will be telling me SatNav is obsolete.

[Fore and Aft]

CelestialSailor just let me replace the ribbon in my typewriter and I will reply to your question!
Cheers

[carlosproa]

Originally Posted by flightlead404

Just because someone, somewhere is still using a technology doesn't mean its not obsolete.



Some people still use sextants!

About steam locomotives…at high altitude diesel has severe issues with combustion so steam engines are still the norm.

[El Pinguino]

RDF is still used in fox hunting

LF/MF Marine RDF could - despite what has been said - be very accurate in the hands of a skilled operator. The sets being fitted by Japanese shipbuilders from the mid sixties onwards were brilliant.

[Wotname]

Originally Posted by Fore and Aft

CelestialSailor just let me replace the ribbon in my typewriter and I will reply to your question!
Cheers

And to what address are you going to post the typewritten reply?

[Bowdrie]

Back in the early '90s I had one of these.
Paired with the Magnavox Sat-Nav I thought I was in pretty good shape.
Now if only I could get a Sperry Inertial Navigation System along with a Sperry Gyrocompass.

[thomm225]

Originally Posted by flightlead404

Just because someone, somewhere is still using a technology doesn't mean its not obsolete.

Some people still use sextants!

Yep sextants and RDF's are being used for navigation on the GGR 2022 boats.

As a History Major, I enjoy it quite a bit.

Actually my major was History of Technology with a math/computer science minor

Technology meaning interchangeable parts, best time keeping town clock, Henry Ford and Singer Sewing machines (assembly line), best forge coke, .......also Soviet History when they basically moved all factories etc 1,000 miles Eastward before Hitler attacked. The factories were rebuilt and running there but had no shelter or cover so the workers were sometimes working in snow storms but still producing.

Even the early Colt Revolvers all were hand made for years so parts were not interchangeable until later

Suits of armor were only for the rich because poor soldiers couldn't afford the custom build

Rifled barrels was another big innovation.

Roman road technology and aqueduct arches:

The most recognizable feature of Roman aqueducts may be the bridges constructed using rounded stone arches. Some of these can still be seen today traversing European valleys. However, these bridged structures made up only a small portion of the hundreds of kilometers of aqueducts throughout the empire

[Celestialsailor]

Originally Posted by El Pinguino

RDF is still used in fox hunting

LF/MF Marine RDF could - despite what has been said - be very accurate in the hands of a skilled operator. The sets being fitted by Japanese shipbuilders from the mid sixties onwards were brilliant.

Ok...I'll bite...how is RDF used for fox hunting?