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-   -   What DF is DF? (http://www.bikeforums.net/general-cycling-discussion/108488-what-df-df.html)

JenM 05-21-05 08:53 AM

What DF is DF?
 
I can't figure out what it stands for. Thanks. :rolleyes:

Moonshot 05-21-05 09:52 AM

Can you use it in a sentence?

Nightshade 05-21-05 10:09 AM

lame.....real lame......

Dr. Moto 05-21-05 10:25 AM

Divorced Female?

Trsnrtr 05-21-05 11:57 AM

Quote:

Originally Posted by JenM
I can't figure out what it stands for. Thanks. :rolleyes:

It stands for Diamond Frame and is shorthand that recumbentists use for wedgies, oops, I mean upright bikes.

JenM 05-22-05 01:25 AM

Quote:

Originally Posted by Tightwad
lame.....real lame......

What? That I asked an honest question?

lilHinault 05-22-05 02:37 AM

Diamond Frame... heh. I didn't know either!

I"m used to DF = Direction Find, as in radio transmitting, finding a transmitter.

khuon 05-22-05 02:42 AM

Quote:

Originally Posted by lilHinault
Diamond Frame... heh. I didn't know either!

I"m used to DF = Direction Find, as in radio transmitting, finding a transmitter.

As in an ADF... ;)

I took DF to mean "don't fragment". :D

Okay, so I actually knew that DF meant diamond frame but I just like being a smarta$$.

lilHinault 05-22-05 03:55 AM

ADF = automatic DF, like your basic doppler set does to find that @#$%@#$% fox....

CommuterRun 05-22-05 05:25 AM

DF-Diamond Frame. Well, that's the one thing I learned new for today. Met my quota. ;)

I'm vaguely familiar with RDF. We used to use it for navigation when we went off-shore, fishing. This was back before LORAN A. Does that date me? ;)

khuon 05-22-05 11:58 AM

Quote:

Originally Posted by CommuterRun
I'm vaguely familiar with RDF. We used to use it for navigation when we went off-shore, fishing. This was back before LORAN A. Does that date me? ;)

Radio Direction Finder? In aviation we used ADFs (automatic direction finders) which would basically lock onto an NDB (non-directional beacon)... essentially any omni-directional AM transmitter including radio station towers. The NDBs used were fixed and marked on maps. A lot of times one would use the approach marker beacons... usually the LOM (locator outer marker). The ADF was a very complicated and expensive piece of hardware mainly because of the mechanics and installation. It was big and heavy too. The nice thing about ADF/NDBs is that the technology and principles of operation are fairly robust. However, the skills required to execute an NDB approach were fairly tough to master and one of the most dreaded things during IFR training... especially if one had to do it with a non-slaved CDI/HSI (course deviation indicator/horizontal situation indicator) because you have to cross reference across two different instrument displays to determine your radial position. The ADF is used along with a DME (distance measuring equipment) to determine your location from the beacon. Another benefit of ADF/DME equipment is for use in SAR operations to locate ELTs (emergency locator transmitters).

sukispop 05-22-05 12:13 PM

Quote:

Originally Posted by Tightwad
lame.....real lame......

I'll tell you what "real lame" is--

It's when a forums member can't find the common decency or courtesy to give a simple and friendly answer to a sincere and friendly question.


The next time that you find a member's question lame...real lame....why don't you do us all a favor, and pass on posting any kind of reply, and keep your nastiness to yourself?

:mad:

operator 05-22-05 01:14 PM

Quote:

Originally Posted by sukispop
I'll tell you what "real lame" is--

It's when a forums member can't find the common decency or courtesy to give a simple and friendly answer to a sincere and friendly question.


The next time that you find a member's question lame...real lame....why don't you do us all a favor, and pass on posting any kind of reply, and keep your nastiness to yourself?

:mad:

Don't worry about him, that guy is an accredited forum troll. Press ignore.

sukispop 05-22-05 01:55 PM

Quote:

Originally Posted by operator
Don't worry about him, that guy is an accredited forum troll. Press ignore.

Thanks for the info, operator!

'Just more evidence that God must have had a migraine when he created trolls....

;)

CommuterRun 05-22-05 02:38 PM

The RDF we had worked like the ADF you describe, Khuon, except everything was manual. The base of the unit had to be oriented to north, then rotate a knob to align the directional antennae with the signal you wanted to pick up, an indictator needle aligned with the antennae pointed out the direction to the signal on a compass rose printed on the base of the unit. Plot this azimuth on a chart then do it all again with a different signal. Where the two lines crossed was our location. Funny how cutting-edge stuff back then sounds pretty crude now, but remember, this was back when a computer took up an entire large room and a thing that was to be called a PC was still quite a few years away. Heck, there were even real Hippies still around back then. ;)

We kept using this unit through the LORAN A years and later switched to LORAN C. After loosing the boat to a hurricane many years ago, and later Grandpa to cancer, none of us fish offshore anymore. These days my Dad, brothers and I pretty much stick to inshore and freshwater and like everybody else, we use GPS.

Don't know whatever happened to that old RDF unit. Wish I still had it.

lilHinault 05-22-05 03:33 PM

ADF's been around a long time, the Japanese planes that bombed Pearl Harbor used radio station KGMB in Honolulu as a signal to DF coming in.......

check out "radiosport" it's a modern, fun "sport" where you use a directional VHF antenna to DF and find a "fox" or hidden transmitter.

JenM 05-22-05 08:16 PM

It's good to know not all DF riders have a stick up their _ _ _ _!

khuon 05-22-05 10:14 PM

Quote:

Originally Posted by lilHinault
ADF's been around a long time, the Japanese planes that bombed Pearl Harbor used radio station KGMB in Honolulu as a signal to DF coming in.......

You might be surprised to find that many things in aviation are actually quite old and "antiquated" technology. For instance, many light aircraft engines are basically a high-powered equivalents of lawn mower engines. Fuel injection? Electronic ignition? Not in those Cessna 172s flying out of PAO. We're talking good old carbs and magnetos. The advantage however is that if you have a total electrical system failure, the engine will continue to run.

azesty 05-22-05 10:39 PM

I have done underwater tracking of Leafy Seadragons. Radio, except for very long wavelengths, wont work in salt water, so we had to use sonic tags, and a manual directional microphone pointing technique. Not that old, but different.

a

khuon 05-22-05 10:44 PM

Quote:

Originally Posted by azesty
we had to use sonic tags, and a manual directional microphone pointing technique. Not that old, but different.

Hydrophones have been around a long time too. ;)

lilHinault 05-22-05 11:00 PM

Morse Code.

dm_fuel100 05-22-05 11:05 PM

Quote:

Originally Posted by Trsnrtr
It stands for Diamond Frame and is shorthand that recumbentists use for wedgies, oops, I mean upright bikes.

Diamond Frame? Huh, and all this time I thought they were my initials. :rolleyes:

Juha 05-25-05 04:34 AM

Quote:

Originally Posted by CommuterRun
Funny how cutting-edge stuff back then sounds pretty crude now, but remember, this was back when a computer took up an entire large room and a thing that was to be called a PC was still quite a few years away. Heck, there were even real Hippies still around back then. ;)

OK, I'll reluctantly buy the stuff about computers. But what are these Hippies you claim to have seen? :D

--J

eubi 05-25-05 08:48 AM

Quote:

Originally Posted by lilHinault
Morse Code.

If we're talking HAM lingo, Morse Code is "CW" (Continuous Wave).

KG6NPA

jsharr 05-25-05 10:00 AM

Quote:

Originally Posted by Juha
OK, I'll reluctantly buy the stuff about computers. But what are these Hippies you claim to have seen? :D

--J

I think the alledged "hippies" were just a hallucination brought on by some bad shrooms.


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