WW2 Radio Compass
 

You hear that,boys? he's a copper,a dirty lousy copper! James Cagney.
Who threw my Palm Tree over the side?
cuhulin

WW2 Radio Compass
 

"Brad" (bradvk2qq AT w6ir.com) writes:


Since the newsgroup is r.r.shortwave, then DF'ing shortwave seems to me to
be the topic. Here is another method worth trying, particularly because of
it's compact size. http://www.qsl.net/dj3tz/loop1.html

And a significant point is that a "radio compass" was so simple, because
it was at a time when applications for radio was relatively small. The
more complicated systems came later, when things had built up and a
need for something better came along.

Direction finding has come to mean tracking down an unknown station, but
in the case of a Radio Compass the scheme is identical, using a directional
antenna and a basic receiver, but you pick a station you know the location
of, so when you point to it you know you are going the right direction
(unless you pick the wrong side of the null, and go 180 degrees in
the wrong direction, but there were ways of fixing that).

While there were beacon stations set up for Radio COmpass use, I gather
it was not uncommon to use existing broadcast stations for the purpose.

Were talking sixty to seventy years ago when they first started using
Radio Compasses.

Michael

WW2 Radio Compass
 

"Michael Black" wrote in message
...

"Brad" (bradvk2qq AT w6ir.com) writes:


Since the newsgroup is r.r.shortwave, then DF'ing shortwave seems to me
to
be the topic. Here is another method worth trying, particularly because
of
it's compact size. http://www.qsl.net/dj3tz/loop1.html

And a significant point is that a "radio compass" was so simple, because
it was at a time when applications for radio was relatively small. The
more complicated systems came later, when things had built up and a
need for something better came along.

Direction finding has come to mean tracking down an unknown station, but
in the case of a Radio Compass the scheme is identical, using a
directional
antenna and a basic receiver, but you pick a station you know the location
of, so when you point to it you know you are going the right direction
(unless you pick the wrong side of the null, and go 180 degrees in
the wrong direction, but there were ways of fixing that).

While there were beacon stations set up for Radio COmpass use, I gather
it was not uncommon to use existing broadcast stations for the purpose.

Were talking sixty to seventy years ago when they first started using
Radio Compasses.

Michael

That's right. A Radio compass is like DF'ing in reverse. I know where you
are, so where am I?
ADF is still an approved and popular form of aircraft navigation. The VLF
beacons are maintained for that purpose.

Whilst broadcast stations were also used for navigation, it was not really a
recomended practice. The radiation pattern could change, but more
importantly, without a proper identification, it was possible to DF on the
wrong transmitter, sharing the same frequency. If they carried the same
music program, there may be no way to know until the pilot is truly lost.
That said, the ABC station near us is called 2RN and is the inbound
checkpoint. That's mostly because it is a big thing with flashing lights.

Where is SR located? If he tells us his home town or local airport, we'll
find a beacon for him to practice on.

Brad.

WW2 Radio Compass
 

Brad I am in Queens New York. Sometimes I like to find beacons when
nothing else is on the band.

Within my 10-20 or so radius area their are two big air port and not far
from the Atlantic. I noice that on the upper part of the medium band I
sometimes pick up a CW beacon. I belive it's a beacon because it
repeats it's self in perfect timming. I had not yet decoded the message
yet.

Now, MFJ sell an interesting device, it's looks like a black flat box
with numbers and red lights on them. The device is suppose to read all
beacons nation wide.

Do you know anything about that? And how does this work? And is WWV
that voice that gives the UTC on 10000.0 MHZ?

73 SR!



Brad wrote:

"Michael Black" wrote in message
...

"Brad" (bradvk2qq AT w6ir.com) writes:



Since the newsgroup is r.r.shortwave, then DF'ing shortwave seems to me
to
be the topic. Here is another method worth trying, particularly because
of
it's compact size. http://www.qsl.net/dj3tz/loop1.html

And a significant point is that a "radio compass" was so simple, because
it was at a time when applications for radio was relatively small. The
more complicated systems came later, when things had built up and a
need for something better came along.

Direction finding has come to mean tracking down an unknown station, but
in the case of a Radio Compass the scheme is identical, using a
directional
antenna and a basic receiver, but you pick a station you know the location
of, so when you point to it you know you are going the right direction
(unless you pick the wrong side of the null, and go 180 degrees in
the wrong direction, but there were ways of fixing that).

While there were beacon stations set up for Radio COmpass use, I gather
it was not uncommon to use existing broadcast stations for the purpose.

Were talking sixty to seventy years ago when they first started using
Radio Compasses.

Michael


That's right. A Radio compass is like DF'ing in reverse. I know where you
are, so where am I?
ADF is still an approved and popular form of aircraft navigation. The VLF
beacons are maintained for that purpose.

Whilst broadcast stations were also used for navigation, it was not really a
recomended practice. The radiation pattern could change, but more
importantly, without a proper identification, it was possible to DF on the
wrong transmitter, sharing the same frequency. If they carried the same
music program, there may be no way to know until the pilot is truly lost.
That said, the ABC station near us is called 2RN and is the inbound
checkpoint. That's mostly because it is a big thing with flashing lights.

Where is SR located? If he tells us his home town or local airport, we'll
find a beacon for him to practice on.

Brad.

WW2 Radio Compass
 

"SR" wrote in message
...
Brad I am in Queens New York. Sometimes I like to find beacons when
nothing else is on the band.

Within my 10-20 or so radius area their are two big air port and not far
from the Atlantic. I noice that on the upper part of the medium band I
sometimes pick up a CW beacon. I belive it's a beacon because it repeats
it's self in perfect timming. I had not yet decoded the message yet.

Now, MFJ sell an interesting device, it's looks like a black flat box with
numbers and red lights on them. The device is suppose to read all beacons
nation wide.

Do you know anything about that? And how does this work? And is WWV that
voice that gives the UTC on 10000.0 MHZ?

73 SR!

The Lady on 10MHz is in Hawaii (WWVH), the Man is Ft Collins (WWV). I think
the calls are correct. Mostly I hear WWVH and JJY (Japan). Listen around the
1/4 hour marks for an ident. I can hear both WWV's tonight. 30m is open to
the USA. Unfortunately it is also being jammed by a bunch of Asian pirates
yakking on the same frequency.

The morse code ident on the aircraft beacons is slow enough for you to
decipher it one character at a time. You can then go to airnav.com and enter
the callsign into their search engine and it should come up with some place
local to you.

Take Flushing for an example, they even spell out the Morse for you:

NDB name Hdg/Dist Freq Var ID
BRIDGE 022/12.9 414 12W OGY --- --. -.--
PATERSON 137/17.6 347 12W PNJ .--. -. .---
BABYLON 301/21.4 275 14W BBN -... -... -.
CHATHAM 096/27.2 254 11W CAT -.-. .- -



On a nice quiet winters night I was testing an aircraft ADF and trying to
point to a station about 100km south. The needle was flicking back and forth
between south and north. When I decoded the mixture of callsigns, instead of
SLS (shelleys) I came up with LRE (Longreach.)

Longreach is in northern Queensland and about 1800km away. Now that's not
bad DX with a ferrite antenna at 12" off the ground!

I'm not familiar with the MFJ device. Is it a CW Code Reader of some sort?

By the way, the beacon at the top of the MW band is more likely to be a
Marine beacon. I have no experience with them, but Google is your friend.
There are some Marine beacons at VLF, but most are aircraft.

Let's see, it must be 12 years since I was last in Queens. Wow, time sure
flies.

Brad.

WW2 Radio Compass
 

UHF DF certainly has some applications, particularly if DX'ing FM broadcast
stations, but so would a yagi and a rotator.

It's also useful for homing on UHF NDBs. Pretty hard to put a Yagi and rotator
on a Navy aircraft.

Dave

WW2 Radio Compass
 

Hmm we used BC DFing all the time on Pacific overseas flights -- Navy --
Korean War
But LORAN Also
--
CL -- I doubt, therefore I might be !






"Cmdr Buzz Corey" wrote in message
...
Brad wrote:


Whilst broadcast stations were also used for navigation, it was not
really a recomended practice. The radiation pattern could change,


Doesn't matter if the radiation pattern changes, if you can still receive
the signal you still know the direction.

WW2 Radio Compass
 

LORAN is ultra low frequency,,, isn't it?
cuhulin

WW2 Radio Compass
 

You can look at the Sun and Stars and tell which way is South and West
and East and North.
cuhulin

WW2 Radio Compass
 

We did that too -- our transport planes (Super Connies) had a bubble on top
of the cabin -- the navigator was required to periodically use a sextant --
US NAVY VR-8 Korean War

--
CL -- I doubt, therefore I might be !

wrote in message
...
You can look at the Sun and Stars and tell which way is South and West
and East and North.
cuhulin