OT Farthest VHF UHF reception:

[callsignzippo]

you may recall before the age of sat links, uplink, downlink repeaters
etc. If you care to respond I would be interested in wx conditions
and location at the time.

Thanks
Rico

[Leadfoot]

"callsignzippo" > wrote in message
om...
> you may recall before the age of sat links, uplink, downlink repeaters
> etc. If you care to respond I would be interested in wx conditions
> and location at the time.

I was in the Williams AFB (30M SE Phoenix AZ) WX shack working on a DL-19W
Fax machine when the Det commander told me he was talking to a T-38 40K over
Blythe CA. About 165 miles, a little static but clear. Freq 344.6MHZ Single
channel GRT-22 with 50W power amp, standard mil UHF umbrella antenna on a 40
foot tower call it 1978 or thereabouts. I don't think the ARC-164 had been
installed at that time on the T-38's. I don't recall WX conditions

I doubt this will be a record as I had a Captain who was RIF'D back to TSGT
as a Radio shop supervisor who said the NSA UHF antennas in Pakistan were
picking up US Fighter missions over Vietnam. Claimed they were blabbing
loads of classified information but that trying to get scramblers to work on
fighter at that time was next to impossible.

>
> Thanks
> Rico

[Dave Kearton]

"callsignzippo" > wrote in message
om...
| you may recall before the age of sat links, uplink, downlink repeaters
| etc. If you care to respond I would be interested in wx conditions
| and location at the time.
|
| Thanks
| Rico



I joined the Australian Army in '77, so my info is all second hand.

Had a range instructor who told me that he was 'politely' asked to select
another frequency as he was interrupting an air strike on Hue. He
believed it must have been USN because of the frequent and creative use of
the word '****'.
Period would have been '69 and location was central NSW, distance of a
couple of thousand km with a PRC 25 set.


Different officer, different time told me of regular (almost daily)
conversations from Darwin to the Australian Task Force at Nui Dat. Same
period and the duration was about 10 minutes each evening from about 1600.
I'm guessing a PRC 25 or 77 as this officer was a grunt at the time (not
that there's anything wrong with that)





Cheers


Dave Kearton

[Dave Kearton]

|
| I joined the Australian Army in '77, so my info is all second hand.
|


Dammit, that should have read '75. They told me that my eyesight
should go first.




Cheers


Dave Kearton

[Krztalizer]

>
>I joined the Australian Army in '77, so my info is all second hand.

good enough.

<snip long distance story>

I was going to chime in earlier that ducting caused some really odd experiences
with our friend, the electromagnetic spectrum. Some conditions in the North
Arabian Sea caused our radar to be so reduced in ability that it could not see
more than a thousand yards - but after climbing to a particular altitude, we
found ducting conditions where we were in radio contact with ships hundreds of
miles out. Radio wave propogation is a funny thing..

yfG

[Krztalizer]

>
>| I joined the Australian Army in '77, so my info is all second hand.
>|
>
>
>Dammit, that should have read '75. They told me that my eyesight
>should go first.
>

They told me the first thing to go would be
They told me the first thing to go waaa
They told me the first thinnnngg
They told me theffff
GARP
arp.

[Kevin Brooks]

"Krztalizer" > wrote in message
...
> >
> >I joined the Australian Army in '77, so my info is all second hand.
>
> good enough.
>
> <snip long distance story>
>
> I was going to chime in earlier that ducting caused some really odd
experiences
> with our friend, the electromagnetic spectrum. Some conditions in the
North
> Arabian Sea caused our radar to be so reduced in ability that it could not
see
> more than a thousand yards - but after climbing to a particular altitude,
we
> found ducting conditions where we were in radio contact with ships
hundreds of
> miles out. Radio wave propogation is a funny thing..

Indeed. Using a standard AN/VRC-92 SINCGARS radio with a whip antenna, we
made contact with Fort Sill Range Control from the southwestern area of
Virgina, a distance of about one thousand miles (of course, we were trying
to contact our BN HQ about fifteen miles distant with absolutely no luck due
to terrain). They were initially rather ticked at our stepping on their net
(until I explained where we were transmitting from, which garnered the
incredulous response, "You mean Virginia, as in the STATE?"). Strangely
enough, the next time we hit that frequency (ISTR we were on a ten day
rotation of freqs), we did it again. Not bad for a radio that is supposed to
have a normal max range of twenty or thirty miles!

Brooks

>
> yfG

[[email protected]]

"Kevin Brooks" > wrote:

> They were initially rather ticked at our stepping on their net
>(until I explained where we were transmitting from, which garnered the
>incredulous response, "You mean Virginia, as in the STATE?"). Strangely
>enough, the next time we hit that frequency (ISTR we were on a ten day
>rotation of freqs), we did it again. Not bad for a radio that is supposed to
>have a normal max range of twenty or thirty miles!
>
>Brooks
>

Yes, this happens quite frequently (sorry!) on 'ham radio'.

On one of our popular VHF bands (145. mHz) where many repeaters
live we see it quite often in the spring and fall. Distances of 2
- 3 and sometimes 4 thousand miles is fairly common. It's called
(as Gordon mentioned) 'ducting'. Similar to Radio Waves being
reflected back down to earth by the ionosphere which normally
allows VHF Radio Waves to pass through it and become lost while
at the same time reflecting lower frequency (HF) waves back to
earth.

This is why some frequencies are better at long distances than
others...and why conditions change from day to day...season to
season...
--

-Gord.

[Yeff]

On Mon, 01 Mar 2004 21:40:15 GMT, Gord wrote:

> This is why some frequencies are better at long distances than
> others...and why conditions change from day to day...season to
> season...

....day to night.

-Jeff B.
yeff at erols dot com

[Jim Atkins]

This isn't UHF/VHF, but when I first moved to Arizona, I was living in
Prescott, NW of Phoenix up in the mountains. I was going to the store very
early in the morning. I hit the scan button on the radio and got a weather
report that sounded like they were piping in blizzards and polar bears
direct from the Yukon. Turns out I was getting a station from Norfolk,
Nebraska. I was just slightly relieved.

--
Jim Atkins
Twentynine Palms, CA USA

Outside of a dog, a book is man's best friend.
Inside of a dog, it's too dark to read.
-Groucho Marx

[[email protected]]

Yeff > wrote:

>On Mon, 01 Mar 2004 21:40:15 GMT, Gord wrote:
>
>> This is why some frequencies are better at long distances than
>> others...and why conditions change from day to day...season to
>> season...
>
>...day to night.
>

For sure...
--

-Gord.

[WaltBJ]

Can't cite an specific example but 'moon-bounce' was first achieved
not too long after 1950. Also, meteor trails can reflect all VHF-plus
signals including TV and FM. Any time you get a momentary reception of
a strange signal it is probably a bounce from such a trail or from a
high altitude airplane. We can get Colorado Springs TV stations from
airplane bounce here 65 miles north of Denver.
Walt BJ

[Tex Houston]

"WaltBJ" > wrote in message
m...
> Can't cite an specific example but 'moon-bounce' was first achieved
> not too long after 1950. Also, meteor trails can reflect all VHF-plus
> signals including TV and FM. Any time you get a momentary reception of
> a strange signal it is probably a bounce from such a trail or from a
> high altitude airplane. We can get Colorado Springs TV stations from
> airplane bounce here 65 miles north of Denver.
> Walt BJ

Walt,

Part of that is the location of station antennas on Cheyenne Mountain,
9500'+ but of course most of it is propagation which is why it is art, not
science. I was in my apartment in Spokane Washington once and while
switching TV channels noticed a picture on an unused channel. No sound but
I started watching and the Station break revealed I had just watched about
20 minutes from Waco Texas.

The best I have done on the VHF hamband is getting an answer from a farmer
in his tractor cab in Sidney Nebraska on a local repeater frequency. I was
bringing up both the local repeater and the one in Sidney.

Regards,

Tex Houston

[John Hairell]

On 1 Mar 2004 18:17:14 -0800, (WaltBJ) wrote:

>Can't cite an specific example but 'moon-bounce' was first achieved
>not too long after 1950. Also, meteor trails can reflect all VHF-plus
>signals including TV and FM. Any time you get a momentary reception of
>a strange signal it is probably a bounce from such a trail or from a
>high altitude airplane. We can get Colorado Springs TV stations from
>airplane bounce here 65 miles north of Denver.
>Walt BJ

Some US Army ATC units in Vietnam were occasionally able to talk
(using relatively short-range radios, i.e. 20-30 nm) to similar units
in South Korea, about 2200 miles away. I've talked to aircraft via
tactical radios supposedly limited to "line-of-sight" and the aircraft
were around 250 miles away.

John Hairell )