Digital radio switchover gets poor reception

In article , Steve Terry
scribeth thus
"tony sayer" wrote in message
...
In article , Steve Terry
scribeth thus
"tony sayer" wrote in message
...
In article , Steve Terry
scribeth thus
"tony sayer" wrote in message
...
In article , charles
scribeth thus
In article ,
Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
snip
FWIW Band 1 has hardly any PMR thereon due to the absurdly long
aerials
required, the impossibility of using portables and the lack of type
approved equipment/s..

Wot like this?
http://www.doubleradius.com/Motorola...dio-35-50-MHz-
Lowband-16-Channel

35 to 50MHz is heavily used in the US especially by police depts,
just not here.

No there not at all efficient even at 77 odd MHz theres no comparison
with a VHF hi band portable on say 170 MHz.

Lowband handheld to handheld maybe because of poor groundplain and erp
at both ends. But lowband handheld to lowband mobile or base will beat
highband handheld to mobile or base everytime.

Can you explain that in a bit more detail as if you read it carefully it
doesn't make sense..


Will it now. Well in 25 years of PMR operation and trailing this its
always proved to be the other way round. Even a research consultancy we
know of not a million miles from here was commissioned to arbitrate for
a large council who were sold a Low band system with handportables and
it was very problematical in that the range was very poor indeed and in
the end the supplier had to pay for them to use VHF Hi Band!...

If its as good as you claim can you name perhaps apart from Motorola
anyone selling Low band portables , well more than a handful per annum
in the UK?..


Lets just say you have experience of lowband VHF as it's used in the UK,
whereas i have a more international experience of it's use.


So how does that change the laws of physics and electromagnetic
proprogation please?...

Steve Terry

--
Tony Sayer

In article [email protected], Woody
scribeth thus
"tony sayer" wrote in message
...
In article [email protected], Woody
scribeth thus
"tony sayer" wrote in message
...
In article

.com,
scribeth
thus
On Jun 2, 10:57 pm, tony sayer wrote:
In article [email protected], Woody
scribeth thus

"Dave Plowman (News)" wrote in
message
...
In article [email protected],
Woody wrote:
Band 1 has never been used for TV in the UK.

Eh?

--
Sorry, senior moment. Should have read '...never been used
for
PMR in the UK.'

Has .. but very limited use but darn sarff, and IIRC now
fallen out of
favour...
--
Tony Sayer

Wouldn't all that PMR stuff just above the old ch B5 be
within
Band
I?

Bill

Well Band 1 is up to 68 MHz and what's called VHF Low band is
from 68 to
88 MHz. The lowest in current use in Low band data which is
usually 68
mobile TX and 81/2 base Tx but these are quite few and far
between...

--
Tony Sayer




Wasn't it the other way around Tony?

The original pairings of E-band were

That's Pye talk)..

85 base Tx with mobile Tx 13.5MHz lower (such as the AA)

Yes..

87 base Tx with mobile Tx 10MHz lower (such as the RAC)

Yes..

Some single frequency working around 86MHz.

Very little .. at one time that frequency was allocated to IBA
aerial
riggers;!..

In earlier days the Police (P-band) had base Rx around 79-82MHz

With TX around 101-etc

Then the wonders of the RA and WARC came along and plonked Fire
Tx around 71-72MHz with receive somewhat variant in the
80-84MHz
area.

OK..

Som
ehow I doubt 68MHz would have been a viable base receive
frequency with 100W+ transmitters only a meg or two away.

Well 68 the low side is used for mobile receive..

I may be wrong as I know I only ever worked on one 68/81MHz
system (13.5MHz spacing) but I have a fair certainty that it
was
base TX low.

Other way round all the ones I've seen but then again thats not
that
many..

The Fire brigades have now gone to Airwave round this area so
all rather
academic now....



--
Tony Sayer



Agreed, but an interesting discussion nonetheless?



As always...



--
Tony Sayer

In article ,
tony sayer wrote:
Just dragging it back to broadcast there are some Audio point to point
and Talkback links in there around 48 to 52 MHz odd..

BBC Lime Grove used Band 1 for studio talkback a long time ago - you could
pick it up on an ordinary TV receiver if you lived locally.

--
*Where there's a will, I want to be in it.

Dave Plowman London SW
To e-mail, change noise into sound.

MB wrote:




We used 47 MHz at one time, the aerials were not particularly "absurd",
range was great most of the time though we used to get interference from
Russian fishing boats sometimes. Pye Westminsters were used.

Other low VHF frequencies have been used for PMR at times.






I sem to remember the old Mullard Music links in OBs were 46.8Mc/s.
The sleeve dipoles were a bit big though.
(nice Telcon RF connectors though - remember those?)

Mike

Dave Plowman (News) wrote:
In article ,
tony sayer wrote:

Just dragging it back to broadcast there are some Audio point to point
and Talkback links in there around 48 to 52 MHz odd..


BBC Lime Grove used Band 1 for studio talkback a long time ago - you could
pick it up on an ordinary TV receiver if you lived locally.


And of course OBs used frequencies like 93.1 92.4 for talkback regularly
We had upset callers around boat race time when prod talkback could be
happily received all down the river and included various unedited words
from production!

Mike