"Michael Black" wrote in message
news:alpine.LNX.2.02.1502051950290.19867@darkstar. example.org...
On Thu, 5 Feb 2015, Ralph Mowery wrote:


I don't have any of the very old gear, but every so often I listen to the
hams around 3.85 MHz. that use the old military and AM gear. While I
don't
think it is really legal (and don't really care) some of those AM
transmitters sound beter if I switch to FM on my Icom 746 pro. I think
when
they were made they seem to put out about as much FM as AM.

That's weird. I thought those hardcore AMers wanted purity, and took
effort to ensure they were putting out a good signal. They sure aren't
using modulated oscillators, and I don't think anything where the
modulation would get back to the oscillator.


There may be two kinds of people using AM. One for 'good quality AM' ,but
the other is using mainly the military gear from around the WW2 era or so.
Maybe even before that if they can find it. That is the stuff that can
contain about as much FM as it does AM. The power supplies are often
feeding the oscillator as well as the final stages and not regulated very
well if at all. That probably helps modulate the transmitter to have a lot
of FM in the signal.

"Ralph Mowery" wrote in message
...
"Michael Black" wrote in message
news:alpine.LNX.2.02.1502051950290.19867@darkstar. example.org...
On Thu, 5 Feb 2015, Ralph Mowery wrote:
I don't have any of the very old gear, but every so often I listen to
the
hams around 3.85 MHz. that use the old military and AM gear. While I
don't think it is really legal (and don't really care) some of those AM
transmitters sound beter if I switch to FM on my Icom 746 pro. I think
when they were made they seem to put out about as much FM as AM.

That's weird. I thought those hardcore AMers wanted purity, and took
effort to ensure they were putting out a good signal. They sure aren't
using modulated oscillators, and I don't think anything where the
modulation would get back to the oscillator.

There may be two kinds of people using AM. One for 'good quality AM' ,but
the other is using mainly the military gear from around the WW2 era or so.
Maybe even before that if they can find it. That is the stuff that can
contain about as much FM as it does AM. The power supplies are often
feeding the oscillator as well as the final stages and not regulated very
well if at all. That probably helps modulate the transmitter to have a
lot of FM in the signal.

FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.
--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk

FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

Jeff

In message , Jeff writes

FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

In those days, some AM transmissions had quite a lot of FM on them!

10m FM works well using modified CB sets (2.5kHz deviation and 10kHz
channel spacing). It slope fairly well using my Eton SW receiver with
the AM filter switched to 'narrow'.
--
Ian

"Jeff" wrote in message ...
FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

Jeff

When was FM first invented? BBC broadcast FM started in 1955.
--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk

On 06/02/2015 14:47, FranK Turner-Smith G3VKI wrote:
"Jeff" wrote in message ...
FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

Jeff

When was FM first invented? BBC broadcast FM started in 1955.

http://en.wikipedia.org/wiki/Edwin_Howard_Armstrong

In message , Jeefaw K. Effkay
writes
On 06/02/2015 14:47, FranK Turner-Smith G3VKI wrote:
"Jeff" wrote in message ...
FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

Jeff

When was FM first invented? BBC broadcast FM started in 1955.

http://en.wikipedia.org/wiki/Edwin_Howard_Armstrong

I told you Google would tell us.
--
Ian

In message , FranK Turner-Smith G3VKI
writes
"Jeff" wrote in message ...
FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.
Well perhaps not 'always'. FM was not allowed prior to about 1952.
Jeff

When was FM first invented? BBC broadcast FM started in 1955.

The Murkins were trying it (for broadcast) in the early 40s (Google will
tell us).
--
Ian

On 06/02/15 12:39, Jeff wrote:

FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

There was an adaptation of the WS19 (I think it was the WS32) that used
FM instead of AM, to test the use of FM on the battlefield. I guess it
was unsuccessful or other considerations mitigated against it, because
it wasn't adopted in that form, but some manpack sets and WS19 candidate
replacements were FM. I think that only about 100 WS32 were made.


--
Spike

"Hard cases, it has frequently been observed, are apt to introduce bad
law". Judge Rolfe

"Spike" wrote in message
...
On 06/02/15 12:39, Jeff wrote:
FM has always been a legal mode for 80m in the UK, it's just that nobody
normally uses it intentionally.
Provided you're using no more bandwidth than normal AM I can't see a
problem.

Well perhaps not 'always'. FM was not allowed prior to about 1952.

There was an adaptation of the WS19 (I think it was the WS32) that used FM
instead of AM, to test the use of FM on the battlefield. I guess it was
unsuccessful or other considerations mitigated against it, because it
wasn't adopted in that form, but some manpack sets and WS19 candidate
replacements were FM. I think that only about 100 WS32 were made.

To ensure compatibility it would have been necessary to swap all the
military AM radios to FM at the same time.
The middle of a global war is not the time to make changes on that scale,
especially as the advantages of doing so seem minimal.
--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk