John Ferrell wrote:

Cecil Moore wrote:
The audio is not mixed with the main carrier?

It can be either way.

If you choose to use separate transmitters the demands on antenna
bandwidth are greatly reduced.
John Ferrell W8CCW

Thanks John, my IC-706 will receive the TV frequencies, but since
I have never heard any audio, I assumed the audio and video were
mixed to an IF frequency and then mixed to the TV frequency. (I
have a reference book on TV but haven't looked at it in a long
time).
--
73, Cecil http://www.qsl.net/w5dxp

No. They are separate. Audio is FM and video is AM. Dan

Cecil Moore wrote:
John Ferrell wrote:

Cecil Moore wrote:

The audio is not mixed with the main carrier?


It can be either way.

If you choose to use separate transmitters the demands on antenna
bandwidth are greatly reduced. John Ferrell W8CCW


Thanks John, my IC-706 will receive the TV frequencies, but since
I have never heard any audio, I assumed the audio and video were
mixed to an IF frequency and then mixed to the TV frequency. (I
have a reference book on TV but haven't looked at it in a long
time).

dansawyeror wrote:
No. They are separate. Audio is FM and video is AM. Dan

I can receive the commercial FM band just fine on my IC-706.
Why can't I receive TV audio on it?
--
73, Cecil http://www.qsl.net/w5dxp

If the meter is misapplied, it's misapplied. If my transmitter is
designed to operate optimally into a 300 ohm load and I use an "SWR"
meter calibrated to 50 ohms, it's not going to do any better job
indicating proper transmitter matching than indicating SWR on a 300 ohm
line.

I will continue happily to call my SWR meter an SWR meter, and know
enough about what's going on inside it to apply it
appropriately--whether it's to the task of giving me an indication of
SWR on a transmission line or the task of indicating proper loading on
a source.

I suppose there are many who will continue to happily call them SWR
meters and NOT understand how to properly apply them. I'd much rather
work on educating them to understand how the meter works and how to
apply it properly than to insist they call it by some other name. I've
been at the task since B.R.E.

But of course, not everyone sees it that way.

Cheers--and Merry Christmas,
Tom

You can if you tune to the audio offset.

"Cecil Moore" wrote in message
t...
dansawyeror wrote:
No. They are separate. Audio is FM and video is AM. Dan

I can receive the commercial FM band just fine on my IC-706.
Why can't I receive TV audio on it?
--
73, Cecil http://www.qsl.net/w5dxp

On Sun, 25 Dec 2005 22:59:49 -0500, "Fred W4JLE"
wrote:

You can if you tune to the audio offset.

"Cecil Moore" wrote in message
et...
dansawyeror wrote:
No. They are separate. Audio is FM and video is AM. Dan

I can receive the commercial FM band just fine on my IC-706.
Why can't I receive TV audio on it?

Fred, is the correct answer because although analogue TV sound in
frequency modulated on a sub carrier of the composite signal, the sub
carrier is not transmitted in the "commercial FM band".

Cecil's IC-706 may not cover the entire TV broadcast bands, he only
asked why, when he can receive the commercial fm band just fine, can
he not receive TV sound in general.

Cecil probably knows the answer.

Owen

--
73, Cecil http://www.qsl.net/w5dxp

--

Fred W4JLE wrote:
You can if you tune to the audio offset.

I have run the IC-706 all up and down the channel 3
60-66 MHz frequencies while in College Station, TX
and cannot hear the audio anywhere.
--
73, Cecil http://www.qsl.net/w5dxp

Owen Duffy wrote:
Cecil probably knows the answer.

Actually, I don't. My IC-706 certainly covers 60-66 MHz which
is channel 3 in College Station, TX. I jumped to the conclusion
that since I couldn't hear WFM audio anywhere on that band, that
the audio wasn't detectable until down-converted to the
intercarrier. It is possible that I hit some dead air time and
gave up too soon.

I just cracked open my TV reference book and it indicates there
are two ways to detect the sound, split IF reception and intercarrier
reception. What now seems most likely is that I didn't tune high
enough up to the 65.75 MHz sound carrier frequency or if I did
tune that high, I hit some dead air time with no modulation.

Next time I'm over there, I will try again.
--
73, Cecil http://www.qsl.net/w5dxp

On Mon, 26 Dec 2005 06:06:08 GMT, Cecil Moore wrote:

Fred W4JLE wrote:
You can if you tune to the audio offset.

I have run the IC-706 all up and down the channel 3
60-66 MHz frequencies while in College Station, TX
and cannot hear the audio anywhere.

Is the sound subcarrier supposed to be at 65.75MHz for your Ch3?
--

In article ,
Cecil Moore wrote:

I have run the IC-706 all up and down the channel 3
60-66 MHz frequencies while in College Station, TX
and cannot hear the audio anywhere.

For what it's worth, I'm able to use my Kenwood TS-2000 to tune in the
audio carrier of our local Channel 2 station. According to my cheat
sheet, 2's video carrier is at 55.25, with audio carrier 4.5 MHz
higher... hence 59.75 MHz. It seems to tune in best on my radio at
59.745.

Your channel 3 audio carrier ought to be at 61.25 + 4.5 = 65.75 MHz.

I don't have my service monitor handy so I can't tell for certain what
the peak FM carrier deviation is, but it's definitely broad enough to
cause serious distortion on my TS-2000 (which is set up for ham FM
deviations of around 5 KHz). My recollection is that TV audio carrier
deviation is similar to that of commercial FM broadcasts.

It's possible that your IC-706 isn't willing/able to lock onto a
carrier with such a high deviation, perhaps? or perhaps it needs to
be switched manually to a "wide FM" mode to do so in this frequency
range?

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!