Front end overload.

It's like trying to see a candle next to a spotlight shining in your face.

Radioman wrote in message ...
Front end overload.

It's like trying to see a candle next to a spotlight shining in your face.

Even though they are different freqs? I'm transmitting on 146.400,
but listening on 147.00 (-600k offset). Is there anything I could do
to treat the symptom aside from keeping the antennas of the two units
far apart from each other? I wish I had a spectrum analyzer. I'd
love to see definitively what is happening to the spectrum when I
transmit. Maybe there is a way I can turn my old oscilloscope into a
spectrum analyzer. hmmmmmmm...

KC2MAC

On 2 Dec 2003 09:32:01 -0800, (KC2MAC) wrote:

Radioman wrote in message ...
Front end overload.

It's like trying to see a candle next to a spotlight shining in your face.

Even though they are different freqs? I'm transmitting on 146.400,
but listening on 147.00 (-600k offset).

You may think it's a lot, but 600 kHz to an FM radio can be quite
close.

Is there anything I could do to treat the symptom aside from keeping
the antennas of the two units far apart from each other?

See my other response regarding antenna polarization and duplexers.
You could actually build a simple notch filter out of a piece of coax
and a T fitting. It's not going to be very deep, and it will be wider
(in terms of bandwidth) than a duplexer, but every dB helps in this
case.

I wish I had a spectrum analyzer. I'd love to see definitively what is
happening to the spectrum when I transmit.

Look at any transmitter product review in QST, especially HF gear.
Basically what you will see is a very high spike at the transmit
frequency, with progressively diminishing sidebands for several
hundred Hz either side of the carrier frequency. There will also be
some highly attenuated spikes at periodic intervals above and below
the carrier frequency.

Maybe there is a way I can turn my old oscilloscope into a spectrum
analyzer. hmmmmmmm...

Probably not.

LRod

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

http://www.woodbutcher.net

Hey - Merry x-mass Rod...

from the cold in Naperville....
Wes

"LRod" wrote in message
...
On 2 Dec 2003 09:32:01 -0800, (KC2MAC) wrote:

Radioman wrote in message
...
Front end overload.

It's like trying to see a candle next to a spotlight shining in your
face.

Even though they are different freqs? I'm transmitting on 146.400,
but listening on 147.00 (-600k offset).

You may think it's a lot, but 600 kHz to an FM radio can be quite
close.

Is there anything I could do to treat the symptom aside from keeping
the antennas of the two units far apart from each other?

See my other response regarding antenna polarization and duplexers.
You could actually build a simple notch filter out of a piece of coax
and a T fitting. It's not going to be very deep, and it will be wider
(in terms of bandwidth) than a duplexer, but every dB helps in this
case.

I wish I had a spectrum analyzer. I'd love to see definitively what is
happening to the spectrum when I transmit.

Look at any transmitter product review in QST, especially HF gear.
Basically what you will see is a very high spike at the transmit
frequency, with progressively diminishing sidebands for several
hundred Hz either side of the carrier frequency. There will also be
some highly attenuated spikes at periodic intervals above and below
the carrier frequency.

Maybe there is a way I can turn my old oscilloscope into a spectrum
analyzer. hmmmmmmm...

Probably not.

LRod

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

http://www.woodbutcher.net

On Thu, 25 Dec 2003 16:50:59 GMT, "TheTenor"
wrote:

Hey - Merry x-mass Rod...

from the cold in Naperville....
Wes

Holy ****, aren't I safe anywhere?

How're things?

LRod

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

http://www.woodbutcher.net

Well, using the moniker "LRod" is kinda like flashin' your headlights at me
as we pass in the dark g.

Nah - you're safe enough...

Hey I installed an FT817 in my Honda Accord and one of these days I'm gonna
buy a mobile antenna so I can play hf and 6m on it. So far I'm only on 2m
and 70cm. My son, Tom, actually dug out his old handi-talkie and we had a
short qso on what used to be AFAR uhf. Trying like hell to play a bit more.
This running my own business has kept my plenty busy...

Anyway, enough of this conversation on a public forum. Just had to at least
say "hi"... Ever get back up this way? If ya do, look me up. Actually I may
be in Miami Lakes this March. My big client reps a hotel/golf resort there
and his winter meeting is at the hotel. Don't remember where you are but
thing you are further north...

Wes


"LRod" wrote in message
...
On Thu, 25 Dec 2003 16:50:59 GMT, "TheTenor"
wrote:

Hey - Merry x-mass Rod...

from the cold in Naperville....
Wes

Holy ****, aren't I safe anywhere?

How're things?

LRod

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

http://www.woodbutcher.net