Icom IC-745 question (how does CW mode work?)
 

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio gain,
there is some slight noise in the background. If I turn the squelch (close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio gain,
there is some slight noise in the background. If I turn the squelch (close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio gain,
there is some slight noise in the background. If I turn the squelch (close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio gain,
there is some slight noise in the background. If I turn the squelch (close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
.. .
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
.. .
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
.. .
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
. ..
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
. ..
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
. ..
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

Bob Miller wrote:
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Unless the filter was removed incorrectly by a previous owner. For example my
TS50 requires that a jumper board be put in place of the CW filter board if it
is removed. If the IC745 has such a jumper board, and it was not replaced after
a filter removal, then the CW mode might very well appear dead. Just a guess of
course.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in. At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Or maybe it really is operator error as you suggest. Lets hope so... ;)

Bob Miller wrote:
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Unless the filter was removed incorrectly by a previous owner. For example my
TS50 requires that a jumper board be put in place of the CW filter board if it
is removed. If the IC745 has such a jumper board, and it was not replaced after
a filter removal, then the CW mode might very well appear dead. Just a guess of
course.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in. At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Or maybe it really is operator error as you suggest. Lets hope so... ;)

Bob Miller wrote:
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Unless the filter was removed incorrectly by a previous owner. For example my
TS50 requires that a jumper board be put in place of the CW filter board if it
is removed. If the IC745 has such a jumper board, and it was not replaced after
a filter removal, then the CW mode might very well appear dead. Just a guess of
course.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in. At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Or maybe it really is operator error as you suggest. Lets hope so... ;)

On Wed, 24 Nov 2004 03:30:18 GMT, Bob Miller
wrote:

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

Make sure PBT and Filter are not switched. I remember some jumpers
that needed changing and that information was in the service manual,
might have been for the IC-740 though.

For PBT to work the IC-745 required both the 9 MHz and 455 kHz filters
be installed.

Seem to remember some stuff we did to get it to work with only one
filter but has been a long time since I looked into the IC-745 and CW
filter installation..
Worked at Icom America for 11 years supporting all products, left 3.5
years ago.

Gary K8IZ

On Wed, 24 Nov 2004 03:30:18 GMT, Bob Miller
wrote:

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

Make sure PBT and Filter are not switched. I remember some jumpers
that needed changing and that information was in the service manual,
might have been for the IC-740 though.

For PBT to work the IC-745 required both the 9 MHz and 455 kHz filters
be installed.

Seem to remember some stuff we did to get it to work with only one
filter but has been a long time since I looked into the IC-745 and CW
filter installation..
Worked at Icom America for 11 years supporting all products, left 3.5
years ago.

Gary K8IZ

On Wed, 24 Nov 2004 03:30:18 GMT, Bob Miller
wrote:

On Tue, 23 Nov 2004 04:04:45 GMT, AaronJ wrote:

"Frank Krozel" wrote:

I agree the ex-owner probably ripped out the filter.
Frank KG9H
"Dick" LeadWinger wrote in message
...
It could be the filters. Unless an FL-52 or FL-53 455 khz filter is
installed, the radio doesn't work when switched to narrow. Take a
look at page 7-1 in the manual. It shows the various combinations of
filters, and which works when.

Dick - W6CCD

On Mon, 22 Nov 2004 12:13:38 -0800, "Joel Kolstad"
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's
supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent. Actually, if I turn up the audio
gain,
there is some slight noise in the background. If I turn the squelch
(close
to) all the way up, the green 'receive' LED will go out and there's no
detectable noise coming from the speaker.

Any idea what I might be doing wrong here? I was expected that there'd
still be some hissing (background noise) coming from the radio even in CW
mode?

Thanks,
---Joel Kolstad

I agree also. You're probably missing the CW filter. However check your manual.
Every rig I've had with an optional CW filter had a way to route the CW mode
through the SSB filter if that filter was not installed, either by the menu or a
jumper.

Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

At least, that's the way my Icom 735 works. The 745 shouldn't be any
different.

Bob
k5qwg

Make sure PBT and Filter are not switched. I remember some jumpers
that needed changing and that information was in the service manual,
might have been for the IC-740 though.

For PBT to work the IC-745 required both the 9 MHz and 455 kHz filters
be installed.

Seem to remember some stuff we did to get it to work with only one
filter but has been a long time since I looked into the IC-745 and CW
filter installation..
Worked at Icom America for 11 years supporting all products, left 3.5
years ago.

Gary K8IZ

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

Be sure the NARROW filter selection is not depressed. I have a 745
also. Great rig!

Steve


On 26 Nov 2004 18:14:40 GMT, unicate (Fred McKenzie)
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

Be sure the NARROW filter selection is not depressed. I have a 745
also. Great rig!

Steve


On 26 Nov 2004 18:14:40 GMT, unicate (Fred McKenzie)
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

Be sure the NARROW filter selection is not depressed. I have a 745
also. Great rig!

Steve


On 26 Nov 2004 18:14:40 GMT, unicate (Fred McKenzie)
wrote:

I've recently acquired an Icom IC-745 and I'm unclear on how it's supposed
to work in CW mode. It does receive in SSB and AM, so in general the
receiver appears to work. When I press the 'mode' button to get it to CW
mode, however, it's just... silent

Joel-

As others have already mentioned, the radio might have had the CW filter
removed without replacing a jumper that was removed when the filter was first
installed.

Someone else may have mentioned the possibility of a defective diode in the
filter-selection circuit.

It is also possible that a crystal is bad in the circuit where USB/LSB/CW are
selected. Newer radios use signals derived from the Phase-Locked Loop
oscillator, but older ones had separate crystals for each mode. I don't know
where the IC-745 falls. If you have another radio to tune to the frequencies
of these crystals, you should be able to tell if one is not working. All three
should be within about 3 KHz of each other.

73, Fred, K4DII

"Bob Miller" wrote in message
...
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel

"Bob Miller" wrote in message
...
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel

"Bob Miller" wrote in message
...
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel

On Sat, 27 Nov 2004 09:19:59 -0800, "Joel Kolstad"
wrote:

"Bob Miller" wrote in message
.. .
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel


There's something you might try to narrow the CW bandwidth on your
745:

On my Icom 735, when in the CW mode, and while using the the 2.3 khz
SSB filter to receive CW, the passband tuning knob operates as a
variable bandwidth filter! If I twist it all the way to the right, the
bandwidth is 2.3 khz. And if I twist it all the way to the left, the
bandwidth is narrowed to as little as 800 hz.

I don't know if the 745 works the same way, but you might give it a
try on a crowded CW band and see if there's a narrowing effect.

Bob
k5qwg

On Sat, 27 Nov 2004 09:19:59 -0800, "Joel Kolstad"
wrote:

"Bob Miller" wrote in message
.. .
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel


There's something you might try to narrow the CW bandwidth on your
745:

On my Icom 735, when in the CW mode, and while using the the 2.3 khz
SSB filter to receive CW, the passband tuning knob operates as a
variable bandwidth filter! If I twist it all the way to the right, the
bandwidth is 2.3 khz. And if I twist it all the way to the left, the
bandwidth is narrowed to as little as 800 hz.

I don't know if the 745 works the same way, but you might give it a
try on a crowded CW band and see if there's a narrowing effect.

Bob
k5qwg

On Sat, 27 Nov 2004 09:19:59 -0800, "Joel Kolstad"
wrote:

"Bob Miller" wrote in message
.. .
Even if the CW filter is missing, he should be receiving CW through
the standard SSB filter.

Just switch to the "CW" mode, and make sure "CW narrow" isn't switched
in.

Thanks Bob, that works! So the problem was that the narrow filter is
missing. :-( Oh well; not that big of a deal.

Thanks to everyone for suggestions.

---Joel


There's something you might try to narrow the CW bandwidth on your
745:

On my Icom 735, when in the CW mode, and while using the the 2.3 khz
SSB filter to receive CW, the passband tuning knob operates as a
variable bandwidth filter! If I twist it all the way to the right, the
bandwidth is 2.3 khz. And if I twist it all the way to the left, the
bandwidth is narrowed to as little as 800 hz.

I don't know if the 745 works the same way, but you might give it a
try on a crowded CW band and see if there's a narrowing effect.

Bob
k5qwg