Fw: [Icom] Summary of 60 Meter Performance of IC-765 (long)

[George, W5YR]

Floyd, I reviewed the schematics for the 765 and the TX Tone control has no
effect on the transmit audio introduced via Pin 4 of ACC1. That audio signal
is injected just before a buffer amp that feeds the balanced modulator,
while the TX Tone control affects the mic preamp stage.

I haven't run any checks on the effectiveness of the TX Tone control, but
surely it rolls off the high end to some extent and that might be enough to
buy some insurance on that end of the channel. The problem is that unless
some is also rolled off the low end to maintain balance, the result can be a
bassy boomy sound that is hard to copy and not very pleasant.

Makes me appreciate my PROs with their selectable TX bandwidths!

73/72, George
Amateur Radio W5YR -  the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"
<mailto:w5yr@att.net>





----- Original Message -----
From: "George, W5YR" <w5yr@att.net>
To: <icom@mailman.qth.net>
Sent: Wednesday, June 04, 2003 8:40 PM
Subject: Re: [Icom] Summary of 60 Meter Performance of IC-765 (long)


> Good point, Floyd - no, I did not experiment with that control and I do
not
> recall from the schematics if it affects the ACC1 input. I seriously doubt
> that it does, however.
>
> More work to be done!   <:}
>
> Thanks for pointing this out.
>
> 73/72, George
> Amateur Radio W5YR -  the Yellow Rose of Texas
> Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
> "In the 57th year and it just keeps getting better!"
> <mailto:w5yr@att.net>
>
>
>
>
>
> ----- Original Message -----
> From: "Floyd Sense" <sentek@sprintmail.com>
> To: <icom@mailman.qth.net>
> Sent: Wednesday, June 04, 2003 7:33 PM
> Subject: Re: [Icom] Summary of 60 Meter Performance of IC-765 (long)
>
>
> > George - wonder if you've ever looked at the effect of the 765's "mic
> tone"
> > control on the upper end of the transmitted signal?  I haven't looked,
but
> > suspect that it is not in the circuit when inserting the audio signal
into
> > the ACC1 pin.
> >
> > K8AC
> FAQ: http://www.qsl.net/icom/
>