[ICOM] Re: 7000

[bonddaleena at aol.com]

Update on my perceived R7000 off frequency problem.....

My last test was as follows:

756PRO tuned to 50.125.0 MHz USB
The R7000 received it at 50.123.5 MHz, perfectly

Next, I switched the PRO to LSB
Pushing the 'SSB selector' button on the rear of the R7000 to LSB, 
resulted in the clear LSB signal being received perfectly on 50.123.5 
MHz

I went to Icom's 'Knowledge Base' and of the 3 entries for the R7000, 
one was "My radio is off frequency".
Icon describes which trimmer to adjust, test point, etc.
Must be a common problem...


thanks gang!!!

ron

N4UE

-----Original Message-----
From: Mel Martin <ve2dc at videotron.ca>
To: bonddaleena at aol.com
Sent: Sat, 20 Dec 2008 4:25 pm
Subject: Re: 7000


I think you have mis-understood what was being suggested. They were NOT 
suggesting you were on the wrong sideband... 
 
Let me explain it in a bit more detail... understanding that it's 
probably wrong nonetheless ;-) 
 
Most amateur radios equipment for SSB, by convention, indicates the 
carrier frequency in the frequency readout. If you have an USB signal 
indicating 50.125, the actual signal occupies a 3KHz channel centered 
on 50.1265. On LSB, the actual channel is 3KHz centered on 50.1235. So 
when you switch from USB to LSB the radio simultaneously has to move 
3KHz. Easily done with modern radios, but older radios and maybe some 
modern radios indicate the channel20center frequency, not the carrier 
frequency. Note that on AM or FM, we always indicate the center channel 
frequency. 
 
In any case, it seems the frequency read-out error is offset 1.5KHz in 
the wrong direction so I believe you are probably correct that the 
IC7000 calibration is a little off. 
 
bonddaleena at aol.com wrote: 
> > Thanks to all who replied. Several folks have suggested that I may 
have > been listening on the wrong Side Band. 
> > I did the following last night: 
> > Tuned the 756PRO to 50.125.0 USB 
> > Turned down the RF power AND connected it to my Heath Cantenna 
> > Tuned the R7000 to 50.125.0 USB 
> > Turned the Voice Keyer for the Pro on and listened on the R7000 
> > I could hear my signal OFF FREQUENCY. Tuning the R7000 to 50.123.5, 
my > signal was perfect 
> > Just for grins, I checked the USB/LSB switch on the rear of the 
R7000. > It indeed WAS on USB. Engaging LSB made my signal sound 
horrible and > tuning the receiver did NOT produce a clear signal. 
> > So, the display is indeed 1.5 KHz low.... 
> > ron 
> > N4UE 
> > -----Original Message----- 
> From: Mel Martin <ve2dc at videotron.ca> 
> To: bonddaleena at aol.com 
> Sent: Sat, 20 Dec 2008 7:01 am 
> Subject: 7000 
> > > Are you sure it is not reading the center channel frequency and 
not the > carrier frequency. Just a thought...
 if that were the case it 
would be > easy to check... it would be 1.5KHZ high on LSB > > -- Mel, 
VE2DC > >  
-- Mel, VE2DC