[1000mp] AW: Different frequency response in USB and LSB

[Uwe Fleischer]

Pete,

as far as I remember (can't have a look into the manual at this moment), ALL
frequencies are adjustable by software in the menu. So probably try a
factory reset first, to see, if something was disadjusted accidentally or
whether the problem still exists after the reset.

73 from Germany
Uwe, DL8UF


-----Ursprüngliche Nachricht-----
Von: 1000mp-bounces at mailman.qth.net [mailto:1000mp-bounces at mailman.qth.net]
Im Auftrag von Pete Smith
Gesendet: Dienstag, 23. Oktober 2007 20:39
An: All about Yaesu 1000mp
Betreff: Different frequency response in USB and LSB

I just focused on something that I think has been happening with my Mk 5 
since it was a pup.  Listening with the stock 2.4 KHz filter, and no 
antenna on the radio, the background hiss/noise is a noticeably different 
pitch on LSB than on USB.  That says to me that the suppressed carrier 
frequency is offset from the filter passband by a different amount in the 
two modes.  This observation is supported by viewing a waterfall display in 
mmtty; I can see that one sideband has far more rolloff than the other at 
higher frequencies, within the filter passband.

The radio now has the Inrad roofing filter in place; as I say, I *think* 
the pitch difference was apparent before I installed it, but one person has 
suggested that the roofing filter's center frequency and/or passband shape 
may be responsible.  I suppose I can temporarily remove it and see, or is 
there an easier way?


73, Pete N4ZR

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