[amsat-bb] Re: echo

[Nate Duehr]

On Aug 25, 2006, at 10:08 AM, McGrane wrote:

>
> I should explain my setup here;
>
> FT8800 dual band FM rig for recieve
> 8 element yagi with mast mounted 18 db hamtronics preamp
> 25 feet of 9913 coax

Hasn't the FT-8800 been shown by some folks to have a "barn-door"  
wide receiver?  I can't find the link for any real lab reports on it  
at the moment, and all the manufacturer's put on their brochures  
these days are the same numbers for just about every radio... .2 uV  
for 12 dB SINAD, etc... etc... etc... no real good specifications on  
how they perform with lots of off-frequency noise and or other crud.

Putting a high gain pre-amp in front of it without some bandpass  
filtering is likely just crushing it.  Can you see how it performs  
without the pre-amp and do live comparisons?  You may find the pre- 
amp is actually making things worse.

Amplifying noise and bringing in more out of band signals sometimes  
isn't very useful... (GRIN).

--
Nate Duehr - WY0X
nate@natetech.com