[RTTY] External DSP devices

[Bill Coleman]

On Jan 29, 2006, at 7:57 PM, K8JWT wrote:

> I am looking into buying a external DSP device for contesting as my  
> Yaesu
> FT-840 is crappy on SSB/RTTY as I can hear stations as far as 2.5KC  
> away
> from me.

While these external devices certainly work, they can only have a  
limited amount of effectiveness. Any signal in the passband will pump  
the AGC of the rig before it gets to the audio stages of the DSP  
filter. If the interfering signal is strong, it can attenuate the  
desired signal enough to make it unreadable.

You'd get more bang for the buck by installing narrow (~500 Hz)  
crystal filters in your rig, or perhaps in upgrading to a rig that  
supports these types of filters.


Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net
Quote: "Not within a thousand years will man ever fly!"
             -- Wilbur Wright, 1901