[Lowfer] MFSK 8 and MFSK16 Comments

[n8tl]

Hi Jay:

I agree with your summary.   MFSK16 is a bit more robust, particularly, if you factor in static and band fade issues.

However, when the signal level fades to less than s/n +2...copy goes to pieces in a hurry for most any mode...possible exception would be WOLF.  My receiver is not GPS sync'd, however, it does have the IC-R75 high stability oscillator function so set and forget copy at this end is pretty much a given if the signal level is reasonable.  Also, the AFC option in MultiPSK gives the same result at this end of the signal pipe.

My receive setup is not fancy.....an IC-R75 powered by independant of mains 13.8 volt DC. Antenna is untuned 140 foot
loop w/ Ae about 1575 sq foot.  I have an AMRAD vlf converter also feeding in the spare antenna input....also DC powered.
The antenna coax is grounded independant of mains ground and isolated by a 1:1 (25 turn) ferrite transformer to further
reduce noise pickup. 

I'm currently working on a AF bandpass filter for the soundcard input from the RX. It will be 10 hertz bandwidth centered on
500 hertz. Next project is a high stability oscillator for the AMRAD converter.

Regards,

Tom N8TL
Findlay, Ohio EN81ha