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View Full Version : what about the mode you're in?



kd5log
07-24-2021, 06:15 AM
my boat anchor has different modes; LSB, USB, AM, FM, FSK, and CW mode. i must select a mode before i transmit. i push a button to get into each mode. my 767gx does not allow code to be sent (with a straight key) on any mode other than CW, unless i'm using a computer interface. but, when just listening in to other people transmitting, i've noticed that i can receive transmissions from some people on all modes, meaning, when these people transmit, i can receive them on all modes, some modes are clearer than others but i can hear them on all modes. how is this possible?:smoker:

N8YX
07-27-2021, 09:28 AM
Filters.

A station being received in CW "mode" (actually, USB with a narrower filter and a different BFO offset) will sound different than the same station being received in USB - even though the signals fall on the same side of zero-beat.

Ditto receiving a station on FSK instead of LSB.

I don't have a link handy, but if you do a search for "SSB receiver design theory" you should find a good starting point for the basics.

kd5log
07-29-2021, 07:12 AM
word up, dawg, thank ya'