[UK-CONTEST] interface problem

[Andy Swiffin]

>>> On 22/01/2011 at 10:01, in message <4D3AAB07.2090700 at btinternet.com>, David
G3YYD <g3yyd at btinternet.com> wrote:
> Roger
> 
> Do you really need to use FSK?

Absolutely you do!!

> It is better to use AFSK as this gives 
> more operational flexibility and avoids the FSK problem.

Why more operational flexibility?    On my TS2000 I have some really nice filtering own to 250hz which I can use with FSK, whereas the SSB filtering is not that good up there (but fine for ssb)

Why on earth use FSK with all its intermod and distortion problems when you can use a pair of pure carriers generated for the job.

> However I know 
> some rigs do not allow the narrow filters to be used with AFSK/SSB. 
> (Please identify the rig to users if this is the case and they will know 
> not to buy such a limited rig)

Not a limited rig,  just designed for people to use the correct method of generating each mode.    Does your rig do 1.8 MHz to 432 MHz tx?  Mine does,  really handy for flicking between 50 and 144 during auroras and sporadic E.

> 
> FSK/N1MM/MMTTY needs to use a dedicated serial port for the FSK shift. 
> It cannot share the port with anything else. SK. 

Not true.  

My g4zlp interface uses one USB to generate the port and the generated virtual port is shared between FSK CW  PTT.    EXTFSK expects you to be using the same port for ptt and fsk.

I've already replied to Roger directly as it didn't seem worthwhile to send it here.   But I'll precis:  the pro+ works great using a single usb to generate all  the usual stuff, plus direct FSK.   You need the EXTFSK dll which comes with the mmtty distribution and when you pick the appropriate setting in mmtty this is automatically fired up.

Sorry,  but I think saying to people to use AFSK when they have FSK easily available is really bad advice!!    I expect AFSK was responsible for some of the horrendous signals I heard around the bands  over last weekends contest.    You don't need to set it up badly, but many do!


Regards
Andy
gm8oeg




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