Ron-
You do not need 2 serial ports to control the rig for FSK. The MMTY site
has a dandy
interface that uses 3 pins of the 9 pin serial output; ground, PTT, and
key FSK. It
uses 2 transistors and 2 resistors to connect the radio to the computer. The
RigBlaster gives you a keying output and FSK output, look in the manual.
By using the FSK input of the MP you will shift the if of the receiver
to center the
RTTY signal in the passband. Then you can use all the filters you have
installed, in my
case with a Mark V I have a 250 cycle CW filter which works perfect for
170 Hz shift
of RTTY. When using AFSK, without getting into menus and shifting
offsets, you have to
crank the passband tuning almost full clockwise to get the signal in the
middle of
the passband. Unlike the Mark V the MP allows using narrow filters in
audio modes.
I might add I use the serial port for the RigBlaster, which is connected
to the Packet input,
allowing PSK, SSTV and other audio modes. I made the interface I
mentioned earlier to
connect the parallel port to the RTTY input. I then do not have to mess
with changing mike
connectors, turn off the processor, etc.
You will need a few software add on's to MMTY but it works slick to
operate the Yaesu in a
mode and in a way it was designed for.
Another note, when I used AFSK, "where am I" is an issue if you use
spotting. As the signal
is shifted by whatever audio frequencies you use, the dial does not
match what's on the
spot list. I also noted some slight shifting in output power when
transmitting AFSK, no
doubt due to audio response in the radio not being dead on.
There is a wealth of info to be found on www.aa5au.com/rtty.html. This
site should answer
most of your questions.
See you on the bleedley beep!
ed K0KL
On 3/17/2011 7:05 PM, KU7Y wrote:
> Hi All,
>
> Another question.....
>
> In trying to hook these up it looks like I need to have 2 serial ports to
> control the rig and do FSK. Is that right?
>
> Is there any big reason to not use AFSK?
>
> The laptop I have for this use only has one serial port. It does have a
> printer port if there is a way to use that.
>
> Thanks for the BW.
>
> OK, back in my hole,
>
> Ron, KU7Y
> SOWP 5545M
> Arizona Outlaws Contest Club
> Brenda, AZ (Winter)
> Caldwell, ID (Summer)
> ku7y@qsl.net
> http://www.hatpinsandmore.com
>
> _______________________________________________
> RTTY mailing list
> RTTY@contesting.com
> http://lists.contesting.com/mailman/listinfo/rtty
>
>
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