[RTTY] USB to Serial FSK experiment/observations

[Richard W. Solomon]

I don't see any USB to Serial Link ??
Do you mean the USB Smart I/O Link ?

73, Dick, W1KSZ

-----Original Message-----
From: rtty-bounces at contesting.com [mailto:rtty-bounces at contesting.com]On
Behalf Of WB2RHM - Ben Antanaitis
Sent: Saturday, June 04, 2005 11:45 AM
To: rtty at contesting.com
Subject: [RTTY] USB to Serial FSK experiment/observations


All,

I am testing MMTTY's EXTFSK.dll capability to send FSK via a USB
connection, for my own station use.

I have several USB to Serial adapter cables that are based on the Prolific
chipset. These are really very cheap to buy from outlets like
TigerDirect.com (~$9 to $15 depending on the rebates). Several
manufacturers have Prolific based USB to Serial cables for sale there.

Prolific released a new set of drivers in 2004. They can be downloaded from
the
Prolific web site http://tech.prolific.com.tw/visitor/v_fileBrw.asp and then
select the USB to Serial link to find the latest drivers for your system.
These are a higher/newer level than those at any of the cable makers
'download' areas that I've looked at. Windows, and the Prolific based USB
to Serial cables, will accept generic Prolific update/replacement drivers.

I downloaded them, uninstalled the original ones that came with the cables,
and installed the new ones on my WinME based system using the 'installer'
program that comes inside the Prolific update package.

Using MMTTY alone with EXTFSK.dll. I found that I could now send FSK to my
Orion after setting the Windows ME Start>Settings>System>Control
Panel>Device Manager>Com Port>Properties settings to "5" Bits, 1.5 Stop
Bits, No Flow Control, for the USB FSK COM port. The trick seemed to be to
set the com port to what we need for RTTY. I used the EXTFSK USB option of
MMTTY and it seemed to work.

Using Windows 'sound recorder', I recorded my radio's speaker 'output' via
the Orion's 'monitor mode' and then I played it back into MMTTY which
happily decoded everything correctly from the .wav file.

N1MM also seemed to work fine.

Unfortunately, Logger32 seems to do some kind of 'port polling' that chops
up the FSK signal into many 'slices' that destroys the FSK 'keying' signal.

At ~$9 to $15/cable depending on the rebates, this is much cheaper than
some of the latest USB keyer packaged solutions.

I didn't know if I should post my preliminary results on the RTTY contest
reflector yet, especially if I'm the only one who sees these results ;-(
But Don suggested this may help others and spur some more tests.

73, good luck,
Ben Antanaitis
WB2RHM
_______________________________________________
RTTY mailing list
RTTY at contesting.com
http://lists.contesting.com/mailman/listinfo/rtty