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Ok Dennis,
Thanks for the info ... Looking at the distance,
you may be in the 'dead zone' which is a bit of a pain .. I must of seen your
signals on cw later that night , but missed the rtty qso, I don't know
if Gary did any better, annoying thing is, looking at Birmingham, the
signal looked quite strong ! all my tx kit is in a big box at the moment,
but I can receive on 500, with the marine set and the ft897, which
actually works quite well ...
Fine on the rtty / fsk set up , mmty is I
think the only 'free' prog that has that facility ?, a tnc like the pk232
will also key directly, with a few more modes, But, I wonder, have you
considered making one of the tx down convertors, you would only need the tx side
of this > http://www.radiocom.net/txvr.jpg <
could drive in place of the vfo, and use a hf ssb tx to generate via the
sound card, there are a few quite 'hard' stepped tone systems in 'fldigi' ,
which will go via a non linear amp , best system I think,
to date, was the olivia 8 tone 250 bw , that printed very well into
the noise, but needs a linear system, at the time I didn't try the narrow mfsk
... may give similar results ?
Hopefully I will be back on the air by xmas, that's
if the ma1723 has not decided to fall over through lack of use .. if it
dose ill be making a copy of Gary's 'new' rx/tx converter and feeding it from
the ft897 !
Gd luck !
Graham.
Sent: Thursday, October 23, 2008 11:59 AM
Subject: Re: LF: Re: RTTY QSO 500 KHz
Hi Graham
Regarding my RTTY, am using MTTY software with PTT
and FSK signals taken via the computer COM port to TX via two 2N2222
transistors operating as emitter followers. The output of
the FSK stage goes via 5k to a 1k pot with a forward biased silicon
diode across it, to stabilise the voltage at 0.6V. The slider selects
the amount of voltage fed via a 68k resistor to a BA102 varactor in series with
a 25pF trimmer, which is across the tuned circuit of the VFO. The
slider sets the amount of shift from 23Hz to 170Hz, though I would not like to
rely on the 23Hz setting too much, owing to slight drift. This
arrangement normally works well, but I had problems with Chris due to a
modification I made to the VFO for another purpose. I am thinking of
replacing the 2N2222s with opto-isolators, in an attempt to reduce noise on
receive. I also plan to try a loop antenna at the end of the
garden for the same purpose.
73 Dennis M0JXM.
----- Original Message -----
Sent: Wednesday, October 22, 2008 10:03
PM
Subject: Re: LF: Re: RTTY QSO 500
KHz
Dennis,
Interesting on the rtty contact, what method are
you using for 'tx' ?
What is your locator square ? you may be in the
'dead zone' in terns of distance , Gary and myself are roughly the same
distance north , but after 70 miles or so ,there is a 'dead zone' till about
200 , I don't know, may be a band 100 miles wide after that, that's a problem
with the band and as you can see at 600 miles, signals show up quite
well at Shetland, while not showing at Glasgow
I posted this 18/10 , : was that you
on cw ?
Seeing a very low signal on 502.350 no
audio .. looks like a cw cq call ? 60 second tx with 'gap'
35 ft top load .. no atu ... ft897-d atten
'on'
G
G0NBD
IO83LK
Sent: Wednesday, October 22, 2008 5:54 PM
Subject: LF: Re: RTTY QSO 500 KHz
Hi Gary
You may have heared me using RTTY on the 18th as
I had a QSO with Chris G3XIZ earlier which went wrong, and was testing my TX
later during your QSO with him. My main problem is that I appear
to be getting our reasonably well, but not so good on receive so didn't hear
you.
Sorry about that. I am working on the
receive problem which is probably due to high QRN at my location.
73 Dennis M0JXM
----- Original Message -----
Sent: Saturday, October 18, 2008 8:28
PM
Subject: LF: RTTY QSO 500 KHz
Hi
LF,
Just had a
good RTTY QSO with Chris G3XIZ.
Is there any
other station can use RTTY, 45 Baud, 85 Hz shift
?
Please look
for my CQ calls on 503.600 KHz
73,
Gary - G4WGT -
IO83QP.
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