Message-ID: <002501c19762$44106980$596152d5@it>
From: "Giulio Scaroni" <scaroni@phoenix.it>
To: rsgb_lf_group@blacksheep.org
References: <XFMail.020123225327.cla.po@tiscalinet.it>
Subject: LF: Re: Jason is easy and cheap!
Date: Mon, 7 Jan 2002 10:59:47 +0100
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Claudio wrote:


> Just received M0BMU beacon with a minumum station!
>
> This is a good test for the receiving station to be exposed the next
week-end
> in hamfest! I hope for some signal in the week-end for our show.
>
> A tuned loop on my balcony, 100 meters of SAT-TV cable, homemade direct
> conversion RX, an old savaged 100MHz Pentium with 16 Mb ram...
>
> Yes, some errors but a very good Euro/error ratio!
>
> some garbage...DE MBMU JASON92U0BMU JASON92 DE M0BMU M0BMU JASON92 DE
M0BMU
> M0BMU JASON92 M0BMU M0BMU JASON92 M0BMU M0BMU SON92 M0BMU M0BMU JASON92
> QRV2300Z ON 135990 DE M0BMU SK
>
> Now I try again with a more performant computer!
>
> 73 de Claudio

The same here!!!
Very good copy of M0BMU, with my tx antenna, and a IC 738 with Mini Circuit
DBM, the only problem is that i have switched on the OCXO 5 Mhz by
Oscilloquartz too late, so , it has take 1 hour to go in temperature, so
captured only the end of trasmission, but also with Gram 5.1 was perfectly
readable!
Now i'm using my IC 775 that is very good on LF, like the 738 with DBM
converter, but, i'm using not the original P.S.U. of 775 becouse the
original P.S.U. is a switching model, with switch frequency fo about 70 KHZ,
so is impossible to use the 775 in LF for the strong second armonic!!!!!!
About the Jason, i think that is a very original mode, don't need to look
the screen for many time to read the qrss or dfcw, but this last mode are
also very interesting.
About my test 2 days ago, when i was trasmitting, in the middle of
trasmission, with only 20 w with rain wx, 2 of the 3 wire at the top of
antenna that make the capacitive loading has fired and dropped down to the
vertical part of the antenna, so 20 W, rain, and antenna broken, the Jason
has worked well and reports of good reception from I5TGC was sended me, a
test with very poor Tx condition!!!
About the TX for Jason, i have used like exciter the IC 738 at 5.137 Mhz
with PC to mike input, OL 5 Mhz Oscilloquartz, Mini Circuit DBM , and two
transistor for amplifier the low signal from DBM, then the TX is a single
IRF 640 that deliver 100 W out at 17 Vcc.
But  the problem is that switching off on PC the Jason from TX to stand by,
the sound card give a noise signal to the TX that go into autooscillation,
so need to switch off all two togheter at the same time, i think that is
better  a DDS source, good also for dfcw!!

73 to all and saturday from 8.00 to 17.00 i'll tx on beacon mode for the
Milano - Novegro hamfest, at 137.520 in Jason, qrss 3, for this special
event!!

Giulio Scaroni IK2DED.