DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws;
  s=s1024; d=btinternet.com;
  h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding;
  b=QO9wOepIZvUcg0Gf38nvfMs3FS0BlOIBEJGzMvXjwuqW1FZQWZHxjdRieR/isyOA+21swJD7VpRFXobBToeJ1D4qxgnaR2554ZCTIaqnmW+roe6U75UFTuxmTMa5MAqMp3RLgVPim3ACyTeAPd2SkeimxDevRdUO/muPf5xmWKc=;
Message-ID: <20250.29213.qm@web86503.mail.ird.yahoo.com>
Date: Wed, 9 Dec 2009 22:32:34 +0000 (GMT)
From: ALAN MELIA <alan.melia@btinternet.com>
To: rsgb_lf_group@blacksheep.org
In-Reply-To: <510B0611943F48E1975A8F833B63FBD5@AGB>
MIME-Version: 1.0
DomainKey-Status: good (testing) 
Subject: Re: LF: 500kHz simple 5W TX/RX transverter >>DATA MODES<<
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org


Sounds good Roger and Graham... what it the stability like the problem wit=
h transverters/upconverters normally is that while ok for some modes they=
 are  often not stable enough for the very weak signal modes. These are mo=
des where you need to know the frequency of a station very accurately beca=
use you will not hear it, or it will only pop above the noise for short pe=
riods.

Alan G3NYK


--- On Wed, 9/12/09, Graham <g8fzk@g8fzk.fsnet.co.uk> wrote:

> From: Graham <g8fzk@g8fzk.fsnet.co.uk>
> Subject: LF: 500kHz simple 5W TX/RX transverter >>DATA MODES<<
> To: rsgb_lf_group@blacksheep.org
> Date: Wednesday, 9 December, 2009, 22:13
>=20
>=20
> =20
> =20
>=20
>=20
> =20
> All=20
> =20
> This  latest=20
> addition to  the =20
> HF / MF  tx convertor  opens the  door
> to  data =20
> communications  on 500 ... ranging  from
> 'all'  the K1JT systems=20
> through to  the  single carrier=20
> multi  tone
> systems  of  =20
> MFSK  ,  DOMINO and THOR  .. even
> the  almost=20
> forgotten  Amtor-arq  and Packtor modes , anyone
> still  have=20
> there pk232 =20
> =20
> listed  are=20
> data  modes that  may be  used with
> non-linear systems :-=20
>=20
> =20
> http://groups.google.com/group/uk500khz/web/meat-grinder-comms
> =20
> G..=20
>=20
>=20
>=20
>=20
> From: Roger
> Lapthorn=20
> Sent: Tuesday, December 08, 2009 12:20 AM
> To: rsgb_lf_group@blacksheep.org
>=20
>=20
> Subject: LF: 500kHz simple 5W TX/RX
> transverter
>=20
> Dear All,
>=20
> My WSPR tx up-converter has now been modified to=20
> a full TX/RX tranverter suitable for WSPR, QRSS and
> CW  in a=20
> very simple way, making use of the FT817 split
> facility which allows you=20
> to RX on 500kHz and TX on 28MHz. By adding a series LC
> between the TX PA and the=20
> FT817 input/output RF connection (with back-to-back diodes
> at the L and C=20
> junction, this allows "pass through" from the
> 500kHz ATU to the FT817 on RX=20
> (tuned to 500kHz). On TX, the diodes conduct and the C part
> is in parallel with=20
> the first cap in the TX low pass filter. This scheme is now
> working really well=20
> with good RX sensitivity and no change in TX power out.
>=20
> Schematic of the=20
> transverter is on my blog at http://g3xbm-qrp.blogspot.com/
> . My=20
> attempt to add it as an attachment to an email here earlier
> failed.
>=20
> This more or less concludes my 500kHz experimenting, apart
> from=20
> getting a few more CW QSOs in the log. It's been great
> fun all the way with lots=20
> of support from folks here. I was going to try 136kHz, but
> think I will now give=20
> this a miss for now.
>=20
> 73s
> Roger G3XBM
> --=20
>=20
> -------------------------------------------------------------
> http://g3xbm-qrp.blogspot.com/
> http://www.g3xbm.co.uk
> G3XBM  =20
>  GQRP 1678      ISWL G11088
>=20
>=20
>=20
> =20
>=20