Return-Path: X-Spam-DCC: paranoid 1356; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, NO_REAL_NAME autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id t2J05U48018559 for ; Thu, 19 Mar 2015 01:05:30 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1YYNug-0003lY-AN for rs_out_1@blacksheep.org; Thu, 19 Mar 2015 00:02:14 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1YYNug-0003lP-2J for rsgb_lf_group@blacksheep.org; Thu, 19 Mar 2015 00:02:14 +0000 Received: from nina.ucs.mun.ca ([134.153.232.76]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.85) (envelope-from ) id 1YYNud-000801-7p for rsgb_lf_group@blacksheep.org; Thu, 19 Mar 2015 00:02:12 +0000 Received: from plato.ucs.mun.ca (plato.ucs.mun.ca [134.153.232.153]) by nina.ucs.mun.ca (8.13.1/8.13.1) with ESMTP id t2J026iE032607 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 18 Mar 2015 21:32:07 -0230 Date: Wed, 18 Mar 2015 21:32:06 -0230 (NDT) From: jcraig@mun.ca X-X-Sender: jcraig@plato.ucs.mun.ca To: rsgb_lf_group@blacksheep.org In-Reply-To: <5509E3D5.90900@gmail.com> Message-ID: References: <4698D0522AFD45F896A41F2D16A2D831@AGB> <19EEF7A6DD30462FA6ACC0F015DC9F52@AGB> <5509E3D5.90900@gmail.com> MIME-Version: 1.0 X-Scan-Signature: 1c38f63d01970a2bf149f660c9cb2a37 Subject: Re: LF: TXing WSPR on 630m on a Raspberry Pi, Stefan in QRPPPP... Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 2711 Hi Stefan, That looks very nice. Is there a script for generating RF with a pi? A 500Hz tone is easy but for higher freqs it seems a DDS is needed. 73 Joe VO1NA On Wed, 18 Mar 2015, DK7FC wrote: > Hi MF, > > Today i've got i 3rd Raspberry Pi. I quickly installed the WSPR softaware and > since a few minutes i am transmitting WSPR-2 on 630m, my usual frequency > 475.685 kHz. > > I'm directly using the GPIO output pin, without an amp stage behind! The > rectangular 3.3V output voltage is passing a cap and an isolation transformer > (FT50-77) as well as a simple pi-filter, because it is a Raspberry pi! ;-) > > See: > https://dl.dropboxusercontent.com/u/19882028/MF/Raspberry%20Pi%20B%2B%20WSPR%20TX.jpg > > I measured an output power of about 10 mW at 50 Ohm. It is now connected to > my MF antenna and transmits in a 100% duty cycle. I still have to learn how > to reduce it but this will not take long. > > With 10 mW TX power i managed decodes by 3 stations now. > > 3 spots: > > Timestamp Call MHz SNR Drift Grid Pwr Reporter > RGrid km az > 2015-03-18 20:32 DK7FC 0.475684 -21 0 JN49ik > 0.01 DH5RAE JN68qv 345 98 > 2015-03-18 20:12 DK7FC 0.475685 -24 0 JN49ik > 0.01 F1AFJ JN06ht 667 247 > 2015-03-18 20:06 DK7FC 0.475683 -27 0 JN49ik > 0.01 DL1DBC JO41bi 217 349 > > > > Does someone have good ears to get a decode from me? :-) It is a challenge! > :-) > > 73, Stefan/DK7FC > > PS: The signal is so weak that my RX antenna frontend is not overloaded, so > at that power level i can transmit and receive to the same time :-) > PPS: A small amp stage will follow soon, i intend to use an BS170 running at > 5 V. >