Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-di01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 83E00380000CA; Fri, 12 Oct 2012 14:27:17 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1TMja0-0006E3-Rd for rs_out_1@blacksheep.org; Fri, 12 Oct 2012 19:03:24 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1TMja0-0006Du-7F for rsgb_lf_group@blacksheep.org; Fri, 12 Oct 2012 19:03:24 +0100 Received: from out1.ip07ir2.opaltelecom.net ([62.24.128.243]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1TMjZy-0004rh-0h for rsgb_lf_group@blacksheep.org; Fri, 12 Oct 2012 19:03:23 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AiAFAExaeFBOk8VF/2dsb2JhbABFqHKEapIIgQmCGwUBAQUIAQEDGi8CLAEBAwUCAQMRBAEBCiUUAQQaBgwKCAYTCgECAgEBh2EDBg0HrCaOOQSKbGYVBoYiA41phjOMdIUNgm2BWwg X-IronPort-AV: E=Sophos;i="4.80,577,1344207600"; d="scan'208,217";a="50321470" Received: from host-78-147-197-69.as13285.net (HELO xphd97xgq27nyf) ([78.147.197.69]) by out1.ip07ir2.opaltelecom.net with SMTP; 12 Oct 2012 19:03:20 +0100 Message-ID: <005001cda8a3$dc6059d0$0501a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <50783F5D.60809@iup.uni-heidelberg.de> Date: Fri, 12 Oct 2012 18:03:19 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 4.4 (++++) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Yes Stefan You go to bed and leave a machine churning out Beacon callsign es Locator. That is not amateur radio but Appliance Operator black box syndrome. You do not need to be a Radio Amateur for such operations just a plug and play Robot I suppose this approach avoids perfecting a Receiver that works, just rely on the Internet for some sort of response. [...] Content analysis details: (4.4 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 4.4 AXB_XMAILER_MIMEOLE_OL_024C2 AXB_XMAILER_MIMEOLE_OL_024C2 X-Scan-Signature: f9bb43a66658129469273581af35b296 Subject: LF: Re: WSPR on the 630m band Content-Type: multipart/alternative; boundary="----=_NextPart_000_004D_01CDA8A3.DC272160" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=HTML_MESSAGE autolearn=no version=2.63 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-aol-global-disposition: G x-aol-sid: 3039ac1da605507861053c20 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ------=_NextPart_000_004D_01CDA8A3.DC272160 Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable Yes Stefan=20 You go to bed and leave a machine churning out Beacon callsign es = Locator. That is not amateur radio but Appliance Operator black box = syndrome.=20 You do not need to be a Radio Amateur for such operations just a plug = and play Robot I suppose this approach avoids perfecting a Receiver that works, just = rely on the Internet for some sort of response. de G3KEV ----- Original Message -----=20 From: Stefan Sch=E4fer=20 To: rsgb_lf_group@blacksheep.org=20 Cc: Vasily Savchenko=20 Sent: Friday, October 12, 2012 4:03 PM Subject: LF: WSPR on the 630m band MF! Last night i built a transmit converter which allows me to transmit = WSPR on 630m now. Yes yes yes yes yes Mal, CW is preferred! But many OMs go to bed quite = early i find. Not so their PCs, they run over night, and so my = transmitter will do this weekend if all goes right. :-) I'm not present = in the shack anyway, so no chance for CW... I'm using normal WSPR, not the slow versions. Right now the first tests are running and i check if the system = becomes to warm. The design of this mixer is quite chaotic but i like it :-) It is a = modular system...: First, a tone of 14700 Hz is generated by the WSPR = program. Is is decoupled from anything by an audio isolating = transformer. This signal is applied to a SA612 mixer. The LO (461 kHz) = in this test setup comes fom my DDS VFO which is used in the first VLF = experiments. The output looks very well as expected on the scope. = Filtering of mixing products is done in my MF meachanical filter which = is use in front of the receiver normally! I've published the nearly = perfect filter curve some weeks ago. Of course the sine wave coming out = from the filter looks very well! This sine wave is applied to an OP AMP = which is switched as a comparator. I've added a small hysteresis (10 = MOhm / 47k) to prevent an oscillating output when there is no input = signal. Works well! The output of the OP AMP is fed to a ICL7667 (FET = driver) which makes a low impedant output. In series with 1 Ohm and 1 uF = this rectanfgular waveform is applied to a small ferrite toroid with a = trifilar winding. So this output is again galvanically decoupled from = the circuit and provides an opposite phase rectangular signal at 475.7 = kHz.=20 Since my PA was/is designed to have a 4f input (1900 kHz -> 475 kHz = out) i had to make a tap behind the divider, so i have to take care to = maintain the 50 % duty cycle in the new circuit. The new external drive = signal from the converter is applied by a simple headphone jack/plug! I = actually found a 3.5mm stereo-jack with dimensions 10mm x 5mm and also = found a few holes to add this on the board. So the PA is now able to run = as before and additionally with this new converter...... The AF signal levels and the LO signal level is critical. Choosing = wrong values will change the 50% duty cycle which will quickly kill the = FETs in this PA design. So i'm using an old modified PC power supply = that will shut down quickly if the current exceeds a certain limit... After writing this email the PA became hand warm so it looks all fine. = I will go down to 50% TX duty cycle now and even receive during the = breaks in WSPR. However the MF filter is now used for the TX so the RX = performance may be slightly lowered... Reports about my transmissions on 475.700 kHz are very welcomed. I'm = also receiving and uploading to the WSPR database... Maybe i will run the test until monday :-) Best 73, Stefan/DK7FC PS: https://dl.dropbox.com/u/19882028/MF/stuff.JPG ------=_NextPart_000_004D_01CDA8A3.DC272160 Content-Type: text/html; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable
Yes Stefan
You go to bed and leave a machine churning out = Beacon=20 callsign es Locator. That is not amateur radio but Appliance Operator = black box=20 syndrome.
You do not need to be a Radio Amateur for such = operations=20 just a plug and play Robot
I suppose this approach avoids perfecting a = Receiver that=20 works, just rely on the Internet for some sort of response.
 
de G3KEV
 
----- Original Message -----
From:=20 Stefan = Sch=E4fer
Sent: Friday, October 12, 2012 = 4:03=20 PM
Subject: LF: WSPR on the 630m = band

MF!

Last night i built a transmit converter = which allows=20 me to transmit WSPR on 630m now.

Yes yes yes yes yes = Mal, CW is=20 preferred! But many OMs go to bed quite early i find. Not so their = PCs, they=20 run over night, and so my transmitter will do this weekend if all goes = right.=20 :-) I'm not present in the shack anyway, so no chance for = CW...

I'm=20 using normal WSPR, not the slow versions.

Right = now the=20 first tests are running and i check if the system becomes to = warm.

The=20 design of this mixer is quite chaotic but i like it :-) It is a = modular=20 system...: First, a tone of 14700 Hz is generated by the WSPR program. = Is is=20 decoupled from anything by an audio isolating transformer. This signal = is=20 applied to a SA612 mixer. The LO (461 kHz) in this test setup comes = fom my DDS=20 VFO which is used in the first VLF experiments. The output looks very = well as=20 expected on the scope. Filtering of mixing products is done in my MF=20 meachanical filter which is use in front of the receiver normally! = I've=20 published the nearly perfect filter curve some weeks ago. Of course = the sine=20 wave coming out from the filter looks very well! This sine wave is = applied to=20 an OP AMP which is switched as a comparator. I've added a small = hysteresis (10=20 MOhm / 47k) to prevent an oscillating output when there is no input = signal.=20 Works well! The output of the OP AMP is fed to a ICL7667 (FET driver) = which=20 makes a low impedant output. In series with 1 Ohm and 1 uF this = rectanfgular=20 waveform is applied to a small ferrite toroid with a trifilar winding. = So this=20 output is again galvanically decoupled from the circuit and provides = an=20 opposite phase rectangular signal at 475.7 kHz.
Since my PA was/is = designed to have a 4f input (1900 kHz -> 475 kHz out) i had to make = a tap=20 behind the divider, so i have to take care to maintain the 50 % duty = cycle in=20 the new circuit. The new external drive signal from the converter is = applied=20 by a simple headphone jack/plug! I actually found a 3.5mm stereo-jack = with=20 dimensions 10mm x 5mm and also found a few holes to add this on the = board. So=20 the PA is now able to run as before and additionally with this new=20 converter......

The AF signal levels and the LO signal level is = critical. Choosing wrong values will change the 50% duty cycle which = will=20 quickly kill the FETs in this PA design. So i'm using an old modified = PC power=20 supply that will shut down quickly if the current exceeds a certain=20 limit...

After writing this email the PA became hand warm so it = looks=20 all fine. I will go down to 50% TX duty cycle now and even receive = during the=20 breaks in WSPR. However the MF filter is now used for the TX so the RX = performance may be slightly lowered...

Reports about my=20 transmissions on 475.700 kHz are very welcomed. I'm also receiving and = uploading to the WSPR database...
Maybe i will run the test until = monday=20 :-)

Best 73, Stefan/DK7FC

PS: https://dl.dropbo= x.com/u/19882028/MF/stuff.JPG
------=_NextPart_000_004D_01CDA8A3.DC272160--