Return-Path: X-Spam-DCC: paranoid 1170; 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=-2.2 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,HTML_MESSAGE 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 t2RAZVnn026330 for ; Fri, 27 Mar 2015 11:35:31 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1YbRYh-0007WX-5W for rs_out_1@blacksheep.org; Fri, 27 Mar 2015 10:32:11 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1YbRYg-0007WM-QB for rsgb_lf_group@blacksheep.org; Fri, 27 Mar 2015 10:32:10 +0000 Received: from smtpcmd01217.aruba.it ([62.149.158.217]) by relay1.thorcom.net with esmtp (Exim 4.85) (envelope-from ) id 1YbRYe-0003vt-CY for rsgb_lf_group@blacksheep.org; Fri, 27 Mar 2015 10:32:09 +0000 Received: from PC-MAURO.stmb.it ([82.56.134.177]) by smtpcmd01.ad.aruba.it with bizsmtp id 8aY51q0083pojBE01aY5F7; Fri, 27 Mar 2015 11:32:06 +0100 X-Mailer: QUALCOMM Windows Eudora Version 7.1.0.9 Date: Fri, 27 Mar 2015 11:32:00 +0100 To: rsgb_lf_group@blacksheep.org, rsgb_lf_group@blacksheep.org From: IK1WVQ Mauro In-Reply-To: <55148587.3090101@gmail.com> References: <4698D0522AFD45F896A41F2D16A2D831@AGB> <19EEF7A6DD30462FA6ACC0F015DC9F52@AGB> <5509E3D5.90900@gmail.com> <55102D0C.8040405@gmail.com> <55148587.3090101@gmail.com> Mime-Version: 1.0 X-Scan-Signature: 3dad7246509e3b317974c9d84e795ac1 Message-Id: Subject: Re: LF: TXing WSPR on 630m on a Raspberry Pi, Stefan in QRP... Content-Type: multipart/alternative; boundary="=====================_17405047==.ALT" 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: 2790 --=====================_17405047==.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed Hi Stefan, years ago I tried a "push_pull" (or, better, "bridge") configuration with a mosfet driver (I do not remember the code) with one section inverting, and the other not.. the power output was over 1W in 10MHz, with 12V supply .. I placed a toroid transformer with the primary winding connected to the two outputs (via a 100nF to avoid short circuit if raspy stop to oscillate) ... .. little PA grow .. HI! 73 de Mauro IK1WVQ At 23:17 26/03/2015, DK7FC wrote: >Hi MF, > >I'm now running the 7667 at 13.8V supply voltage. The MOSFET driver >is easily keyed by the Raspi, directly with its rectangular output. >I measured 0.5 W TX power at 50 Ohm. This is what i'm running tonite on 630m. >Not a real PA, just the Raspi and this IC in a DIL-8 case. Fascinating!... > >73, Stefan > > >Am 23.03.2015 16:11, schrieb DK7FC: >>Hi MF, >> >>I've added a simple ICL7667CPA MOSFET-driver to the GPIO of the >>Raspberry. It's power supply is 5V coming from the GPIO itselfe. >>This leads to a 5V rectangular signal with lower output impedance. >>I've coupled the output matching circuit so that the output power >>is now 50 mW / 17 dBm, i.e. 7 dB more power then in my previous test. >>Iamge: >>https://dl.dropboxusercontent.com/u/19882028/MF/17dBm%20RPI%20WSPR.jpg >> >>The beacon is running now on 475.685 kHz. >> >>73, Stefan/DK7FC >> >> >>Am 18.03.2015 21:45, schrieb DK7FC: >>>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. --=====================_17405047==.ALT Content-Type: text/html; charset="us-ascii" Hi Stefan,
years ago I tried a "push_pull" (or, better, "bridge") configuration with a mosfet driver (I do not remember the code) with one section inverting, and the other not.. the power output was over 1W in 10MHz, with 12V supply ..
I placed a toroid transformer with the primary winding  connected to the two outputs (via a 100nF to avoid short circuit if raspy stop to oscillate) ...

.. little PA grow .. HI!

73 de Mauro IK1WVQ



At 23:17 26/03/2015, DK7FC wrote:
Hi MF,

I'm now running the 7667 at 13.8V supply voltage. The MOSFET driver is easily keyed by the Raspi, directly with its rectangular output. I measured 0.5 W TX power at 50 Ohm. This is what i'm running tonite on 630m.
Not a real PA, just the Raspi and this IC in a DIL-8 case. Fascinating!...

73, Stefan


Am 23.03.2015 16:11, schrieb DK7FC:
Hi MF,

I've added a simple ICL7667CPA MOSFET-driver to the GPIO of the Raspberry. It's power supply is 5V coming from the GPIO itselfe. This leads to a 5V rectangular signal with lower output impedance. I've coupled the output matching circuit so that the output power is now 50 mW / 17 dBm, i.e. 7 dB more power then in my previous test.
Iamge:  https://dl.dropboxusercontent.com/u/19882028/MF/17dBm%20RPI%20WSPR.jpg

The beacon is running now on 475.685 kHz.

73, Stefan/DK7FC


Am 18.03.2015 21:45, schrieb DK7FC:
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.
--=====================_17405047==.ALT--