Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dk01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 122F738000092; Sun, 9 Oct 2011 04:50:53 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1RCp54-00052P-4R for rs_out_1@blacksheep.org; Sun, 09 Oct 2011 09:49:58 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1RCp53-00052G-Co for rsgb_lf_group@blacksheep.org; Sun, 09 Oct 2011 09:49:57 +0100 Received: from nm1.bt.bullet.mail.ukl.yahoo.com ([217.146.183.199]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1RCp52-0005YG-8n for rsgb_lf_group@blacksheep.org; Sun, 09 Oct 2011 09:49:57 +0100 Received: from [217.146.183.196] by nm1.bt.bullet.mail.ukl.yahoo.com with NNFMP; 09 Oct 2011 08:49:50 -0000 Received: from [217.146.183.203] by tm2.bt.bullet.mail.ukl.yahoo.com with NNFMP; 09 Oct 2011 08:49:50 -0000 Received: from [127.0.0.1] by omp1001.bt.mail.ukl.yahoo.com with NNFMP; 09 Oct 2011 08:49:50 -0000 X-Yahoo-Newman-Id: 269216.35565.bm@omp1001.bt.mail.ukl.yahoo.com Received: (qmail 81906 invoked from network); 9 Oct 2011 08:49:50 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btinternet.com; h=DKIM-Signature:X-Yahoo-Newman-Property:X-YMail-OSG:X-Yahoo-SMTP:Received:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=FggyZEXshcVqW9I4ZZMT7aNsyExe94sve6FpO6R0ZQsELbtw2vaD9umzwlxzGjib6eZcyHir5JFIMrhRLyeS13i3elbkZT3Z7dSGKoPCgW3MEKi2sUqhECD0lgN42fJVgc50kRxr7z646vmmkOXVJUOYh5BF6zPDyEM64bfoVa0= ; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=s1024; t=1318150190; bh=iPZHpkXuZdTdubxX2IIEzu3wUXlcnfiam5TmDoYkmnk=; h=X-Yahoo-Newman-Property:X-YMail-OSG:X-Yahoo-SMTP:Received:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=5XXZh6Q6nmDdYCvyA2OzZ9fTZu7wLi+lJRY8xeXVGbLnORHD98XPoxMYQcU8rZA//OgkWXVEgLJaWy//WBaz+lRpmEuXBcLzZMaa3swNbaHYC7K/eLhj2lyQmUC6yROs56oGKD744gHcAlBnLbgcSN0VeQO1yFuDRhhqN1uljhs= X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: Sz1fNhYVM1n.or.JGU8OHyrGqQGyFgVcjV0BNcT0TFOwasz bDFNyZopShStxjeleb2y3X9FWTYi9CjFQDMBsknrmZ.iwxSdEiCbgYyp0psr .kKzPVCDNyQj4ouGSVu7ikHgNyVLQ5oszvKdiDa8zgVKxKvlm9EAAWWOxEO1 _Pdhv_BKQ3rPr8dtrB4lG3o5SWPb4Ba2TgiwMl.5hGsiX5uB8R7VL8XvZAji VjLyEyaioG9Vig7GlcelUmlQfK8HbQmZmB6GHuy8zaLeaGfjsXmuewb0hBjf tn9zbbbzspSFHGTSaMwcADKDfM5nAj6F9_XL1kPWdd763EGMu4Qhd3XGP0ZC ECx.LHhnDphJadtTuglpvGJ8DH.ETdLu8VxA_xpQAHZ17iyCmEjpDI4o5kO3 3yhrLr4YtEvbHpjlcyrWCDxG2rP0f7DqCM1_dD9Y_LcSEDTUmt.V_lQexxo9 1Mq4L4vgJpeH3wo4s X-Yahoo-SMTP: 9Y6mUHuswBAgnrOsukIiNdFDf95uy_Dz34nY1hlg2liKgYD952sjbg-- Received: from lindavideo (ken.h.wright@81.159.43.135 with login) by smtp822.mail.ukl.yahoo.com with SMTP; 09 Oct 2011 08:49:49 +0000 GMT Message-ID: From: "Ken" To: References: <4E9083DB.5090603@iup.uni-heidelberg.de> <4E909FCE.7060302@telus.net> <4E90A3F1.8080004@iup.uni-heidelberg.de> <4E90BD44.1060700@telus.net> <4E90C0CC.7070209@iup.uni-heidelberg.de> <1318148290.2129.YahooMailNeo@web29513.mail.ird.yahoo.com> Date: Sun, 9 Oct 2011 09:49:47 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6109 DomainKey-Status: good (testing) X-Spam-Score: 3.4 (+++) X-Spam-Report: autolearn=disabled,FORGED_MUA_OUTLOOK=3.36,HTML_MESSAGE=0.001,UNPARSEABLE_RELAY=0.001 Subject: Re: LF: Laser link... Content-Type: multipart/alternative; boundary="----=_NextPart_000_000C_01CC8668.C7CD67F0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: ** X-Spam-Status: No, hits=2.1 required=5.0 tests=FORGED_MUA_OUTLOOK,HTML_20_30, 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-SCOLL-SCORE: 0:2:506116480:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d007.2 ; domain : btinternet.com DKIM : pass x-aol-sid: 3039ac1db4054e91606d4358 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_000C_01CC8668.C7CD67F0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Stefan. I can only endorse Daniele's comments, I to worked on fibre optic = communications for many years, and the only safe laser is one that is = switched off, never wave a live optical fibre arround, you dont know who = is near you, Class 1 lasers were listed as safe, these are found in CD = players so I would use one of there from an old CD player, even so = please dont take any chances. What about a bright LED as a source? 73s. Ken. M0KHW =20 ----- Original Message -----=20 From: Daniele Tincani=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Sunday, October 09, 2011 9:18 AM Subject: Re: LF: Laser link... I too work with lasers daily (for fiber optics communications), but up = to a few mW only :-) Be careful with those laser guns, especially for eyes :-) Regards D. Da: Stefan Sch=E4fer A: rsgb_lf_group@blacksheep.org Inviato: Sabato 8 Ottobre 2011 23:29 Oggetto: Re: LF: Laser link... Thanks again Scott. Yes, the building should be stable ;-) We have a = working group here that works with that optical stuff all the time, they = surely can give me filters and further advice. They told me they tried a = 80W ERP laser into the sky, just for fun. Such things can be done on a = university, never ever in industry, one reason to work here ;-) 73, Stefan Am 08.10.2011 23:14, schrieb Scott Tilley: > Hi Stefan >=20 > I've created a wide-band audio link before using a laser. In fact, = I used it to bounce the audio I wanted to send off of a passive = reflector. Wideband and excellent fidelity is possible, just ensure the = object you are bouncing off is very stable otherwise you'll get = microphonics (useful if you want to hear what's going on somewhere else = :-)........ I strongly recommend the use of a very narrow band = interference type filter for the laser wavelength you are using, mount = this over the PIN diode detector... This way the system is usable day = or night without noticeable degradation due to sunlight. >=20 > 73 Scott >=20 >=20 > On 10/8/2011 12:26 PM, Stefan Sch=E4fer wrote: >> Thanks Dex and Scott, >>=20 >> Enough stuff to study now. The seconds page seems more useful for = me. >> Ok about that OT. >>=20 >> 73, Stefan >>=20 >> Am 08.10.2011 21:09, schrieb Scott Tilley: >>> Hi Stefan >>>=20 >>> http://www.k3pgp.org/laser.htm >>>=20 >>> I use his detector and modulator circuits for my system. >>>=20 >>> 73 Scott >>>=20 >>>=20 >>>=20 >>>=20 >>> On 10/8/2011 10:09 AM, Stefan Sch=E4fer wrote: >>>> LF, >>>>=20 >>>> Just thought about trying a LF RX in the forest and feed the = signal via a laser link to the building here. There is a good direct = view to several suitable places, a good 1000m distant from the city. A = simple laser diode, driven at 15 to 20 mA should work fine for some = hours when having a solar panel that charges during the day. You know = these small lamps for the garden with a solar panel, switching on = automatically when it gets dark... >>>> Just seen HA6PC at OE3GHB-grabber but nothing here or at DF6NM = (yes Mal, i know, you've all worked them in the past...). >>>> Pure AM is probably not the best choice, rather FM. >>>> Does someone of you has useful experiance of such a laser system = or even a ready to use circuit or some hints about a compact IC that = does the job? >>>>=20 >>>> No warnings about the danger of laser light please. >>>>=20 >>>> 73, Stefan/DK7FC >>>>=20 >>>> PS: Sri for beeing a bit OT >>>>=20 >>>>=20 >>>=20 >>=20 >>=20 >=20 ------=_NextPart_000_000C_01CC8668.C7CD67F0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Stefan.
I can only endorse Daniele's comments, = I to worked=20 on fibre optic communications for many years, and the only safe laser is = one=20 that is switched off, never wave a live optical fibre arround, you dont = know who=20 is near you, Class 1 lasers were listed as safe, these are found in = CD=20 players so I would use one of there from an old CD player, even so = please dont=20 take any chances. What about a bright LED as a source?
 
73s.
Ken.
M0KHW  
----- Original Message -----
From:=20 Daniele Tincani
Sent: Sunday, October 09, 2011 = 9:18=20 AM
Subject: Re: LF: Laser = link...

I too work with lasers daily (for fiber optics = communications), but=20 up to a few mW only :-)
Be careful with those laser guns, = especially for=20 eyes :-)
Regards
D.
Da: Stefan Sch=E4fer <Stefan.Schaefer@iup= .uni-heidelberg.de>
A: rsgb_lf_group@blacksheep.org=
Inviato: Sabato 8 Ottobre 2011=20 23:29
Oggetto: Re: = LF: Laser=20 link...

Thanks again Scott. Yes, the building should be = stable=20 ;-) We have a working group here that works with that optical stuff = all the=20 time, they surely can give me filters and further advice. They told me = they=20 tried a 80W ERP laser into the sky, just for fun. Such things can be = done on a=20 university, never ever in industry, one reason to work here = ;-)

73,=20 Stefan
Am 08.10.2011 23:14, schrieb Scott Tilley:
> Hi = Stefan
>=20
> I've created a wide-band audio link before using a = laser.  In=20 fact, I used it to bounce the audio I wanted to send off of a passive=20 reflector.  Wideband and excellent fidelity is possible, just = ensure the=20 object you are bouncing off is very stable otherwise you'll get = microphonics=20 (useful if you want to hear what's going on somewhere else = :-)........  I=20 strongly recommend the use of a very narrow band interference type = filter for=20 the laser wavelength you are using, mount this over the PIN diode=20 detector...  This way the system is usable day or night without=20 noticeable degradation due to sunlight.
>
> 73 = Scott
>=20
>
> On 10/8/2011 12:26 PM, Stefan Sch=E4fer = wrote:
>>=20 Thanks Dex and Scott,
>>
>> Enough stuff to study = now. The=20 seconds page seems more useful for me.
>> Ok about that=20 OT.
>>
>> 73, Stefan
>>
>> Am = 08.10.2011=20 21:09, schrieb Scott Tilley:
>>> Hi Stefan
>>> =
>>> http://www.k3pgp.org/laser.htm
>>>=20
>>> I use his detector and modulator circuits for my=20 system.
>>>
>>> 73 Scott
>>>=20
>>>
>>>
>>>
>>> On = 10/8/2011 10:09 AM, Stefan Sch=E4fer wrote:
>>>>=20 LF,
>>>>
>>>> Just thought about trying = a LF RX=20 in the forest and feed the signal via a laser link to the building = here. There=20 is a good direct view to several suitable places, a good 1000m distant = from=20 the city. A simple laser diode, driven at 15 to 20 mA should work fine = for=20 some hours when having a solar panel that charges during the day. You = know=20 these small lamps for the garden with a solar panel, switching on=20 automatically when it gets dark...
>>>> Just seen HA6PC = at=20 OE3GHB-grabber but nothing here or at DF6NM (yes Mal, i know, you've = all=20 worked them in the past...).
>>>> Pure AM is probably = not the=20 best choice, rather FM.
>>>> Does someone of you has = useful=20 experiance of such a laser system or even a ready to use circuit or = some hints=20 about a compact IC that does the job?
>>>> =
>>>>=20 No warnings about the danger of laser light = please.
>>>>=20
>>>> 73, Stefan/DK7FC
>>>> =
>>>>=20 PS: Sri for beeing a bit OT
>>>>
>>>>=20
>>>
>>
>>
>=20



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