[amsat-bb] Re: Fixed! Re: Landwehr 70cm preamp

[Bill Dzurilla]

Those Landwehrs are great preamps.  I had an issue similar to Mark's, except it was the transmit side of the Tohtsu relay that had the problem.  I could receive fine but had high SWR during TX.  Unlike Mark, I did risk a shot of spray, which didn't cure the problem.  But then ran a sheet of paper between the contacts and it has worked fine ever since.

73, Bill NZ5N

> Subject: [amsat-bb] Re: Fixed! Re: Landwehr 70cm preamp
> device
> To: amsat-bb at amsat.org
> Message-ID:
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>     
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> 
> FYI, parts for the Landwehr pre-amps 
> 
> 
> 
> 
> Ted at Radio DAN still?carries?replacement Mitsubishi
> MGF1402 GaAsFET (discontinued) 
> 
> http://www.radiodan.com/ted_stuff/landwehr.htm 
> 
> 
> 
> RF Parts lists the Mitsubishi MGF series 
> 
> MGF1402 - was listed as $18.95 in 2007, currently (2011)
> you need to Call for Price. 
> http://www.rfparts.com/transistors_2SKand3SK.html#bf 
> 
> 
> 
> Check with K0KN ...?from an earlier AMSAT-BB posting -- he
> may have?extra ! 
> 
> http://www.amsat.org/amsat/archive/amsat-bb/200701/msg00021.html
> 
> 
> 
> 
> PC Electronics?carried the part in 2007, but they may have
> sold?their remaining stock. 
> 
> http://www.hamtv.com/specials.html 
> 
> 
> 
> GH Engineering (UK) 
> 
> http://www.ghengineering.co.uk/prices.htm#Mitsubishi 
> 
> 
> Greg 
> 
> w9gb 
> 
> ==== 
> 
> 
> 
> Date: Thu, 2 Jun 2011 08:59:54 -0500 (CDT) 
> From: n0jy 
> Subject: [amsat-bb] Re: Fixed! Re: Landwehr 70cm preamp
> device 
> ????????question? 
> To: "Mark L. Hammond" 
> Cc: K5OE 
> 
> I'm glad you shared this all here Mark, I have a 2M
> Landwehr that's been 
> cranking along since 1993 or so, I've never looked inside
> but this thread 
> is something I'll keep in case it gets flaky on me. 
> 
> 73, 
> Jerry 
> N0JY