Yaesu seems to be having trouble properly mounting the RF blocks
on the heat sinks. I think the small heatsink and fan combo would
work if a proper bond is made. There just not much room for error
in modern radios. The FT 5100/5200 uses a SAV-24 for the VHF PA.
It's quite expensive from Yaesu. RF Parts has an SAV-18 with the
same ratings, but about 2db less gain. Cost was about one half. I'm
getting 40-45 watts out. Make sure there is absolutely no
contamination or tarnish on either surface before carefully applying
a very thin layer of high-quality heat-sink compound to both surfaces. Then
make sure the mounts are properly torqued. RF Parts will provide
specs. It looks like some shops get a little sloppy here. Good
Luck. Dave WA0ZZG
AR
To: <yaesu@contesting.com>
> Date: Mon, 13 Apr 1998 10:29:47 -0400
> From: Daniel Senie <dts@senie.com>
> Organization: Amaranth Networks, Inc.
> To: "Mills, Chuck" <millscl@msx.upmc.edu>, yaesu@contesting.com
> Subject: Re: [Yaesu] FT8100R Receiver Stage going?
> Of 3 FT-8100R radios I own, one went back at age 3 months for a $350
> repair (covered by warantee) that involved a new PA module, new VCO
> components, etc. Another one has a significant deviation in one circuit
> from the schematic, and nobody at Yaesu will tell me why. I intend to
> undo that change at some point (it's in the mute circuit).
>
> I also own two FT5200s, one of which has blown up its PA twice. The
> first time it cost me a bundle to have Yaesu fix it, and I haven't sent
> it out again. I may just write it off.
>
> Yaesu likes to build these tiny radios with fans on the heat sinks, but
> doesn't know how to make those fans keep working. The 5200 works off of
> a temperature sensor, and the blown 5200 doesn't spin its fan no matter
> how hot it gets.
>
> Bottom line, I don't intend to consider Yaesu next time I buy mobile
> rigs, and generally recommend friends look at other brands. And look for
> radios that use proper thermal design with heat sinks, not fans.
>
> Dan
>
> Mills, Chuck wrote:
> >
> > Hi there....
> > I have an FT8100R that seems to have burnt out part of the receiver
> > stage. Has anyone seen this happen on their rig? One day, while
> > transmitting, I smelled componets burning, stopped transmitting and
> > noticed that I had almost no receive
> > whatsoever. Has this happened to anyone???
> >
> > Also, high SWR seems to cause a sticking in TX mode on 2m. Has
> > Yaesu owned
> > up to a fix on this problem?
> >
> > Thanks,
> > Chuck / W3YNI
> >
> > --
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> > Submissions: yaesu@contesting.com
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> > Problems: owner-yaesu@contesting.com
> > Search: http://www.contesting.com/km9p/search.htm
>
> --
> FAQ on WWW: http://www.qsl.net/k7on/yaesu.html
> Submissions: yaesu@contesting.com
> Administrative requests: yaesu-REQUEST@contesting.com
> Problems: owner-yaesu@contesting.com
> Search: http://www.contesting.com/km9p/search.htm
>
>
--
FAQ on WWW: http://www.qsl.net/k7on/yaesu.html
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