Hmmm
Don't recall a FET in a metal case. There is a MOSFET (4 legs) in a metal
case which is a mixer and also another transistor Q1 in a metal case. I
have touched the top of both of these and it doesn't effect the noise... So
maybe I have a different board or parts on mine then you do. None have
ferrite beads on them either. Wonder if you might have made a mistake in
your recollection and that TT added beads to the Mosfet Mixer Q2 (3N201) on
board which is a small metal case device. The other metal case is a
standard TO-3 case size....
Maybe I need some beads on that 3N201...
Steve
----- Original Message -----
From: "denton" <denton@oregontrail.net>
To: <tentec@contesting.com>
Sent: Wednesday, September 03, 2003 6:33 PM
Subject: Re: [TenTec] Noisey Corsair II
> My Corsair II has a noisy fet or transistor on the if-af board. It is a 3
> legged device and has a little ferrite cap on two of the legs. One can
> locate the noise source by simply touching the metal cap with the rig
> running. I simply put on an short 6 inch piece of insulated wire around
the
> metal cap and then ran the wire along the side of the main corasir's case
to
> drain off the noise.
> ----- Original Message -----
> From: "Steve" <sswhite@mchsi.com>
> To: <tentec@contesting.com>
> Sent: Wednesday, September 03, 2003 1:55 PM
> Subject: [TenTec] Noisey Corsair II
>
>
> > I have been enjoying a new Corsair II and have just recently re-built
the
> PTO and it is now smooth as silk, it even approaches my FT-1000MP VFO in
> terms of smoothness.
> >
> > I have noticed that the Corsair II has noticeably more background noise
> than my Omni-D has and I began looking around for the source of it. It
> appears that it is coming from the PBT board since. When I disconnect the
> ouput of the PBT board which goes to the IF board it quites down very
well.
> Of cousre some background noise is to be expected and all of my comments
> relate to no antenna connected. When I disconnect the input to the PBT
> board it also has a small drop in background noise, but no where near as
> dramatic as when I disconnect the PBT board from the IF stage. It appears
> to me that the noise source is really the PBT board.
> >
> > So the question is does any know of any historical problems with noisey
> PBT boards or what could be causing this. As you know the PBT board has
two
> mixers on it and I suspect one of those is the culprit since they can be
> noisey at times..
> >
> > Steve NU0P
> > _______________________________________________
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> > http://lists.contesting.com/mailman/listinfo/tentec
> >
> >
>
>
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