[TenTec] Broadcast Interference Fix for the Corsair II

[Joe]

Thanks for that information Rick. That certainly is an option and I will do 
that if I cannot find out how to get this done without having to take the 
rig completely apart. I am thinking that there must have been several people 
who have implemented  Rick's (now W6NIR) fix. I am listening this morning 
and there is no BC interference, but I still hear a lot of hash. It all 
depends on band conditions. I gotta get rid of it.

Joe
----- Original Message ----- 
From: "Rick - DJ0IP / NJ0IP" <Rick at DJ0IP.de>
To: "'Discussion of Ten-Tec Equipment'" <tentec at contesting.com>
Sent: Monday, September 19, 2011 6:11 AM
Subject: Re: [TenTec] Broadcast Interference Fix for the Corsair II


> Of course there is another way to fix the problem without digging into the
> rig, but it's not exactly cheap.
>
> Dunestar makes a highpass filter, model HPF-400 which you can simply 
> insert
> in the antenna line, right at the transceiver. This external HPF will drop
> the signal level of the disturbing broadcast station and can be left 
> inline
> all the time, but it will cost you $99 plus shipping.
>
> For more info, see: http://www.dunestar.com/model400.htm
>
> 73
> Rick, DJ0IP
>
>
> -----Original Message-----
> From: tentec-bounces at contesting.com [mailto:tentec-bounces at contesting.com]
> On Behalf Of Joe
> Sent: Monday, September 19, 2011 4:14 AM
> To: TenTec Discussion
> Subject: [TenTec] Broadcast Interference Fix for the Corsair II
>
>
> Below is a posting I was so pleased to find in my search to find a 
> solution
> for Broacast Radio Interference and hash on all bands of my Corsair II. I 
> am
> anxious to try this fix but I the task of getting to the transistor Q2 
> seems
> to be almost impossible. I want to talk to Rick, WA6NCX, but I have not 
> been
> able to get up with him. Failing that, I would like to talk to someone who
> has completed this fix. I fear that if I am not careful here I will do
> something that I will regret. I would appreciate any help.
>
>
> Joe, N4YG
>
>
> WA6NCX posting 24 Aug 2000Subject: [TenTec] Broadcast Interference Fix for
> the Corsair III heard  tremendous hash on 160 - 40 meters whenever I 
> hooked
> my Corsair II  to
> a big 80-meter full-wave horizontal loop.  The problem was traced to
> overload of
> switch transistor Q2 on the 80969 LPF-TR board.  The transistor junctions
> were
> rectifying a strong local BC station (putting over a volt of rf into the
> receiver!), whose
> signals passed right through from the antenna to the SWR detector and xmtr
> LPF's,
> through the TR switch diodes and then into the Q2 collector without any 
> help
> from
> the rig's BC-reject high-pass filter network (the transistor is connected
> *before*
> the high-pass filter).
>
> After fooling around with a few false starts (which TT helped with, but
> didn't solve),
> it dawned on me that the fix is to connect the Q2 collector *after* the BC
> band high
> pass filter network, so that the strong BC station signal is greatly
> attenuated before it
> gets to the Q2 collector.  So all I did was cut the trace to the Q2
> collector and run a
> short wire from the Q2 collector to the output of the BCB reject high-pass
> filter,
> right at the "RX" connector on the 80969 circuit board (at the junction of
> C7, L9,
> and L10).  This fixed the problem completely -- no more hash and nice 
> quiet
> reception
> on 160 through 40 meters.
>
> -- Rick   WA6NCX
> remler at juno.com
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>