K3 Low Pass Filters

[Pete Smith N4ZR]

I'm planning to use my K3's RX antenna loop with a splitter to feed
signals also to my QS1R.  W4TV warned of the impact of the TX low-pass
filters on received signals.

 From some crude experiments, it appears that the low-pass filters are
grouped, rather than being  strictly one per band.  It looks as if there
are LPFs for 1.8, 3.5, 7, 10+14, 18+21, 24+28, and 50 MHz.  I could not
find confirmation of this in either the manual or the Cady book, but it
makes sense to me.  Can anyone confirm it?

--
73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000 and
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[Pierfrancesco Caci]

>>>>> "Pete" == Pete Smith N4ZR <[hidden email]> writes:



    Pete>  From some crude experiments, it appears that the low-pass
    Pete> filters are  
    Pete> grouped, rather than being  strictly one per band.  It looks
    Pete> as if there  
    Pete> are LPFs for 1.8, 3.5, 7, 10+14, 18+21, 24+28, and 50 MHz.  I
    Pete> could not  
    Pete> find confirmation of this in either the manual or the Cady
    Pete> book, but it  
    Pete> makes sense to me.  Can anyone confirm it?

Page 4 of the schematics. The 40 m one also serves for those lucky enough
to have a 60 m allocation.


--
Pierfrancesco Caci, ik5pvx
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[Joe Subich, W4TV-4]

Pete,

> It looks as if there are LPFs for 1.8, 3.5, 7, 10+14, 18+21, 24+28,
> and 50 MHz. I could not find confirmation of this in either the
> manual or the Cady book, but it makes sense to me. Can anyone confirm
> it?

As I suggested previously, look in the schematics - page 4.  You will
see filters for 160, 80, 40/60, 20/30, 15/17, 10/12, and 6.

73,

    ... Joe, W4TV


On 5/8/2012 3:20 PM, Pete Smith N4ZR wrote:

> I'm planning to use my K3's RX antenna loop with a splitter to feed
> signals also to my QS1R.  W4TV warned of the impact of the TX low-pass
> filters on received signals.
>
>   From some crude experiments, it appears that the low-pass filters are
> grouped, rather than being  strictly one per band.  It looks as if there
> are LPFs for 1.8, 3.5, 7, 10+14, 18+21, 24+28, and 50 MHz.  I could not
> find confirmation of this in either the manual or the Cady book, but it
> makes sense to me.  Can anyone confirm it?
>

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