The Collins filter is worth the effort only if you are still using
the original 3-pole filter. If you have already upgraded to the
8-pole filter, the improvement isn't worth it
The Collins filter has two big advantages over the original filter:
1. Very little leakage around the filter. Out of band attenuation is
quite high. The 8-pole is just about as good.
2. No ringing caused by noise pulses. All crystal filters 'ring' a
little bit when pulsed. The makes the mechanical filter appear to
sound different. It sounds tighter.
The installation of either the 8-pole or mechanical filter isn't easy
in the FT-900. It requires removing the receiver board from the
radio, unsoldering the 3-pole filter(use a BIG gun), and properly
positioning and soldering the new filter. If you don't get it
positioned right, you'll loose out-of-band attenuation.
Good luck and have fun! 73 Dave WA0ZZG
AR
To: <yaesu@contesting.com>
> Date: Wed, 27 Nov 1996 21:02:38 -0800
> From: Kyle Sandel <sandelkw@alaska.net>
> To: yaesu@contesting.com
> Subject: Re: [Yaesu] Info about FT900
> Digital Equipment wrote:
> >
> > Hi all:
> >
> > I have the FT-900 and I seem that the Collins filter makes really
> >a difference. Does anybody have some experience on this?
>
> SNIP
>
> Curious if the 900AT can be retrofit with the Collins filter? How much
> difference did it make?
> --
> Kyle Sandel, AL7J x-AL7QE
> sandelkw@alaska.net
> AL7J@KL7AA.#NAK.AK.USA.NA
>
> --
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>
>
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