[Argonaut_USERS_Group] Re: Cascading Filters

[NJ0IP]

Perhaps I don't understand the question, Jim.

I didn't really have to change much.

I bought an XF9-B 8-pole SSB filter.
It was about 1 sq. inch.
I removed the 4 crystals and associated parts from the 505's SSB Generator
board.  My first board had the crystals soldered directly to the SSB board,
not to a piggy-back board. The XF9-B didn't quite fit so I relocated
(physically, not electrically) a few of the board's other components.
Afterwards I determined that I needed to change the LO crystal on that board
as well.  I replaced it with one designed to match the XF9-B.  Then I
aligned the USB, LSB, and CW frequencies according to the procedure in
manual, but modified the frequencies of course to correspond to the new
center frequency.

I didn't have to do any modification to any other parts of the 505's
circuitry.  It was plug and play once I made physical room for the filter
and performed the frequency alignments.

73
Rick

-----Original Message-----
From: argonaut_users_group-bounces at mailman.qth.net
[mailto:argonaut_users_group-bounces at mailman.qth.net] On Behalf Of JAMES
HANLON
Sent: Thursday, January 13, 2005 8:36 AM
To: argonaut_users_group at mailman.qth.net
Subject: [Argonaut_USERS_Group] Re: Cascading Filters

Rick wrote:

> In my 505 and my 509 (many years ago), I replaced the 4-pole crystal 
> filter
> with an 8-pole filter.

You've peaked my interest.  I have a 505 that is working well.  What did you

do to replace the filter?  I'd like better selectivity for CW.

Thanks,

Jim, W8KGI 
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