I recently purchased a Timewave DSP-9 audio filter. It's an amazing little
box. The DSP-9 CW filters have RAZOR SHARP skirts. Signals simply vanish
the moment they are outside the passband. Awesome.
I had one gripe with the unit. The 600 and 750 Hz CW filter center
frequencies the device was programmed with are too high for hard-core CW
DXing. A call to Timewave revealed an "undocumented feature" which allows
the center filter frequencies to be shifted down to 400 & 500 Hz, a big
(1) Remove the DSP-9's rear panel.
(2) Locate the three miniature sets of "prongs" (don't know what else to
call them) poking out the rear of the circuit board.
(3) The #1 prongs come from the factory shorted. Leave them alone.
(4) Add a computer-style shorting strap to the #2 prongs.
(5) Your DSP-9 now has selectable 400 & 500 Hz CW center frequencies.
>From email@example.com (Tim Pearson ) Sun Nov 21 23:22:55 1993
From: firstname.lastname@example.org (Tim Pearson ) (Tim Pearson )
Subject: KU4J SS SCORE
Only had opportunity to operate about 17 hours.
Class single-op high power
Q's SEC total
1228 77 189,112
Clean sweep! Got 3 VE8's...got last section sunday morning when KP4 called
>From Jim Reisert AD1C 20-Nov-1993 1129 <email@example.com> Sat Nov
>20 16:25:59 1993
From: Jim Reisert AD1C 20-Nov-1993 1129 <firstname.lastname@example.org> (Jim
Reisert AD1C 20-Nov-1993 1129)
Subject: CT bug?
------------------Reply to mail dated 20-NOV-1993 04:59:25.69------------------
I brought this up with Ken this week. We seem to think CT still gives
country credit for /MM QSOs, contraary to what K3EST published heere a week
or two ago.
Ken has had this on his plate for 5 years, maybe he needs to be nudged
Fortunately, not too many rare DX stations are /MM during the contests.
73 - Jim AD1C