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[SECC] cw and ssb filters

Subject: [SECC] cw and ssb filters
From: NQ4I@compuserve.com (Rick Dougherty)
Date: Tue, 18 Dec 2001 21:18:33 -0500
Its been going round and round and I need to wade in here and express my
opinion about the Ft-1000mp and how to filter it up......first off the
INRAD filters are hands down better than any stock Yaesu filter ...6 poles
vs 4 poles and 
much steeper skirts...so do all in your power to get rid of any and all
yaesu filters and get the INRAD's....

Secondly....SSB will be my first topic...the stock 2.4 khz filters are
pieces of junk...I have had INRAD's 2.1 and 1.8 
in radios side by side...the difference is night and day...the inrad 2.1
would be a great replacement for the stock yaesu 2.4....but enough on
this...the 1.8 is the only way to go for any serious ssb contestor...reason
is that it has really steep skirts and really rejects adjacent qrm...the MP
offers us the opportunity to recover some of the audio
that could be lost with this filter combination by the menu 8.9....go to rx
ssb lsb and usb and put in approx -.120 for 
both lsb and usb and the audio will be fairly decent...you could also crack
the IF shift knob...but this is far better...I use the 1.8 in my daily
operations and am now totally used to its sound...

Thirdly...CW is now the topic....to properly filter up the MP...do the
following...order the pair of 400 hz filters and install them in the 500 hz
slot...remove the Collins 500 hz mechanical filter and put it in the sub
rx....does a nice job there and its not too narrow...it has shallow
skirts...now if you want to really captialize on the radios performance
....put a pair of 250hz filters in the narrow slots...you can operate on
the low bands with the pair of 400 hz filters and 90% of the time be really
happy...but when KC1XX decides to drop in really close then bring on the
250hz's and 
watch him disappear...what also happens is with the narrower filter the
signal to noise ratio improves too...

Now let me also discuss a few other 1000MP things...the 70mhz mod is not
worth the $55 that they are charging now for it...it totally destroys the
third order intercept figures...that means that when a loud nearby signal
will capture your rx passband from just out side the filter passband...I
don't see why anyone would want to lower their ability to operate in a
crowded band and have nearby signals over-ride what they ultimately want to
hear...I saw in a test at W8JI on 2 of my MP's that we lost close to 30 db
of third order intercerpt cabability....

The resistor/capacitor agc mod is worth doing....

But of all the mods out there the key click mod is the most important...Tom
W8JI observed 20-30 db of reduction of keyclicks on my two mp's that he
modified...this mod makes this radio possibily the most contest prone radio
since the proverbial TS-930's .....you can't get any more bang for the buck
than a well filtered MP.....

I am a power user of the MP myself...I own 4 of them and will probably get
a couple more in the coming years...the radio is almost bullet-proof...we
have used 2 on the same band with out any problems at all....and I am
advocating them for the future NQ4I Multi-Multi's in the future.... 

de Rick


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