| Author |
Message |
    
Adshar64
| | Posted on Friday, May 30, 2003 - 3:34 am: | 
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The other day while doing some work on the 2000 I found two spare
crystals I had in my parts bin that I had from a extensive grant mod
exercise i had done years ago.I already had a three position xtal
switch in there setup for 40 up and 40 down.With the pll mods done
there was a lot of overlap. These other xtals I had cut years ago
were designed to meet bands at the edge of the pll mod freq range
giving ~360 channels. So with nothing to loose I fitted these xtals
and all went well, only I found I had a 30kc gap between the three
ranges ie bottom xtal went from 25.555 to 26.785 middle 26.815 to
28.045 and high range 28.075 to 29.305. I had 10kc down and 1kc up
on the slide, which I though was conservative, as I have a
superdiode in there with inductor. Slide mod was done on radio in
the states before I got it and I never checked it really. Just
changed the varactor-diode etc. I checked the voltage on varactor on
up tune and I only had 4.2v on the varactor. Checked it out and R174
was still in the way I bypassed along with D51 to get full volts ie
8.2v at varactor on high tune. Now we were talking had 20 kc slide
there. Added another inductor and it must have been a mother because
on LSB centre and lower xtals I get ~120kc slide down and ~70kc down
on usb.On the top xtal on lsb I get 500kc slide down, slippery xtal
that one. Yes Im not kidding. I have left it like that and all modes
and bands are set to align in normal clarifier position. Which is 4
oclock course and 12 oclock fine with 3kc upslide available. Never
seen slide like it before, and those gaps are definitley gone.The
control is ok going down the first 30kc but get damn fast in tune
rate after that. But is achievable to set with fine tune as well.
The pot mod was all done ok strange how the previous owner or tech
missed that OH well. |
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