Yo! Troy:
Monday September 02 1996 21:36, Troy H. Cheek wrote to Jonathan Guy:
 TC> For that matter, the only manual he had was for the 2006.  Claimed that
 TC> there were so few differences between the 2004/5/6 that it wasn't worth
 TC> the effort to track down the correct manual.  What I tried from the 
manual
 TC> worked, so I can't argue that...
I'll attest to the fact that the PRO-2004/5/6 are all from the same mold and 
die.  There ARE plenty of subtle differences in the electronic designs, and 
of course, the physical layouts can differ dramatically.  But they are the 
same,
more or less.
Using the PRO-2004 as a reference and neglecting the physics:
1.  The PRO-2005/6 have an extra IF filter for the AM section.
2.  The PRO-2005 has a physically redesigned Logic/CPU Board, but appears
    almost identical electrically to the 2004.
3.  The PRO-2006's Logic/CPU Board looks like the 2005's, but has a number
    of minor electrical differences.
4.  The PRO-2006 uses a CMOS bilateral switch in series with the SQUELCH
    hysteresis loop on the NFM chip as an interesting compromise to our
    "squelch mods".
5.  The PRO-2005/6 have a different sort of WFM section, though it looks
    a lot like the 2004's.
6.  Each of the PRO-2004/5/6 uses an entirely different CPU, though the
    pin functions in each are identical.  I have sucessfully installed a
    PRO-2006 CPU in a PRO-2005; changed the Clock Resonator from 7.37 MHz
    to a 2006's 12 MHz, and it worked as a PRO-2006!  This makes one wonder
    if a PRO-2006 CPU can be laid out on a header of some sort, and then
    wired to the PRO-2004's CPU DIP pinout (after removing the DIP CPU,
    of course.)  I haven't had the "hair" to try this, yet.
There are minor receiver section differences from one to the next, but in 
essence, once you've seen one, you've seen all three.
What's more, the PRO-2035, PRO-2042, and the PRO-43 are all closely related 
to the PRO-2004/5/6 series, though there are substantive differences in 
physics and electrics here and there.  Still.......they're much alike.
Bombshell?  The PRO-34 handheld and the PRO-2022 base are electrically clones 
of each other.  One and the same.  The PRO-37 is too, except for a different 
CPU, clock, and some very minor differences here and there.  I believe the 
PRO-32 handheld and the PRO-2021 base are clones of each other, too.
Bill Cheek | Internet: bcheek@cts.com | Compu$erve: 74107,1176
Windows 95 Juggernaut Team | Microsoft MVP
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