PLEASE do not distribute this file yet.  It is a work in progress.
I'm asking for your feedback and help finding any obvious mistakes.
/It is not legal to listen to other people's telephone conversations/
/with radio and/or scanner equipment.  This modification is provided/
/for information purposes only, not as an attempt to encourage people/
/to commit illegal acts.  No warranty is offered or implied./
Troy H. Cheek's PRO-46 Mod for 'unmodifiable' models, v0.1  08-14-96
This mod will allow certain PRO-46 variants to access the 66-88 and
869-896 MHz ranges in 5 and 30 kHz steps, respectively.
While reading this mod you will get the impression that I think you're
an idiot.  Quite the contrary.  I think that *I'm* an idiot, and
decided to write a mod based on what I screwed up when I performed
this procedure myself.
The oldest PRO-46's could apparently be modified for direct entry of
any 800 megahertz frequency by removing one surface mount diode and
moving another.  As luck would have it, I didn't buy one of those.
The PRO-46's microprocessor was later modified so that the diode
change didn't work, but you could still use the scanner's test modes
to access one of the lost frequency ranges (869-896 MHz), and one
which I'm not sure the scanner ever received normally (66-88 MHz).  I
didn't buy one of those, either.
The PRO-46 was *later* modified so that even the scanner's test modes
wouldn't work.  Guess which one I bought...
Model No.:  20-305
Scanning Receiver PRO-46
FCC Id: AAO20-305AI
Date label: 10A3
This mod covers *this* particular variant, and re-enables the factory
test so that the 66-88 MHz and 869-896 MHz ranges are accessable
(after a fashion).
_Modifying the scanner_
0.  Before doing any work of any type on your scanner, make sure you
    have all your frequencies recorded somewhere.  With any work on
    the internals you risk losing your stored channels, and this mod
    actually requires it!
1.  Remove the battery pack, battery door, and antenna.  Unplug the AC
    adapter.  Place the monitor face down on a soft surface to avoid
    scratching the display.
2.  Remove the four black screws from the back of the radio (two are
    inside the battery compartment).  At the bottom of the battery
    compartment is a catch.  *Carefully* push and tug at the bottom of
    the two halves until you figure out how to work that catch without
    breaking it.  At the top the halves sort of hook together.
3.  Now we're going to separate the two large boards that are set one
    on top of the other.  Carefully insert a small screwdriver between
    the two boards next to the interconnect plug in the lower right
    corner.  Gently pry the top board up to separate it and set it
    aside.  If it doesn't come right up, check to make sure you're
    prying on the correct connector between the correct boards!
4.  Carefully unsolder the copper-coated plastic shield from the
    microprocessor and set it aside.
    *CAUTION!!!  Too much heat will damage the shield.*
5.  In the area you uncovered, there's a small board just up from
    centter.  It's about an inch side-to-side and a quarter-inch
    top-to-bottom and may be covered in some way.  The small board has
    five wires coming from it, four of them coming from the bottom.
6.  Of the four bottom wires, find the second wire from the right,
    (reportedly, this is usually a brown wire) and clip it close
    enough to the circuit board that you can resolder it if necessary.
    Wrap or secure this wire in some way so that it doesn't short
    something important later.
7.  Reassemble in reverse order.  You may choose not to replace the
    copper-coated plastic shield at this time.  Be sure to replace it
    once you're satisfied your scanner is still working properly.
8.  While holding down the 2, 9, and L/OUT keys, turn the power on.
    The scanner should now have values entered in the first 25
    channels (and scan them normally), with the remainder being clear.
    If it doesn't, try a few more times, then go back and double-check
    steps 5 and 6.  If it does, and everything else appears normal,
    now would be a good time to go back and replace that shield!
--- JetMail 0.99beta22
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