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AR-1000 Reset Procedure
=======================
- A small Philips screwdriver
- A soldering iron (30 W max)
- Remove the antenna
- Remove the batteries
- Remove the tuning, volume, and squelch buttons
- Remove the back cover (4 black screws), and disconnect it from
the rest
- Lay the unit flat on the table, keyboard and display below,
antenna connector away from you
- Unsolder the black wire from the lower right corner of
the upper board
- Unsolder the brown wire from the upper left corner of the same
board
- Remove the 3 screws that hold this board
- Pull GENTLY this board out of the upper panel (volume, squelch,
and tune rods come with the board - not the antenna connector)
- Unsolder the black wire from the upper left corner of the middle
board
- Unscrew the 3 copper columns that hold this board
- To get a better access on the lower board, you may wish to remove
some of the connectors that link the upper and middle boards to
the power supply board (the one that hides the speaker) --- don't
forget to take note of which connector goes where !!!
- Now take a look at the lower board. It looks like this :
(X) green led
+--------------------------------------------------------+
| |
| LCD display |
| |
+--------------------------------------------------------+
+-----------------+
| NEC |
| chip |
| D75308GF651 |
+-----------------+
o (A) o
| |
R1 R2
| |
o o
+---------------+ +--------+
| | | diodes |
| | +--------+
| |
| Hitachi chip | +--------+
| HN58C65FP-25T | | diodes |
| | +--------+
| |
| | +--------+
| | | diodes |
+---------------+ +--------+ (B)
- Solder a piece of wire (wrapping wire is a good candidate)
between points (A) and (B).
- Reconnect ALL wires (solder unsoldered wires and connect dis-
connected ones)
- Place batteries back
- Turn unit on : the display should be blank.
- Now type the following :
BANK
1 PROG 8 LIMIT 49.995 SEARCH 561.225 ENTER
2 PROG 50 LIMIT 107.995 SEARCH 561.225 ENTER
3 PROG 108 LIMIT 169.995 SEARCH 561.225 ENTER
4 PROG 170 LIMIT 296.995 SEARCH 561.225 ENTER
5 PROG 297 LIMIT 600 SEARCH 251.575 ENTER
6 PROG 805 LIMIT 1109995 [down arrow] 251.575 ENTER
7 PROG 1110 LIMIT 1300 [down arrow] 561.225 ENTER
- Turn unit off
- Unsolder the piece of wrapping wire
- Mount the unit back (wires, connectors, screws...)
- Turn unit on : it should be working !!!
DO NOT TRY THIS BY YOURSELF IF YOU DON'T FEEL CONFIDENT ABOUT
USING A SOLDERING IRON ON SUCH A MINIATURIZED DEVICE !!!
DON'T FORGET THAT, IF YOU FAIL, THE WARRANTY WILL BE VOID !!!
Now, let's relax. From the programming procedure, it is obvious
that you enter 7 sub-bands in the unit :
8 to 49.995 MHz
50 to 107.995 MHz
108 to 169.995 MHz
170 to 296.995 MHz
297 to 600.000 MHz
805 to 1109.995 MHz
1110 to 1300.000 MHz
These are the values for the AR-1000 as sold in France. The values
may be different for the units sold in Northern America (there may
be other gaps, especially for cellular phone frequencies).
I don't know what the following parameters (561.225 and 251.575)
mean. I guess they indicate which RF subcircuit, which step, and
which modulation mode to use. Anyway, since the sub-bands limits
appear so clearly, it might be fun to experiment. See what I mean ?
But, if we are to experiment, let's make things easier. Instead of
dismounting-soldering-programming-unsoldering-mounting the unit each
time, let's solder a 5" piece of wrapping wire to point (A),
a 5" piece of wrapping wire to point (B). Now we have 2 free ends :
let's solder a microswitch to them. We can glue the microswitch at
the bottom end of the unit, near the power supply board. Resetting
the AR-1000 is now much simpler : just open the unit (4 screws),
flip the switch, turn the unit on, reprogram it, turn it off, flip
the switch back, close the unit.
First of all, if you replace the first "8" with "0.5", you get an
AR-1000 with coverage extended down to 500 kHz. This may not work
on older units. My unit didn't let me program any frequency lower
than 0.5 MHz, or higher than 1300 MHz. Anyway, my aim was to try
to get rid of the 600-805 MHz gap. I tried the following sub-bands :
0.5 - 29.995
30.0 - 219.995
220.0 - 409.995
410.0 - 599.995
600.0 - 904.995
905.0 - 1209.995
1210.0 - 1300.000
To choose these values, I made the following assumptions : the
original values never exceed a 190 MHz span for the "561.225" series,
and never exceed a 304.995 MHz for the "251.575" series. I was careful
not to exceed these ranges, because of the necessarily limited span
of the internal VFO.
These values did seem to work, since I was able to hear some TV signals
near 620 MHz, that is, in the previous gap ! However, when I programmed
some search banks, it sometimes refused to search, even on "authorized"
frequencies (around 450 MHz). And, since there is nothing but TV
channels between 600 and 805 MHz (at least in France), I restored the
original values (except for the 0.5 MHz lower limit).
Now, if you find something interesting, please keep me informed !
Lionel ANCELET
BIX : lanc
CompuServe : 71641,1340