Original AR1000 Frequency Range Modifications

In the September issue of Short Wave Magazine, (a British publication), there is an article that describes a method of increasing the frequency range of the original AR1000 (and Fairmate HP100) to cover the range of the newer models. It implies, but does not explicitly state, that this method will increase the range to include the lower 500 KHz range as well as the 600-805 MHz gap. 

The procedure involves a hardware reset of the microprocessor and a keyboard reprogramming of the scanning frequency parameters. The procedure is described below. Please note that I have not personally tested this procedure.

1) Remove the batteries. Disconnect the antenna and control knobs.
2) Remove the two screws in the battery compartment and the two screws at the top rear of the case.
3) Separate the case halves and then unplug the battery connector.
4) Remove the three brass Phillips screws holding the main PCB board in place. 
5) Carefully separate the PCB from the case. You may have to unsolder two ground straps in order to remove the PCB. Be sure to note where they attach.
6) Three brass studs that hold the second PCB should now be visible. Remove these along with a short wire near the top of the scanner.
7) Lift out the PCB. You should be able to see the 80 pin square microprocessor mounted on a third PC board. With the top of the scanner facing away from you, pin 1 of the microprocessor is at the top left corner of the chip. Count counter-clockwise down the left edge of the microprocessor until you locate pin 13. Mark it. At the bottom right edge of the chip is located pin 41. Count up the right edge until you locate pin 51. Mark it also. Double check these pin numbers to be sure you have correctly located pins 13 and 51.
8) Solder a temporary silicon diode between pins 13 and 51. It is better if you can connect the diode to the traces off the pins rather than to the pins themselves. Solder the banded end of the diode (the cathode) to pin 51. The anode goes to pin 13.
9) Reconnect the battery pack and turn on the scanner.
10) The display should be blank. This indicates that the scanner is ready to be reprogrammed (the hardware reset has now been performed).
11) Carefully enter the following sequence from the keypad. Command keys are shown within brackets (e.g. [Bank]). The down arrow key is shown as [V].

[Bank] 1 [Prog]  0.5 [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] 804.995 [Search] 251.575 [Enter] 
6 [Prog]  805 [Limit] 1109.995 [V] 251.575 [Enter] 
7 [Prog]  1110 [Limit] 1300 [V] 561.225 [Enter]

12) Turn off the scanner and disconnect the battery pack.
13) Desolder the diode and carefully reassemble the scanner. 

You should now have increased coverage. This information is credited to a representative of AOR UK.

Warning! This procedure has not been verified by me. If you perform this mod, please let me know how it turned out. Also let me know if you discover any errors or changes to this procedure. 

-Howard Bornstein
CS 76174,637

Short Wave Magazine is an interesting British magazine for SWL and scanner enthusiasts. 

Published by:
PW Publishing Ltd.
Enefco House
The Quay
Poole Dorset
BH15 1PP