The Willco Electronics No-Fail Memory for Icom Radios.
Sorry, The ICM-1024 is no longer available.
It didn't take long for someone to discover that a defective or dead
lithium battery on the memory board caused the radio to become inoperative.
The Icom module stores the radios 32 memories along with important data
that's used by the microprocessor's operating system. When the backup battery
fails, the memories and data is lost and the radio no longer functions!
I'm not implying that that your radio is defective and that Icom America
is responsible for any out of warranty repairs. Your Icom was manufactured
with the highest standards and designed to give you many years of service.
Icom selected the RAM based system to support multiple versions for
shipment to other countries. In the mid 80's, small inexpensive RAM memory
chips were available and before shpping the radio, Icom used computer controlled
programming fixtures to load the memory module with the appropriate version.
Back then 32K EPROM's carried a high price tag and low power, battery backed,
32K Random Access Memories were not available.
The lithium battery had a projected life expectancy of 10 years and
some batteries, at room temperature, can last longer than 15 years. Unfortunately,
Hams don't always operate their equipment at room temperature. Depending
on the environment, mobile or portable operation for example, the battery
life can be reduced.
The Willco ICM-1024B "NO FAIL" memory is a replacement memory module
that contains a Read Only Memory (ROM) that permanently stores the radio's
important data and a battery backed Random Access Memory (RAM) that stores
the radio's 32 (or 1024) memories.
In the mid 80's, Icom introduced the IC-745 transceiver and R71A short-wave
receiver. A few years later the IC-751 (HF), along with the IC-271 (VHF)
and the IC-471 and IC-1271 (UHF) transceivers were also available. All
six models were frequency synthesized and microprocessor controlled using
the same replaceable plug in memory module.
(TO VIEW THE PC BOARD, CLICK ON THE EYEBALLS)
MORE MEMORIES THAN YOU'LL EVER NEED!
The Willco ICM-1024B was originally designed for the R71A receiver and
a modification that connects the ribbon cable to IC pins on the radio's
Matrix Board is optional. The modification satisfies the memory requirements
for short-wave listeners by increasing the radio's memory capacity to 1024.
"Hot 250 H.F. frequencies are pre loaded in RAM (A Printed frequency list is included).
For Ham radio applications you probably don't need 1024 memories and
for you, the modifications aren't necessary. You can remove the ribbon
cable from the ICM-1024 and simply unplug the Icom memory module from your
IC-745, IC-751/A, IC-271A/H or IC-471A/H. Install our board and your radio
will operate normally.
FRONT
PANEL ACCESS
When the "mods" are performed on an R71A or IC-751/A, 32 banks of memories
can be accessed directly from the front panel without adding push buttons
or switches (the IC-745, IC-271A/H or IC-471A/H will require external switches).
The heart of the ICM1024 is a custom integrated circuit that handles memory
data and bank switching.
HERE'S
HOW IT WORKS
Even with Icom's IC-EX310 speech option installed, the SPEECH button
on your R71A or IC-751/A can be used to change banks. Simply rotate the
MEMORY-CH knob and select a memory. Then press the SPEECH button and the
bank, that corresponds to a memory number, will be selected. It's like
having 32 radios in one! Each time you press the SPEECH button on the IC-751/A
you step to the next bank. The FUNC button reverses the step direction
and the XIT/RIT RESET button jumps you back to bank 1.
The IC-745, 751/A and the R71A was not designed to handle 1024 memories.
Therefore, by storing a frequency that corresponds to a bank in channel
32, for example, you can determine which bank is being selected. 22 MHz
in memory 32 can indicate that bank 22 is selected. 11 MHz in memory 32
indicates bank 11 is selected.
EXTENDED FREQUENCIES
Icom used the RAM based design so that they can easily modify the radio's
frequency limits for operation in other countries. We took advantage of
that and extended the H.F. frequency limits from 10 kHz to 31 MHz, for the IC745 and IC751, we added the 60 meter band from 5.25MHz to 5.45MHz.
ONE SIZE FITS ALL!
By simply adding a jumper, the ICM-1024 can be installed in an R71/R71A,
IC745, IC-751/A or the IC-271A and IC-471.
You can contact us via E-mail at:
repair@willcoele.com
Home Office Tel: 815-463-9365