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Procedure to re-program the IC-751 or IC-745 RAM board
(in unfortunate event of battery replacement errors or battery failure)
compiled by VU2SBJ, Sri, Manipal, India
It is a well known fact that the RAM boards in some of the older ICOM radios have in them have volatile
memory contents which need a lithium battery backup. The data in this RAM retains as long as the battery
works fine. Usual life of this factory installed battery is between 7 to 15 years, depending on the working
and storage conditions of the radio. There is no evident problem if the battery is replaced in time. You could
replace the battery by using the procedure mentioned in this Icom URL :
http://www.icomamerica.com/support/documents/ram_card.html
However, during replacement, care should be taken to maintain the supply to the RAM by another parallel
battery source while the old battery is being replaced. In any unfortunate event of battery failing before you
decide to change it, or you mess up the connections or something while you are changing it, the content
inside the RAM is wiped off, and your radio is no longer in working condition. It does not work at all, and
the display just reads blank or 0.0000 or sometimes junk characters..
There are various alternatives from here on. You could either get board replacements manufactured by few
hams that have non-volatile memory on them, or get an Icom dealer to do the programming for you after
battery replacement, but both alternatives are pretty expensive.
If you are a little bit of a homebrewer yourself, this following procedure should help you get he radio
working and get you back on the band easily. I have done this, and it seems to be working fine for the IC745 and a IC-751 I re-programed.
First you need to build a simple interfacing board on which you can plug in your RAM board and connect
the interfacing boad to the parallel port of your PC. Using the software utility N2CBU made originally for
the Icom's R71 RAM board modification, you can then program the data content into your IC-745 or IC751 RAM boards. All boards are essentially the same, and also the programs for the 745 and 751 are
compatible.
You could download the file ICOMRAM.ZIP from N2CBU's web page. This zip file contains the RAM
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Module Programming Utility and also the schematics and procedure for the interfacing circuit.
The URL for downloading this file directly from here is
http://www.geocities.com/emailsrikanth/ham/icomram/ICOMRAM.ZIP
To visit N2CBU's page please go to http://www.geocities.com/n2cbu/
However the file to use for the IC-751 or IC-745 is not available on N2CBU's site. I have it HERE
You would need to run N2CBU's program, load this above file and then write it on the RAM you are
programing. Make sure you are using the right parallel port address in the program - you could select the
port address in the program (whatever address the PC has used - if you need to change any settings in your
PC's parallel port settings, u could set it in the SETUP menu before it boots, by using the DEL key just as
the PC switches on).
Please note that this RAM data is from a IC-745. It has worked well for both 745 and 751 for me. However,
i cannot guarantee any accuracy of this procedure. It worked for me, so it may work for you as well!
I hope this is useful.
Hope you get your radio up and running - If you need assistance of some kind, please contact me at
vu2sbj@yahoo.com
If nothing works, you could send the RAM board to me, I'll program it for free, but you pay for postage.
best 73
Sri, VU2SBJ
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