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Old 08-30-2009, 03:19 AM
marty marty is offline
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Join Date: Jun 2007
Posts: 118
Talking 60 hz

Hi Tom;
Before I replaced the Power supply in my Altair, with Switchers, it Did Have a line going to the Power Supply, which if I counted and rememberd right was pin 55... Since I don't plan on having and at this point don't have a use for the RTC, it was no problem getting rid of it.... Two suggestions --- 1. check what kind of an input the RTC is looking for, such as you might be able to tap on to a 6.3 volt line , which would be the center tap for a 12.6 volt transformer, if it has one, other wise go thru a SMALL Cap for the 60 hz signal. 0r 2. Yes you could possibly use something from the CPU Clock, but it has to be divisible down to 60 hz or I assume it won't work right. You could find a crystal or a ttl module type of crystal (can't think what its proper name is) that looks like a 14 pin Ic only with 4 pins, one on each corner. get something that will divide down , like 60mhz, 30mhz , maybe a 15mhz, if you can find it a 60, 30, 15 khz and keep dividing it down till you get what you need. I have used 74393's for my divide circuits... I have a board that I Wire-Wrapped with Sockets that I can put in different frequency modules and then pick how far down the divide chain I want, thru a number of sockets , and then out to a 74LS04 and to a Led and then out , for me to use as I wish..
THANK YOU Marty
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