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TomL_12953
05-24-2010, 01:35 AM
My ACR is only reading +3.9V on the UART when it should be +5V. Does my power supply need adjusting? If so what's the best method? Do I remove all the cards and measure the bus lines? I don't want to blow all my boards!

Tom Lake

marty
05-24-2010, 01:49 PM
Hi Tom;
Check the Regulator on the Board that has the Uart on it... (88-sio) it should be something like a 7805 or a 78M05... Also you could have a BAd Power Cap on either side of the regulator..... Also check the other Ic's on that Board, if the power is good on them , then check that you don't have a bent pin on the uart, or a short on the power pin to something else....
THANK YOU Marty

peroja
09-07-2010, 06:36 PM
Hi Tom;
Check the Regulator on the Board that has the Uart on it... (88-sio) it should be something like a 7805 or a 78M05...
THANK YOU Marty


7805 is correct