I have a Keithley digital microvoltmeter which has a fault in one of its red LED display digits. The part is a Fairchild FND561 which is no longer available. I am having trouble finding a replacement and would appreciate any suggestions in finding an equivalent, though I'd reckon siomething should be available.
The display is the leading digit which displayes +/- 1. It is a 13mm DIP package.
As it has both the 1 and the sign of the signal, its absence makes the meter of limited use! Any suggestions greatly appreciated. Dave