14 Jun
2007
14 Jun
'07
2:56 a.m.
1820-2075 = 74LS245 (that has 20 pins, surely)
1826-0210 = LM361
1820-1197 = 74LS00
1820-1216 = 74LS138
1820-1202 = 74LS10
1820-1112 = 74LS74
1820-1422 = 74LS122
1820-2058 = MC3448L (HPIB buffer chip)
1820-0325.= MC815P
Wow!!!! Thank you!!
This really simplify the task to understand what's wrong and replace a chip
if needed.
I'm just curious about two things:
first, are this hp house codes generic (i.e. valid for any product), or are
they related to this controller only?
second, where do you find these valuable informations?!?!? ;-))
I've
checked almost all points in the circuit, and I didn't find any -Ve
supply. Also, PSU only gives +5 and +12 volt.
Yes, but if the -ve supply circuit
has failed, you won't find it :-) I am pretty sure I have one of these, or something
closely related. If
you get stuck, I can be convinced to find it, pull the covers and do some
tests.
Ok, I'll let you know.
In the meantime, maybe I've found a complete service manual for the drive.
I'm waiting for it.
Thank you.
Roberto