I'm trying to determine what cause brand new 4116 chips from Jameco to fail immediately on the intial power up. I had found that after my Rev.0 sat for 8 years, when I powered it up the PSU had died. I had a spare Apple IIe Astec PSU so I installed it. I reseated the CPU and many of the other chips, but not all. I had all good voltages and all good clock signals.
On power up, it beeped on Reset and gave me a Monitor prompt. Running the memory test indicated some bad memory. I reseated all 48K memory wearing a anti-static wrist strap and the Apple plugged into a ground outlet and OFF. Bad memory was still indicated in banks D & E.
I purchased an UNO based memory tester and found all Block C memory tested good, but all Block D & E tested bad, totally bad. I ordered new 4116-15 from Jameco and installed them as described below.
I am no newcomer to adding memory in Apple II's although it has admittedly been many decades since my last time. Any insight into culprits is appreciated.
Methodology used:1. Apple II plugged into grounded outlet with power off for days.
2. Grounded myself sitting in front of Apple and put on my grounded anti-static wristband.
3. Memory was removed from the anti-static chip carriers and placed on a sheet of grounded aluminum rack panel.
4. Memory was loaded into a chip insertion tool and plunged into each socket.
5. the 16K jumper blocks were checked and tested for proper insertion
6. power was applied but the monitor memory test showed some memory failures.
7. powered off the Apple and waited 20 minutes, pulled the D & E 4116 and all but one tested bad (the first chip in bank E, E3 was good all others in D & E...BAD.
8. the first chip in bank C, C3 tested good. I didn't test the remainder of back C as yet.
Any ideas? Thanks in advance.