122

1745 12 Dec 67

Disk Read Error - Recoverable
Band = 205₈ TRK = 2 SA = 1503₈

SRR

1920 12 DEC 67

Disk Read error - Recoverable
Band = 205 Trk = 2 Sector = 1503₈

SRR

2200 12 Dec 67

[Emery?] maint started at 20:30

Parity errors found while running disk diagnostic.
In 1 case bit 15 got dropped after [?]
stored by CPU but before getting to [DP?] 167.
In another [area?] a AOJ? turned into a
OVO in a loop in the disk diagnostic
long enoug for a UUO trap to occur. said loop
was not run while disk was transfering. Both in core.

Ran BLT interleaved and de-interleaved
No problems. Tried to run core 1 sense
amplifier margins. Found no margins to
which the operation of BLT was sensitive.
I suspect that we have never run any
meaningful sense amp. margins in core.
Turned of new AMPEX core controlers.
Ran disk diagnostic some more.
Got past places where errors occured
previously.