BLOCK ERROR RATE is always available. The VU meters are converted into Error Rate Meters

SHIFT then MENU
Continue to press MENU untill "bEr off"
Press UP arrow or DOWN Arrow to change display to "bEr on".
Press SHIFT.
Press Play.
The meters are configured as follows:

1 Tape Edge (head A)
2 Tape Edge (head B)\
3 (Not Used)
4 (Not Used)
5 Center of the tape (head A)
6 Center of the tape (head B)
7 (Not Used)
8 (Not Used)

Error Quality (number of block error among 128 blocks)
Number of lit segements Number of Error Blocks
0 0-7
1 8-15
2 16-23
3 24-31
4 32-39
5 40-47
6 48-55
7 56-63
8 64-71
9 72-79
10 80-87
11 88-95
12 96-128
Change "on" to "off" to disable the Error Rate Meter

The Service Manual has a sequence of Test mode error detection. This information is not secret but is of no use to anyone without factory service training. MEP