Service manual

DOUBLE-DENSITY DISK CONTROLLER ----l15 .. 1
Service
RECALIBRATION
You will need the following equipment to calibrate your Disk Controller Board:
• A Digital Voltmeter
(DVM) with 3-1/2 digit readout.
• A calibrated oscilloscope
with sweep speeds of 100 ns/cm and 200 ns/cm, and
an operating scale of 5 V peak-to-peak.
• A
Frequency Counter capable of measuring 2.00 MHz. (Optional, but
preferred).
• HDOS 2.0 modified
with INIT or CP/M 2.2.03 with FORMAT software.
If you cannot obtain the proper results in the following steps, refer to the "In Case of
Difficulty" section of
this manual and correct any difficulties before proceeding.
Refer
to Figure 5-1 (Page 5-3) when you perform the "Recalibration."