56 lines
2.0 KiB
Plaintext
56 lines
2.0 KiB
Plaintext
AST RESEARCH TECHNICAL BULLETIN TB-0005 4-23-84
|
||
|
||
|
||
SETTING CLOCK FREQUENCY FOR SIXPAKPLUS FASTER OR SLOWER
|
||
|
||
|
||
CAUTION: We suggest that you leave the factory configuration
|
||
alone. But, if you must, here is the pertinent
|
||
information you'll need.
|
||
|
||
How to set frequency of SixPak clock, so as to slow frequency
|
||
down or speed frequency up.
|
||
|
||
First, a few points of reference:
|
||
|
||
1. Clock chip U66 on SixPak board, pin 11 is the pin
|
||
responsible for checking frequency (see Diagram 1.0).
|
||
The notched end of the chip is the location of pin 1
|
||
(see Diagram 1.1).
|
||
|
||
2. Variable Capacitor; C86 located next to clock chip (see
|
||
Diagram 2.0). Turning this clockwise speeds up frequency
|
||
and turning counter-clockwise slows it down (see Diagram
|
||
2.1).
|
||
|
||
The recommended frequency range is 30.5171-30.5175KHZ.
|
||
Above 30.5175, or clockwise, is faster; and below
|
||
30.5171 KHZ, or counter-clockwise, is slower (see
|
||
Diagram 2.2).
|
||
|
||
3. Setting Frequency Counter: Racal-Dana 9906 or
|
||
Equivalent.
|
||
|
||
A) Time Base 104
|
||
B) Period A
|
||
C) Delay Out
|
||
D) DC
|
||
E) Start and Stop on Leading Edge
|
||
|
||
4. Checking voltage of battery pin 24 of clock chip and
|
||
minus side of battery holder (see Diagram 3.0).
|
||
Minimum voltage at pin 24 should be no lower than 2.3
|
||
volts, and the battery itself should be 3.0 volts; 2.8
|
||
at the lowest.
|
||
|
||
NOTE: As a portion of the data is in pictorial form, it is not
|
||
included here. To obtain a complete copy of this technical
|
||
bulletin, contact:
|
||
|
||
AST RESEARCH, INC.
|
||
2121 Alton Avenue
|
||
Irvine, California 92714
|
||
|
||
ATTENTION: Product Support
|
||
(Technical Bulletin)
|
||
|