Star Tech Journal

__ 4 ____ ST4R*7ECHJOf.lRl'~•••---------------------A-u_a_u_sT_1s_s_4 __
NEWS BITS
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EIA BETS NEW STANDARDS
FDR SILICON DIGITAL ICe
T
he Engineering Department of the
Electronic Industries Association has
established JEDEC Standard No. 7, setting
industry specifications for three series of new
high-speed silicon-gate digital ICs.
The 54/74HC series includes buffered
CMOS logic devices with the primary charac-
teristic of V 1L (logical low-input voltage) and
V 1H (logical high input voltage) ratings for
good noise immunity in CMOS system designs.
The 54/74HCU series includes a limited
number of unbuffered (1 active logic circuit)
inverters or gates where V 1L and V 1H ratings
are less than those of the HC series. The third
series is designated 54/74HCT, having V 1L
and V 1H ratingsof0.8- and 2-volts respectively
for direct interfacing with TTL logic ICs.
STERN
BAG MAN TO SUPER BAGMAN WAVEV VIDEO MOD
Y
our Bagman to Super Bagman con-
version might experience a wavey or
curvey picture on the left side of the screen.
Solution: Change resistor R78 on the main
logic board from 4.7K ohms to 1 K
ohms per diagram.
/CHANGE TO 1 K .n..
+sv/ __
R78
4.7K
0GND
17
SYNC
U
BLUE
16
GREEN
T
RED