Global Specialties PB-500 - Manual - Manual (Page 8)

8
PB-500 CHECKOUT
1. Po wer Se ction - AC Adaptor Ope ration
a) Plug AC adapto r into Jl then in wa ll o utlet. Che ck for -12 vo lts
between " -12 v" an d "GND.
b) Check for +12 vo lts between "+12 v" a nd "GND". Vo lta ge s
should measure +/ -12 vo lts +/ -5%.
2. Variab le Supplies
a) Measure the vo lta ge between " -V" and "GND", u sin g the slide
pot (R2 ) the supply vo lta ge shou ld va ry from 0 to -7.5 vo lts +/ -
10%.
b) Measure the vo lta ge between "+V" an d "GND", u sin g the slide
potentiometer (R6 ) the supply volta ge should va ry from 0 to +7.5
vo lts +/ -10%.
3. Short Circuit Indica tors
a) Set both variable supplies to 7.5, pla ce a jumper from " -V" to
"GND" CR2 should l i g h t indicatin g a shorted condition.
b) Place a jumper fro m "+V" to "GND" CR4 should l i g h t indicating
a shorted cond ition. Remo ve jumpers the LEDs shou ld go out.
4. Function Gene rato r
NOTE: A l l waveforms shou ld be 1kh z +/ -20 % with a 50% duty cycle
Triangle W ave
a) Set S3 to "TRI" position.
b) Attach an oscilloscope between "SIN/TRI" and "GND".
c) Adjust R15 (locate d under PC boa rd) for a symmetrica l
wa veform with approximately a 9 v pk to pk.
Sine W ave
a) Set S3 to "SIN" po sition.
b) The wa ve form on you r oscillo scope should be a symmetrical
sinuso id with app roximately a 4 v pk to pk. amplitude
Square W ave
a) Mo ve oscillo scope lead from "SIN/TRI" to "SOR".
b) The wa veform on your oscilloscope sh ould be a symmetrical
squa re wa ve with a n 8v p k to pk. Amplitude.
TTL
a) Mo ve the oscillo scope lead from "SOR" to "TTL".
b) The wa veform on your oscilloscope sh ould be a pulse tra in
goin g from 0 to +5 vo lts. Disconne ct o scillo scope from unit.