The Easy

Album contains three 12 LP's Th hr. Instruction

• No Visual Gimmicks To Distract You

• Just Listen And Learn

Based on modern psychological techniques—This course will take you beyond 13 in

LESS THAN HALF THE TIME! Available on magnetic tape $9.95 - Cassette, S10.95

epsilon 00 records

508 East Washington St., Areola, Illinois 61910

the delay so that there is a 1,27 fis between the leading edges of the two signals. Again, without a dual-trace oscilloscope, mix the finverted nondelayed output with the normal delayed output. The pulse on the oscilloscope from the output of your mixing gate has a width equal to the delay time.

Since the outputs of this unit are the outputs of gates, they will not drive a low impedance load. All inputs to other equipment should be high impedance and the line should not be terminated with a resistor. This situation is ideal in my station as most equipment is of IC contruction and the output of the sync generator simply drives other gates, if you absolutely require low impedance signals, the outputs of the gates may be buffered with simple emitter followers.

Wire the monostables and their inverters next. Look at the output of the inverters and adjust the pulse widths to the correct values. Remember the pulses are negative going at the outputs of the inverters. Wire gate 3 first, then gate 1, and finally gate 2. The outputs of the three gates may be compared with the scope pictures in Fig. 7. Their widths should be: gate 1,571.5 jus; gate 2, 190,5 ^s;gate 3, 2857.5 jus. Lastly, wire the output gating and connect it all together. Sync, blanking, and drive should now appear at their respective output terminals. Check the appearance of the blanking and drive with an oscilloscope. The sync waveform may only be viewed reliably using an oscilloscope with delaying sweep. The delay has to be longer than two fields, as the horizontal sync pulses alternate their position every other field. Without these precautions you can not be certain that your scope trace is an accurate indication of the output waveform. Note, however, that no adjustments have to be made while looking at this waveform so if you trust your wiring and previous adjustment procedure, you can be confident of having a correct sync signal. If you still insist on seeing the sync waveform, it is possible lo add a single flip-flop as a 2:1 counter connected to the output of this 2:1 divider to the external sync on your scope and you should be able, after some adjustment, to see the sync signal, . . . K9AÀC/7 ■

0 0

Post a comment