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sure all 8 pins are through the board before soldering the IC in place.
This IC is responsible for the master clock oscillator for the direction
finder unit , and replaces a few dozen discreet components.
5. Install C24, .001uF disc capacitor (marked 102).
6. Install R29, 68K ohm (blue-gray-orange).
7. Install R28, 18K ohm (brown-gray-orange).
8. Install C26, .001uF disc capacitor (marked 102).
9. Install R27, 10K ohm (brown-black-orange).
10. Install R26, 33K ohm (orange-orange-orange).
11. Identify C25, the 1 uF electrolytic capacitor. Electrolytic capacitors
are polarized with a (+) and (-) lead and must be installed in the correct
orientation. Ordinarily, only the negative side is marked on the capacitor
body with a dark band and the (-) sign clearly shown, while the PC
boards will usually show the (+) hole location. Use care to ensure proper
polarity. See the parts diagram for proper placement. The capacitor
should fit snugly down to the PC board.
Now it's time to build the power supply regulation portion of the circuit. We
need a well regulated low noise power supply to enable our circuit to work at
peak performance.
12. Identify VR1, the 7805 voltage regulator IC. Install as shown in the
diagram by carefully pre-bending the component leads at right angles to
the regulator IC. The component should fit flush to the printed circuit
board. Solder all three leads.
13. Install electrolytic capacitor C29, 100 uF. Again, this is an electrolytic
capacitor and must be mounted with respect to the correct polarity.
14. In the same manner, install C32, 1 uF electrolytic. Watch that polar-
ity!
15. Install C31, .1uF disc capacitor (marked 104).
16. Install R42, 47 ohm (yellow-violet-black).
17. Install C30, 100 uF electrolytic. Be sure to orient the polarity as
shown in the diagram.
18. Identify D6, the 1N4002 diode (epoxy case with a polarity "band" de-
DDF1 • 15
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