Ramsey Electronics AM25, Сборка и инструкция по эксплуатации

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AM25
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ˆ 21. Install R33, 10 ohm [brown-black-black].
ˆ 22. Install R34, another 10 ohm [brown-black-black].
ˆ 23. Install C26, .1 µF disc capacitor [marked .1 or 104].
ˆ 24. Locate a 1/2 inch long piece of scrap component lead. Install it into
the black hole near trimmer capacitor C16. Leave about 1/2” standing up
from the PC board, this wire point, which we will call TP1, will provide a
convenient point for you to connect a meter probe.
You have just completed most of the RF carrier oscillator. Take a moment
now to recheck you work for clean, shiny solder connections. Resolder any
connections that are less than perfect.
We’ll get back to building now, starting with the PLL circuitry.
ˆ 25. Install U2, MC145106 PLL IC chip. Pay close attention to the
notched end of the IC package, it must be oriented exactly as shown on
the PC board or else! Ensure that all pins fit fully through the PC board
and are securely soldered.
ˆ 26. Install R30, 10K ohm [brown-black-orange].
ˆ 27. Install R32, 470 ohm [yellow-violet-brown].
ˆ 28. Install Q10, 2N3904 transistor. Be sure to orient it correctly! See the
parts diagram for correct orientation.
ˆ 29. Install Q2, another 2N3904 transistor, watch that flat side.
ˆ 30. Install Q1, yet another 2N3904 transistor. The 2N3904 is one of the
most common NPN silicon transistors ever made, in fact, one factory that
I visited in Korea manufactured over 50 million of them per month!
ˆ 31. Install R1, 10K ohm [brown-black-orange].
ˆ 32. Install C11, a 10 µF electrolytic capacitor, watch that polarity!
ˆ 33. Install C10, .01 µF disc capacitor [marked .01 or 103 or 10nF].
ˆ 34. Install C8, another .01 µF disc capacitor.
ˆ 35. Install C9, 10 µF electrolytic capacitor, observe polarity.
ˆ 36. Install jumper wire, JMP4.
The last few parts formed a simple regulated power supply for the RF
oscillator. A neat trick is the use of a reversed biased transistor as a zener
diode - take a look at Q2, see how its base and collector are shorted
together. Q2 makes a neat 6 - 7 volt zener!
ˆ 37. Install C30, 10 µF electrolytic capacitor, watch polarity.
ˆ 38. Install JMP1 using a scrap piece of component lead wire.
ˆ 39. Install R24, 1Meg ohm [brown-black-green].
ˆ 40. Install R25, 10K ohm resistor [brown-black-orange].