Ramsey Electronics LPA1, Инструкция по эксплуатации

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LPA1
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22. Install C9, .01uF capacitor [marked .01 or 103 or 10nF]. The
insulation should be stripped from the legs and a topside connection
made nearest the edge of the board.
Now that you have installed the biasing circuit, we have only a few more
parts to put in before we install the amplifiers. This is a good time to look
back over your work and look for misplaced parts and bad solder joints. You
should take a rest now if you need one.
Take a look at the table on page 10. This table shows the gain of your Power
Booster Amplifier at certain frequencies. The higher the gain, the more
power your kit will put out with the same input signal. Using the table to aid
you, decide whether or not you would like to insert the feedback circuit (R8
and C5). As a default, you should install R8 and C5.
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23. If you have decided to include the feedback circuit, install R8 now.
R8 is a 220 ohm resistor [red-red-brown].
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24. Install C5 only if you have decided to include the feedback circuit.
C5 is a .01uF capacitor [marked .01 or 103]. Be sure to take the
insulation off of the legs first.
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25. Install C7, .01 uF capacitor [marked .01 or 103 or 10nF]. Strip the
insulation off of the legs before installing.
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26. Install C8, .01 uF capacitor [marked .01 or 103 or 10nF]. Strip the
insulation off of the legs.
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27. Install C6, .01uF capacitor [marked .01 or 103 or 10nF]. Do you
really need to strip the insulation off of the legs? YES!
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28. Identify Q2, an MRF581 NPN Power Transistor. This part is round,
has four legs coming off of it and is marked “581”. You may notice that
there are two parts matching this description. Q2 is the larger of the two
parts, and the other, the MAR3 Amplifier, is smaller and has a “3” printed
on it.
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29. Turn over the board, so that the soldered side is up. You should see
a small “M” near one lead of the transistor. This “M” should be near the
lead closest to L1. If there are two “M” s on the part, orient the part using
the Motorola trademark “M”. Taking the two leads on either side of the
lead nearest the Motorola “M,” insert them through the two holes in the
board. These two leads both go to ground. Check to see that the “M” is
still closest to L1. Solder the two leads on the top and bottom sides of
the
board.
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30. With the two remaining leads flat against the underside of the board,