Ramsey Electronics FR220, Инструкция по эксплуатации

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FR-220
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29. Install varactor diode D1, it has a small black body with white
and green bands. The white banded end signifies the cathode side.
It is important that you have correctly identified D1 as type BB405
and have not confused it with the common signal diode D2.
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30. Install R8, 47K ohms [yellow-violet-orange].
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31. Install R9, 270 ohms [red-violet-brown].
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32. Install C13, .01 uf (marked .01 or 103 or 10nf).
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33. Installation of C14. This is the first the electrolytic or "polarized"
capacitors that you will install. This means these capacitors have a
positive (+) and negative (-) side and therefore a right way and
wrong way of installation. Ordinarily, only the negative side is
marked on the capacitor body, a dark band with the (-) sign clearly
shown. The value of C14 is not critical and may be any value from
100 to 220 uf.
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34. Install C14, 100 to 220 uf, observing correct polarity.
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35. Install C15, 4.7 or 10 uf, observing correct polarity.
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36. Install jumper JMP1.
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37. Install jumper JMP3.
PROGRESS SUMMARY
So far, you have wired the tuned input from the antenna, the RF
preamplifier, and the SA602 mixer-oscillator, including the varactor
tuning circuit. The work you have done has actually formed a simple
receiver capable of tuning in VHF signals of all kinds and converting
them to a low-level 10.7 MHz output to be amplified by Q2. This is a
good time to review the steps completed so far before proceeding. Due
to the many functions of the MC3359 FM receiver IC, further assembly
steps will be in the order of easiest parts installation.