FR-10
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27. Install C12, 47 pf.
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28. Install varactor diode D1.It looks like a transistor with just two
leads. The flat side faces L3 so be sure to orient it correctly.
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29. Install R8, 47K ohms [yellow-violet-orange].
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30. Install R9, 270 ohms [red-violet-brown].
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31. Install C13, .01 uf [marked .01 or 103 or 10nf].
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32. Installation of C14. This is the first of 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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33. Install C14, 100 to 220 uf, observing correct polarity.
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34. Install C15, 4.7 or 10 uf, observing correct polarity.
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35. Install jumper JMP1.
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36. Install jumper JMP3.
PROGRESS SUMMARY
So far, you have wired the tuned input from the antenna, the RF
preamplifier, and the NE602 mixer-oscillator, including the varactor
tuning circuit. The work you have done so far 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.
FR-10
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15. Install R5, 470 ohms [yellow-violet-brown].
2. NE602 OSCILLATOR-MIXER and VARACTOR TUNING
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16. Install R6, 270 ohms. [red-violet-brown]
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17. Install C7, a .001 uF bypass capacitor [marked .001,102, or
1 nF].
In installing the NE602 IC, you may wish to use an 8-pin DIP socket
rather than soldering the IC directly to the board. Reasons for doing this
might include the peace of mind of beginners afraid of damaging the IC,
or experienced builders testing the merits of the NE602's cousin, the
SE602. However, please be aware that we have seen more service
problems with improper socket insertion than from soldering heat
damage to IC's. Even if this is your first IC, don't be afraid to use enough
heat to make 8 clean connections, but DO be sure to correctly orient the
end marked by a band, dot, or notch. Before soldering, make sure that
the IC or socket is perfectly flat against the top of the PC board.
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18. Install U1, the NE602 in accord with the preceding directions.
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19. Install the FL1 ceramic filter. This component is a brown, molded
"blob" with 3 leads and may be installed either way.
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20. Install jumper wire JMP4. Use a scrap component lead wire bent
into a small loop that connects the two PC board holes. Jumpers
act as "bridges" over PC board traces underneath.
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21. Install C8, .001 uf [marked .001 or 102].
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22. Install C10, 100 pf [marked 100 or 101].
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23. Install R7, 10K [brown-black-orange].
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24. Install C9, 100 pf [marked 100 or 101].
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25. Install C11, .01 uf [marked .01 or 103 or 10 nf].
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26. Install L3. It is important that the body of this coil be snug
against the PC board for mechanical stability, which directly
affects the frequency stability of the receiver. Make good, solid
solder connections!
Содержание FR-10
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