MFJ-8100K Manual

Note: The L5 inductor for Band E is a wind-it-yourself "toroidal coil" (don't worry: it's
easy!) which we'll make and install in Phase 5 so that it is not subjected to
bumping and bending during other assembly.
1-6. Install R4, 10K (brown-black-orange). Its position is between L1 and L2.
1-7. Install C4, .1µF (body marking: 104Z), near L1.
1-8. Install R13, 2.2K (red-red-red). (This is a current limiting resistor for the LED
power indicator.)
1-9. Install C3, 47pf (body marking: 47 or 470).
1-10. Install C5, the miniature trimmer capacitor, making sure the to orient its body
shape just like the circuit board outline. Before soldering , adjust the tuning
screw so that its slot is pointed just like the outline on the board.
We've accomplished something important; we got started, and we've made sure that this
receiver will tune correctly.
Construction Phase 2 (Steps 2-1 through 2-20)
The parts in Phase 2 are the heart of your receiver; working together with the tuning
circuit begun in Phase 1. Building this section is simply a matter of identifying and
installing the parts correctly. This phase includes all three FET transistors and one
electrolytic capacitor, all of which are to be installed in one correct way only. You really
can't go wrong; simply position the transistors and electrolytic capacitors exactly as
illustrated, right on the board.
2-1. Install R5, 10K (brown-black-orange).
2-2. Install C7, .01µF (body marking 103M).
2-3. Install C18, 1µF electrolytic. Notice that the negative (-) side is clearly
marked on the capacitor, and that the (+) position is marked on the PC board.
2-4. Install R3, 10K (brown-black-orange).
2-5. Install R6, 1K (brown-black-red).
2-6. Install R17, 10 ohm (brown-black-black).
2-7. Install C6, 33pF (body marking 33K).
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