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DR12c. After making sure that the body of Q3 is snugly against the PC
board and correctly oriented as shown above, solder and trim all three
wires. That's all there is to it!
DR13: Install C20, 8.2 pf. (marked 8.2).
DR14: Install C30, 22 pf (marked 22).
DR15. Install L5, .015 uH, a small 2 turn wire coil.
DR16. Install C28, 3.9 pf (marked 3.9).
DR17. Install L6, another 2 turn .015 uH coil.
DR18. Install C31, 22 pf (marked 22).
INTERMISSION: Notice how our work is methodically creeping toward all the
FM IC circuitry you did in Stage CR ?
DR19. Install C22, 8.2 pf (marked 8.2).
DR20. Install R14, 47K ohm (yellow-violet-orange).
DR21. Install R10, 470 ohm (yellow-violet-brown).
DR22. Select a 2SC2498 NPN RF transistor. This is the first of such
transistors used in this circuit, they are marked with 'C2498' on the flat
side. Again, do not confuse these with the more common 2N3904 (or
similar) transistors such as already installed.
DR23. Install Q2, 2SC2498 transistor.
DR24. Install C17, 100 pf (marked 100 or 101), and all your work in this
stage is now connected to the RF input of U1.
Stage DR Progress Note:
No other testing is required at this point other than to double-check the
accuracy of your parts installations. However, experienced builders will
recognize that VHF signals could now be received very well by connecting an
antenna and tuning a signal generator coupled to pin 2 of U1, provided that
the T-R circuitry is operational. A more useful preliminary receiver test will be
conducted after we complete the VCO stage.
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