Ramsey Electronics FZ-146 Specifications download pdf (Page 91)

FX-146 • 91

Install the following resistors, each in upright position:

 DR13: R16, 47K ohm (yellow-violet-orange).

 DR14: R17, 470 ohm (yellow-violet-brown).

 DR15: R12, 100 ohm (brown-black-brown).

 DR16. Install C20, 100 pf. (marked 100 or 101).

 DR17. Install C30, 47 pf (marked 47).

 DR18. Install L5, .015 uH, a small 2 turn wire coil.

 DR19. Install C28, 47 pf (marked 47).

 DR20. Install L2, another .015 uH small 2 turn wire coil.

 DR21. Install L6, yet another 2 turn .015 uH coil.

 DR22. Install C31, 47 pf (marked 47).

 DR23. Install C104, 8.2 pf.

INTERMISSION: Notice how our work is methodically creeping toward all

the FM IC circuitry you did in Stage CR ?

 DR24. Install C22, 100 pf (marked 100 or 101).

 DR25. Install R14, 47K ohm (yellow-violet-orange).

 DR26. Install R10, 470 ohm (yellow-violet-brown).

 DR27a. 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.

 DR27b. Install Q2, 2SC2498 transistor.

 DR28. 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 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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Ramsey Electronics FZ-146 Specifications Page 91