Ramsey Electronics FZ-146 Specifications download pdf (Page 124)

FX 146 • 124

 M18. Install Q11, NPN transistor type 2N3904. Be sure to orient flat side

as shown.

 M19. Identify and install R46, the yellow color modulation control

trimmer potentiometer. It differs from trimmer capacitors by having three

terminals. Simply place it in position and solder all three points.

NOTE: The remaining three transistors used in this section are PNP types,

2N3906 or similar, marked 228256. It is essential to use the correct

transistor type for Q12, Q13, Q14.

 M20. Install Q12, PNP transistor type 228256. Orient flat side as shown.

 M21. Similarly, install Q13, PNP type 228256.

 M22. Install Q14, PNP type 228256.

Install the following additional parts:

 M23: R60, near Q12, 10K (brown-black-orange).

 M24: R62, also 10K (brown-black-orange).

 M25: R111, near Q13, 4.7K (yellow-violet-red).

 M26: R40, 100K (brown-black-yellow).

 M27: R63, 470 ohms (yellow-violet-brown).

 M28: R64, also 470 ohms (yellow-violet-brown).

 M29: R112, 4.7K (yellow-violet-red).

 M30: R39, near Q11, 47K (yellow-violet-orange).

 M31: Install diode D11, 1N914/1N4148.Orient the banded end as

shown.

 M32: Similarly, install diode D12, another 1N914/1N4148.

IMPORTANT: The following parts are located in areas of the PC board that

already have been assembled. If the ham in you pursued an assembly

sequence different from these step-by-step directions, you may already have

soldered in these parts. If so, no harm is done. Be certain now, though, that

the following are installed:

 M33: R21, 470 ohms (yellow-violet-brown).

 M34a: PIN diode D2, type BA482, near R21. BA482 PIN diodes have

an orange body, with a red cathode band. (D2 grounds the receiver

input during transmit.)

 M34b: PIN diode D7, also type BA482, which passes RF to the antenna

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Ramsey Electronics FZ-146 Specifications Page 124