Ramsey Electronics FZ-146 Specifications download pdf (Page 85)

FX-146 • 85

 CR29. Install FL1, the 21.4 MHz IF filter. Its 3 wires may be inserted

either way; make sure its body is snug against the top of the board

before soldering.

 CR30. Prepare three 8" lengths of hookup wire for connecting R13, the

100K Squelch Control. Strip back ¼" from one end of each wire. Tin all

ends.

• Select a wire, connect one stripped end to the three connecting

lugs of the control.

• Observe the diagram and locate the squelch wire connections on

the printed circuit board.

• Connect the three wires to the printed circuit board as shown in the

diagram. Pay careful attention to the wire placement as not to wire

the

squelch pot in

“backwards”.

 CR31 Install D20, 6.2 volt zener diode (gray body, black band).

Observe correct placement of the banded cathode end. Zener diodes

are widely used as voltage regulators. They have the interesting

property of keeping a constant voltage across their terminal leads.

 CR32 Install Q17, 2N3904 transistor, observe the flat side.

The last 4 steps involved the building of a voltage regulator to supply a

steady source of voltage to the receiver IC chip. At this point in your work,

you could actually receive strong local signals by connecting an antenna

wire at C17 and a high frequency signal source (e.g. a signal generator) to

the input of U1 at pin 1. The signal you would receive would be on a

FX PCBOARD

FL1

C16

SQUELCH

1 2 ... 80 81 82 83 84 85 86 87 88 89 90 ... 144 145

No comments

Ramsey Electronics FZ-146 Specifications Page 85