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previously installed components. The center of the BNC is wired to the "ANT" pad and the
BNC ground to the "GND" pad.
Your PCB should look like that shown in the next figure.
- Figure 44 -
Test – Attach a TO-220 style heat sink (or fabricate something similar) to final transistor Q25 as
shown in the next figure.
- Figure 45 -
Connect a speaker or headphones to the "SPKR" jack. Connect a 50 Ohm dummy load/watt
meter to the output BNC connector. Connect an RF probe or oscilloscope to the "ANT" side of
the BNC connector and the ground of the probe or scope to the "GND" side of the BNC
connector. Adjust trim resistor R87 fully counter clockwise. Apply power to the PCB. Jumper
the "Key" pads together to key the transmitter. Do not keep the transmitter keyed for more
than 30 seconds at a time while performing these tests, to prevent the final transistor from
overheating. Begin turning R87 in a clockwise direction while alternately adjusting trim
37
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