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Connect an antenna to the top of resistor R66. Band noise and maybe a station can be heard.
Adjust LO trim capacitor TC9 until the received band noise sounds the loudest and is at
approximately 1 KHz. This isn't a critical adjustment at this time, just use your ears and let
them be your guide. The receiver is listening to signals in the band and at the image frequency,
so you may hear CW and shortwave broadcast signals together.
Your Measurements/Observations - ______________________________________________
____________________________________________________________________________
Receive RF Amplifier
[ ]
The Receive RF Amplifier stage is not used on 40-meters. Instead, a jumper is connected
between the upper pad for capacitor C86 and transformer pad T6-5. 40-Meter builders can
proceed directly to the "Receive Input Band Pass Filter" section.
[ ]
Wind and install transformer T6. The finished transformer should look like the next figure
with a 3-turn winding, a tap, and then followed with a 5-turn winding.
The 1-turn emitter winding is added after the transformer is soldered on to the PCB. On 30-
meters, this transformer has a 2-turn winding, a tap, and a 1-turn winding.
[ ]
Install inductor L14.
[ ]
Install transistor Q17.
[ ]
Install diodes D12 and D23. Note cathode ends (bar) so they are installed correctly.
[ ]
Install resistors R67, R68, and R72.
[ ]
Install capacitors C86, C88, C89, and C90.
Your PCB should look like that shown in the next figure.
- Figure 29 -
25
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