Ramsey Electronics AM1, Assembly And Instruction Manual

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AM1
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5. Solder all connections unless directed otherwise. Use enough
heat and solder flow for clean, shiny, completed connections.
6. Trim or nip all excess wires extending beyond each solder
connection, taking care that wire trimmings do not become lodged in
PC-board solder connections.
Now, let's get building!
Since you may appreciate some “warm-up” soldering practice as well as a
chance to put some “landmarks” on the PC board, we’ll first install some
“hardware” components. This will also help us to get acquainted with the up -
down, left - right orientation of the circuit board. Remember that the
components will be mounted on the “component” (printed) side of the circuit
board and then soldered on the “solder” (foil) side of the circuit board.
ˆ 1. Install DPDT switch S1. Position it so that the plunger of the switch
extends over the edge of the PC board. Be sure to push the switch flat
to the circuit board. Solder all six connections.
ˆ
2. Install RCA phono jacks J1 and J2. These connectors will “snap” into
place before soldering. Don’t be afraid to completely solder all three
ground connections as these will also limit the “stress” on the input and
antenna connections.
ˆ 3. Install the 2.5 mm power connector in the J3 position.
We’ll now begin to construct the RF oscillator section of the AM1. Be sure to
mount the components as close as possible to the PC board to avoid
“radiating” any unwanted signals due to long lead lengths.
ˆ 4. Install L2, the slug tuned inductor. Solder all three tabs.
ˆ 5. Install C8, .01 µF disc capacitor [marked .01 or 103 or 10nF].
ˆ 6. Install R8, 10K ohm [brown-black-orange].
ˆ 7. Install C6, .01 µF disc capacitor [marked .01 or 103 or 10nF].
ˆ
8. Identify Q6, a 2N3904 NPN transistor. When installing Q6, observe
correct placement of the flat side. Press the transistor snugly into the PC
board so that only a minimum amount of wire lead is exposed above the
board. In soldering, do not be afraid of using enough heat to make a
good solid connection.
ˆ 9. Install R11, 270 ohm [red-violet-brown].
ˆ
10. Install R7, another 270 ohm [red-violet-brown].