Ramsey Electronics QAMP40 manual ˆ3. Install J3, PC mount DC power jack

Models: QAMP40

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Insert the part, oriented correctly, into its correct holes in the PC board. If helpful, gently bend the part’s wire leads or tabs to hold it in place, with the body of the part snugly against the top side (component side) of the PC board.

Solder all wires or pins of the part, whether the 2 wires of a resistor or the 3 or 4 wires of a transistor.

Trim all excess wires extending beyond each solder connection, taking care that wire trimmings do not become lodged in PC board solder connections.

ˆ1. Install S1, PC mount pushbutton switch. Solder all 6 pins securely.

ˆ2. Install J1 and J2, PC mount RCA phono jacks. Solder all 4 pins on each

securely as these connectors will be subjected to some stress when coax cables are connected to them.

ˆ3. Install J3, PC mount DC power jack.

ˆ4. Install relay K1. Notice that it installs only one way.

ˆ5. Install potentiometer R4. This pot allows adjustment of the bias to the power transistors.

ˆ6. Install C9, .01 µf disc capacitor (marked .01 or 103 or 10 nf).

ˆ7. Install Q5, 221334 PNP transistor, oriented with the flat side toward D2.

ˆ8. Install R6, 470 ohm resistor (yellow-violet-brown).

ˆ9. Install R10, 51 ohm resistor (green-brown-black).

ˆ10. Install R11, 2.2 K ohm resistor (red-red-red).

ˆ11. Install R12, 10 K ohm resistor (brown-black-orange).

ˆ12. Install D2 and D3, 1N4148 style signal diodes (glass body with black band). Pay special attention to the banded endS. The banded end on a diode is the cathode and must be oriented correctly or the circuit will not work. Both diode D3 and diode D2 are detectors for sensing applied RF power.

ˆ13. Install C10, .1 µf disc capacitor (marked .1 or 104).

ˆ14. Install R7, 100 K ohm resistor (brown-black-yellow).

ˆ15. Install Q3 and Q4, 2N3904 NPN transistors, observing proper orientation of the flat side. These two transistors amplify the signal diode's output to a level high enough to close relay K1.

QAMP-40 • 7

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Ramsey Electronics QAMP40 manual ˆ3. Install J3, PC mount DC power jack