User manual RAMSEY QAMP40

[. . . ] 40 MTR 20 WATT QRP LINEAR AMPLIFIER KIT Ramsey Electronics Model No. QAMP40 Need a little extra boost for your QRP rig?Believe it or not, 20 watts is only about an `S' unit below a 100 watt rig!This nifty little amp will add some "punch" to any QRP transmitter. · · · · · · · · Works great with Ramsey QRP rigs or any other 1-2 watt transmitters Built-in T/R relay automatically switches between receive and transmit Runs on 12 volts DC at 2 to 4 amps; ideal for field day or battery operation Multistage low pass filter for a clean signal Operates all modes: CW, SSB, or AM Fast, easy, and fun 2 hour assembly Informative manual answers questions on theory, hook-ups, and uses - enhances resale value too! [. . . ] Install L1, a 19 turn toroid inductor wound previously. If desired, a small dab of hot melt glue, bathtub sealer, or caulk may be used to secure the toroids. Install L2, the 22 turn toroid inductor - you marked it, remember?Install L3, the remaining 19 turn toroid inductor. This completes the assembly of your QRP power amplifier. Now's a good time to give your masterpiece a good going over, being especially alert for any: · bridged-over solder joints; · misplaced components; · transistors or diodes placed wrong; · electrolytic capacitors installed wrong. INITIAL TESTS: To prepare your amplifier for testing you'll need the following: · 1. Multimeter capable of measuring voltage and current. 12 volt DC power source of at least 3 amp capacity. Suitable dummy load and resonant antenna. QRP transmitter with a power output in the ½ to 2 watt range, such as the Ramsey QRP-40. Proper cables to interface between the QRP transmitter and the QRP power amplifier. With the above all set up and handy, let's get testing!Connect a multimeter to TP1 ; set the meter to read up to 5 volts DC. QAMP-40 · 12 3. Connect a dummy load to J1, the amplifier RF output. In a pinch, a light bulb may be used - see the section, "Verifying RF Power Output. " 4. Temporarily install a jumper from the collector of Q3 to ground. Apply power to the amplifier but do not turn on the transmitter. Measure the current drawn by the amplifier and slowly rotate the bias pot, R4, clockwise until you reach a reading of ¼ amp. Do not allow the current to rise above ½ amp. If you cannot adjust or reduce the current, disconnect the power supply and consult the troubleshooting hints section. The voltage at TP1 should be about 3. 2 to 3. 5 volts. [. . . ] If you're missing five 10K ohm resistors and received five extra 1K resistors, you can pretty much be assured that the '1K ohm' resistors are actually the 'missing' 10 K parts ("Hum-m-m, I guess the 'red' band really does look orange!") Ramsey Electronics project kits are packed with pride in the USA. If you believe we packed an incorrect part or omitted a part clearly indicated in your assembly manual as supplied with the basic kit by Ramsey, please write or call us with information on the part you need and proof of kit purchase. FACTORY REPAIR OF ASSEMBLED KITS: To qualify for Ramsey Electronics factory repair, kits MUST: 1. NOT be assembled with acid core solder or flux. [. . . ]