Ramsey Electronics QRP-80 Instruction Manual Download Page 22

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QRP-80

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Incorrect orientation of transistors

Incorrect installation of diodes

Incorrect selection of inductors

Incorrect selection of frequency-dependent capacitors

Summary of Contents for QRP-80

Page 1: ... 5 KHz of tuning about the crystal frequency Front panel switching of TWO channels and includes a crystal for 3 579 MHz the International QRP frequency Excellent and clean keying waveform Built in antenna T R switch Operates on 12 15 volts DC at 1 4 amp current Appoximately 1 Watt RF power Clear concise step by step instructions carefully guide you to a finished kit that not only works but you ll ...

Page 2: ...eries HF CW Transmitters CW 700 Micro Memory CW Keyer PA Series VHF and UHF Power Amplifiers Packet Computer Interfaces QRP Power Amplifiers RAMSEY MINI KITS Many other kits are available for hobby school Scouts and just plain FUN New kits are always under development Write or call for our free Ramsey catalog 80 METER CW TRANSMITTER KIT INSTRUCTION MANUAL Ramsey Electronics publication No QRP 80 R...

Page 3: ...ematic Diagram 10 Parts layout diagram 11 Assembly instructions 12 Crystal oscillator testing 16 Initial tests 17 Verifying RF power 18 Maximizing RF power output 19 Options for finishing project 20 Enclosure ideas 20 Choosing crystals 20 Troubleshooting guide 21 Ramsey kit warranty 22 KIT ASSEMBLY AND INSTRUCTION MANUAL FOR RAMSEY ELECTRONICS INC 793 Canning Parkway Victor New York 14564 Phone 71...

Page 4: ...ower amplifier or switching from 25 to 5 watts on your new Radio Shack 10 meter rig or turning back the carrier level control on most modern transceivers For equipment description and contest competition purposes QRP refers to transmitter powers under 5 watts In our manuals for the Ramsey Amateur Band receivers for the 80 and 40 meter bands which tend to be of interest to many beginners because of...

Page 5: ...r 2 Power needs to be increased four times or 400 to result in a true 1 S unit or 6db RST gain 3 Reducing output power down to 25 of previous power should result in an S Meter or RST drop of only one 6 db unit 4 A 10 decibel increase in signal strength requires a power increase of ten times Next there are three practical facts to remember 1 The R S T system was designed originally for the human ea...

Page 6: ...QRP 80 6 that will become obvious ...

Page 7: ...ularly at 10 or 14 MHz and on up the above correlation of signal reports to power output becomes realistic S9 20 is what amplifier users expect to give and receive to justify their investment and power consumption Most commercial transceivers have typical output in the 60 200 watt range and S8 9 reports are taken for granted Actually 15 25 watts is a far more practical operating power than most am...

Page 8: ...er communication In fact the most avid QRP enthusiasts would not regard communication with a Ramsey transmitter especially challenging since they prefer the new world of milliwatt operation known as QRPp And yes the ones who have conquered the milliwatt world ARE setting records with milliwatt tests With the world record set in 1970 between Alaska and Oregon on ONE microwatt think about it this wa...

Page 9: ...STORS 3 100 ohms brown black brown R7 R9 R11 1 270 ohms red violet brown R10 1 470 ohms yellow violet brown R6 2 1K ohms brown black red R12 13 4 10K ohms brown black orange R4 5 14 15 1 47K ohms yellow violet orange R8 2 1 megohm brown black green R2 3 1 10K potentiometer R1 SEMICONDUCTORS 1 2N3904 NPN transistor Q1 2 2N3053 NPN transistor Q2 Q3 1 2N3906 PNP transistor Q4 may also be 221 334 or I...

Page 10: ...line to Q1 and the T R circuitry of D1 and D2 S1 selects either of two crystals R1 D3 D4 and L1 form a varactor controlled series resonant circuit with the crystal Adjusting R1 permits a crystal frequency swing of up to 7 KHz about the crystal frequency Q3 is a Class C RF amplifier that amplifies the RF output of Q2 to the final RF power output level L6 C17 and C18 form a low pass filter Butterwor...

Page 11: ...QRP 80 11 BLOCK DIAGRAM ...

Page 12: ...nsmitter has also developed some familiarity with general electronics practices and language Therefore you can expect the following procedures to move along with less of the hand holding which we offer for our receivers and other kit projects in which the FCC has less interest FIRST ASSEMBLY STEPS To get started and to put some landmarks on the circuit board we ll insert and install the 3 RCA phon...

Page 13: ...transmission and permits the antenna to be connected to the receiver jack during key up conditions To further complete this section of the circuit we now install the first of three 100 uh RF chokes They look like resistors with brown black brown silver or gold bands In the following steps be sure to save the clipped off component lead wires from R12 and R13 These will be used for jumpers in later ...

Page 14: ...QRP 80 14 QRP 80 SCHEMATIC DIAGRAM ...

Page 15: ...omplete with one crystal in the CW range usually the suggested QRP international calling frequency S1 permits your choice of any two installed crystals the one that comes with your kit and another which you may add on your own If you plan to add a socket for your own crystal it should be wired to the A crystal position The PC board used in your kit is common to all the QRP transmitters in the Rams...

Page 16: ...rystal connection so that you can install virtually any standard crystal case style HALFTIME SUGGESTION It won t be too much longer before your Ramsey transmitter is ready for testing and on the air operation It is common for experimental projects to give disappointing results because of inefficient haywire hookups as soon as they are completed This is most especially true with low power transmitt...

Page 17: ...r is now completed If you somehow skipped or improvised on our halftime instructions NOW is the time to make proper preparations for testing and using your transmitter As we suggest in all Ramsey Electronics kit projects now might also be an excellent time to take a break and then come back to re check your connections or have a friend go over them Give extra attention to the work associated with ...

Page 18: ...some help but even the simplest crystal oscillator can send a fine signal into your neighbor s receiver as we have already discussed Ideally you have an small RF wattmeter already inserted in the antenna line capable of accurately measuring low output power in watts and even milliwatts And it cost you less than what you paid for the transmitter kit Right If not we have a few other ideas for you OK...

Page 19: ...vide a variety of circuits for RF wattmeters and relative field strength indicators including methods of using your VOM as an indicating device CQ magazine for March 1990 offers an article by KB4ZGC on how to make a highly accurate yet inexpensive dummy load and wattmeter capable of showing 1 10 watt differences in RF power MAXIMIZING RF POWER OUTPUT Hopefully the introductory discussion about the...

Page 20: ...a variety of enclosures of your own design and choosing You might be planning to combine several Ramsey circuit kit boards in a single enclosure Use of the inexpensive and attractive Ramsey case and knob set will give your unit that nice finished look and increase its resale value These sturdy black instrument cases are supplied with printed overlays on front and rear panels knobs rubber feet and ...

Page 21: ...cluding DX were made with this Ramsey transmitter using both a mobile whip antenna and simple dipole on the balcony of a condo building If you elect to use an antenna tuner it is extremely important that you understand exactly how to use tuners and what they can and cannot do A watt of RF can easily become lost in an incorrectly adjusted antenna matching device The whole idea of this transmitter i...

Page 22: ...QRP 80 22 Incorrect orientation of transistors Incorrect installation of diodes Incorrect selection of inductors Incorrect selection of frequency dependent capacitors ...

Page 23: ...ch 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 ...

Page 24: ...ication No QRP 80 Assembly and Instruction manual for RAMSEY MODEL NO QRP 80 RAMSEY ELECTRONICS INC 793 Canning Parkway Victor New York 14564 Phone 716 924 4560 Fax 716 924 4555 Printed on recycled REQUIRED TOOLS Soldering Iron Radio Shack RS64 2072 Thin Rosin Core Solder RS64 025 Needle Nose Pliers RS64 1844 Small Diagonal Cutters RS64 1845 OR Complete Soldering Tool Set RS64 2801 ADDITIONAL SUGG...

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