background image

PA-1 

 4  

PA1 AMPLIFIER 

 
All of us at Ramsey say THANKS for your interest in building the world's 
most  popular 2 Meter amplifier project. Successful construction and 
installation of your PA1 amplifier can give your handheld 2 Meter transceiver 
an RF power boost beyond the performance of many fixed and mobile units.  
 
 BEFORE you begin building your PA1, we ask you to read the warranty 
information on page 14 and think about a few details in advance:   
 
The PA1 is a true "Ham Radio" kit project which presumes the expertise that 
goes along with your license. You need to know how to "tack solder", wind 
simple VHF coils per our directions, and how to finish your PA1 with suitable 
enclosure, connectors, T-R switching and I/O wiring.   
 
The Ramsey RFS1 RF-sensing T-R switch kit is available as an easy 
companion kit for the PA1.   
 
The Ramsey PR10 Low Noise Pre-amplifier Kit can be worked into your final 
T-R installation to boost those hard-to-copy signals.   
 
We ask you to understand that the VHF Power Transistor that is the heart 
and soul of this circuit cannot be guaranteed beyond careful tests by BOTH 
the manufacturer and our technicians. Because this expensive transistor can 
be damaged by either incorrect soldering OR incorrect physical mounting, 
there can be NO warranty on this part unless your own additional test 
BEFORE ANY soldering and mounting shows a clear defect.   
 
Use of a VHF power output wattmeter is essential to correct adjustment of 
the PA1.   
 
If you decide, before beginning any assembly of your PA1 kit, that this  
project is not quite what you're ready for, you may return the complete,  
unassembled PA1 kit to the Ramsey factory. 
 
OR, if you are ready to join the thousands of hams world-wide who enjoy the 
PA1 as the most economical possible HT improvement for the highly-popular 
2 Meter band, we will be happy to guide you through every construction step 
in the spirit of the "Learn-As-You-Build" philosophy for all Ramsey Kit 
manuals for the new millenium. 

 

 

Summary of Contents for PA1

Page 1: ...nd connectors Informative manual answers questions on theory hookup and uses enhances resale value too Maximum output of 35 40 watts max drive of 8 watts Mounts in any small aluminum case which then w...

Page 2: ...tion Detector ML Music Lights Kit LC1 Inductance Capacitance Meter RAMSEY AMATEUR RADIO KITS HR Series HF All Mode Receivers QRP Series HF CW Transmitters CW7 CW Keyer QRP Power Amplifiers RAMSEY MINI...

Page 3: ...y 6 Parts Layout Diagram 6 Schematic Diagram 7 Testing 11 Troubleshooting 11 Transmitting Receiving 12 Customizing 13 Installation 13 Operating Your PA1 13 Warranty 15 KIT ASSEMBLY AND INSTRUCTION MAN...

Page 4: ...ur final T R installation to boost those hard to copy signals We ask you to understand that the VHF Power Transistor that is the heart and soul of this circuit cannot be guaranteed beyond careful test...

Page 5: ...kside of the board to prevent the part from falling out before soldering The part is then soldered securely to the board and the remaining lead length is then clipped off PA1 PARTS LIST 1 PA1 Printed...

Page 6: ...er step Right now simply position it in place and observe how far its flat leads extend toward the input and output pads Scribe a line into the tinned pads at each end of these two leads as a guide to...

Page 7: ...PA 1 7...

Page 8: ...you can see some finished work on your PC board this is a good time to begin making and installing the three coils and RF Choke 9a Cut a 1 length of 18 tinned bare wire and form it as shown making a g...

Page 9: ...12b Install the RF choke 13 Install bypass capacitor C7 01 uf marked 01 or 103 or 10 nf from the DC voltage pad to the ground plane VERY IMPORTANT PLEASE READ The RF Power Transistor MUST be mounted t...

Page 10: ...ps consist of the CORRECT installation of two small 47 or 56 pf disc capacitors This step is more critical than many builders may realize because excess lead length of C5 and C6 will reduce power outp...

Page 11: ...r a sudden peaking of RF output C2 has the most direct and critical control over the driving of Q1 3 After some power output is noted from peaking C2 then adjust both C3 and C4 for maximum output Then...

Page 12: ...in doing so how dependent you are on factory or professional service and the policy of the service center on modified equipment We developed the RFS 1 T R relay kit exactly for those situations where...

Page 13: ...ll have as much fun using your amplifier as you had building it INSTALLATION NOTES 1 The best location for the relay is as close to the PA1 amplifier PC board as possible with a short solid connectio...

Page 14: ...ent right from the start CONVERSION STEPS 1 Lift the ground side of the RF choke 2 Solder a 1 amp diode s cathode lead banded end directly to the emitter ground connection of the RF power transistor K...

Page 15: ...ur abilities please return it for a complete refund The PA1 kit is designed for the advanced builder who appreciates the convenience of having all the hard to get parts available from one reliable sou...

Page 16: ...y and Instruction manual for RAMSEY MODEL NO PA1 2 METER RF POWER AMPLIFIER KIT RAMSEY ELECTRONICS INC 590 Fishers Station Drive Victor New York 14564 Phone 585 924 4560 Fax 585 924 4555 www ramseykit...

Reviews: