Service manual

1
I N T R O DUC T I O N
My interest in CB conversions began some years after Lou Franklin first published his
"Screwdriver Expert's Guide" and "The CB PLL Data Book". Consequently I was able to
read these and progressed quickly from having a passing interest in CB to actually running
a repair business and publishing a quarterly newsletter for like-minded individuals. Lou's
books have been a guiding influence in my hobby-turned-business and I am in no way
putting them down when I suggest that they lack just one important chapter. I hope that this
book will fill that gap and help you as much as Lou's books helped me.
This book assumes that you have read "The CB PLL Data Book" and have a basic grasp of
the way in which a PLL frequency synthesiser works. The use of an Eprom will allow you
to utilize the standard channel switch but to program the codes which will make the rig
operate on whatever channels, in whatever order, that you wish (within the limitations of
the rig itself). Most modern AM or FM CB radios use a dedicated PLL whose codes can
not be altered. Sideband rigs, however, can almost always be converted for 10 meter
operation because they still use the type of PLL which has a wide choice of codes. Even
those with dedicated PLLs can often be altered if an Eprom is used in conjunction with a
different PLL.
The book will be of especial interest to those who are looking for a low cost entry to the
American "Novice" band.
© Copyright 1987 by Martin T. Pickering
This book is for all those CBers and Radio Amateurs out there who like to indulge in the
practical aspects of the hobby.
My grateful thanks are due to my wife, Gill, for her patience; to my kids, for keeping out
of the way; to Brian Spiller , who suggested the idea and checked the proofs; to my brother,
Rob, for the use of his computer; to Chas for the use of his laser printer and to Lou and
Sally Franklin for their continued support.
Dave Addy designed and drew all the PCB layouts and their circuits.
Cover design and “Gang Bang” drawing by:
Studio 3, Palace Vaults, Plymouth, PL1 2NA, England.
Other sketches by Martin – drawn large then reduced down to hide the defects!