CBC International -Tri-Power Linear Amplifier Plans
Introducing the TRI-POWER Broadband Mobile RF Linear Amplifier Detailed
Completely Rewritten & Redesigned for the 1990s &
Beyond. Easier to build than ever.
The RF amp plan has been available since 1979. Now the first major revision since then, and
CBC is really proud of it. The original amp plans were certainly OK, and worth the low price. Thousands were
sold, and people liked them. But CBC always trying to improve their stuff. That old amp was our first try at
this, and had a few design problems and hard-to-find parts that made it tough for the average guy to build.
Boy, we’ve learned a lot since then!
All the old trouble spots have been cleaned up or fixed. Each of the three power options has been thoroughly
tested. The amp is now even easier to build using currently available parts. Especially since we can also offer you
the finished Printed Circuit Board, ready to stuff and solder. Hundreds of happy customers have already written to
tell us how smoothly this new version went together, and how well it works.
The whole booklet has been beefed up the too, from 22 to 28 pages. All professionally written
and illustrated. Why settle for a few pages of illiterate junk from other so-called "publishers?" Get the
real thing for the same price! And as always, you get the CBCI promise of "Satisfaction
The minimum cost to build a complete amp (including our plans & PC board) is about $100,
depending on the power transistors you choose, how good you are at shopping for parts, what parts you already
have laying around, etc. This compares favorably to the typical "$1 per watt" price of ready-made commercial
amps, if you could find them.
· Broadbanded (3-30 MHz) push-pull design. No tuning required after a simple one-time setup
· Three power levels: 60-100-120W (100-140-180W PEP), depending on the transistors you
install when building.
· Includes trimmer
adjustable input and output tuned circuits for
perfect SWR matching. Just set it and forget it.
· All mode operation: AM, FM, CW, SSB.
· Internal SWR protection with rugged Motorola transistors.
· Bias switching lets you choose the most efficient method for Class C (AM/FM/CW) or Class
AB (SSB) operation.
· Carrier operated T/R relay with separate drop-out timing delays to automatically match
AM/FM or SSB operation.
· Switchable ON/OFF operation with LED indicator.
· Jumper adjustable input network matches 4-10W RF drive levels for most popular low-power
· Transient spike protection in mobile use.
· Double-sided PCB design uses extra heavy 2 oz. copper laminate for excellent RF stability
and voltage regulation.
Not Legal For 27 MHz (Class D) CB Use
And it’s illegal to sell ready-made Linears or even amp kits in the USA. Please don’t ask
us about them. The plans include reliable parts suppliers for everything you’ll need to complete this
project, and have great fun learning too.