please post following

Glen Zook gzook at YAHOO.COM
Wed Sep 19 19:07:22 EDT 2007

You just don't get it!

Yes, use of such an amplifier by a licensed amateur
radio operator operating within his/her privileges is
perfectly legal IF the spectural purity of the unit
meets 47 CFR Part 97 Section 97.307.  This is a

Unfortunately, the vast majority of such amplifiers
built for the "illegal" market do NOT meet the
technical specifications of 47 CFR Part 97 Section
97.307.  As such, they should NOT be used until they
can meet the FCC specifications.  This generally means
modification of the unit.  A goodly number of these
"CB" amplifiers are not really "linear" in their
amplification and therefore produce all sorts of
spurious signals.

Now there are a VERY few of these amplifiers that are
of sound design even though they cannot obtain
certification for use on the amateur radio bands
because of drive levels and the fact that they can
amplify signals within the "CB" band.  Now until late
last year when 47 CFR Part 97 was modified it was
illegal to commercially produce any amplifier that was
capable of amplifying a signal between 25 MHz and 35
MHz.  Now it was legal for an amateur to modify a
linear for 10 meter operation as well as any
amplifiers that were commercially produced before 28
April 1978 were exempted.  In addition, home brew
amplifiers built by licensed amateur radio operators
were also exempt from these regulations.

The new regulations restrict commercially produced
amplifiers from being able to amplify frequencies
within the "CB" band but now allow amplifiers with 10
meters to be again produced.

Way too many of these "CB" type amplifiers produce
"buckshot", "splatter", distortion, and so forth,
especially when operated anywhere near the published
power levels.

The fact that most of these amplifiers use sweep tubes
has nothing to do with the problems in signal quality.
 There are a number of bonified amateur radio
amplifiers (i.e. the Dentron GLA and GLB series) that
use sweep tubes.  Also, the ARRL published several
sweep tube amplifier designs that appeared in QST, the
ARRL Amateur Radio Operator's Handbook, the SSB
Manual, etc.  In addition, there were such designs
published in 73, CQ, Ham Radio, and other magazines. 
But, these designs met the FCC technical

Yes, there are those amateur radio operators who are
using the "CB" type amplifiers.  Some of those are of
the "better" designs that operate properly.  Some of
those have been modified to meet the technical
specifications.  Unfortunately, especially on 10
meters, there are a number of operators who are using
these types of amplifiers without any modifications
and, to put it bluntly, their signals "stink"!

Again, it is PERFECTLY for a licensed amateur radio
operator to use these "CB" type of amplifiers so long
as they are operating within their privileges and IF
the spectural purity of the emissions meet 47 CFR Part
97 Section 97.307.  But, if the amplifer does not meet
those specifications then it is definitely ILLEGAL to
use the amplifier.  If the amplifier can be modified
to meet the technical specifications then it is most
certainly fine to use it after it is modified. 
However, to use the amplifier when it does not meet
the specifications is illegal.

Glen, K9STH

--- RAY FRIESS <rayfrijr at> wrote:

Well of course .. that makes sense.  The purpose for
which they were built was for 11 meters.  Any amp is
illegal on 11 meters.   However, if you used them on
the 80 to 10 meter bands, I don't think they would be
illegal would they?
It's like the Palomar 300 which uses six sweep tubes
and puts out nearly 600 wattts.  Everyone knows the
purpose they were built for, even though they have a
bandswitch for 40 through 10.   Using one of those on
40 through 10 would not be illegal.  In fact, I have
talked with hams who use them on those bands. And, if
you took the Palomar circuit diagram and built one
from scratch, the is not illegal either is it?

Glen, K9STH


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