Most Solid state power amplifiers I have seen have between -20 to -26 dbc
harmonic output
specs.
Look at a real amplifier manufacturer ENI. http://www.enipower.com/
They only spec their harmonic output on most of their products to be better
than -22 to -25 dbc at 80% of maximum power output for their class A
amplifiers.
When you tested the amplifier you mentioned did you test it above 15 or 16 MHz?
If so then a 30 MHz Low-pass filter would filtered out the harmonics. If
tested at
say 7MHz I expect it would have considerable harmonic output.
73
Bill wa4lav
At 09:40 AM 1/21/00 -0700, you wrote:
>Most of the solid state 2 to 30 MHz ones are actually quite good
>as far as harmonics are concerned.
>
>As long as they are not over driven.......
>
>As a precaution it would still be wise to run the output thru a Pi L
>type antenna tuner and a low pass filter to clean up any possible
>harmonics - a lot of harmonic content can be even generated in
>the QRP rig and is not a problem until it is amplified.
>
>Least thats what the spectrum analyzer says for a Palomar TX-75
>and a number of others that I have worked on.
>
>I have seen a lot worse on the air from both commercial and home brew amps
>being improperly tuned, - over driven, -and poorly designed etc.
>
>73
>de
>ve6nap@oanet.com
>
>----------
> > From: William Fuqua <Wlfuqu00@pop.uky.edu>
> > To: amps@contesting.com
> > Subject: [AMPS] CB amps on ham bands?
To: <amps@contesting.com>
> > Date: Friday, January 21, 2000 7:35 AM
> >
> >
> > I am seeing a number of "CB" solid state amplifiers being sold on ham
> > reflectors now days.
> > These are advertised to be useful from 2 to 30 MHz. One example is an ad
> > for a Palomar #225 that I saw.
> > However, many hams do not realize that these do not have output harmonic
> > filters incorporated in them
> > for the various ham bands. I expect that they produce serious harmonic
> > output if they are used on the
> > lower ham bands if used with QRP rigs. I suspect that the ads are
>really
> > targeting CB'ers.
> >
> > 73
> > Bill wa4lav
> >
> >
> > --
> > FAQ on WWW: http://www.contesting.com/ampsfaq.html
> > Submissions: amps@contesting.com
> > Administrative requests: amps-REQUEST@contesting.com
> > Problems: owner-amps@contesting.com
> > Search: http://www.contesting.com/km9p/search.htm
> >
>
>--
>FAQ on WWW: http://www.contesting.com/ampsfaq.html
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|