Ashhar,
I had 60db of external padding between the transmitter and the SA plus
30db padding in the SA itself.
That should have been about 10 microwatts (10watt/1,000,000) of actual
power feeding into the SA.
Now I have to admit I haven't verified my pads for a long time but I
don't think they are far enough off to make a huge difference since I
was just looking for relative relationships.
And I didn't see any harmonics that weren't at least 50db down from the
fundamental.
I have adjusted my drive level and bias to get as clean of a signal as
possible. That's about 10 watts out on 3290kc. I haven't checked the
other bands yet.
I may diddle with the bias and drive some more to see if I can get more
power while staying clean but I'm pretty happy with it as it stands.
tim ab0wr
On Sat, 24 Mar 2018 18:32:02 +0000
"Ashhar Farhan" <farhanbox@...> wrote:
i hope you guys are using sufficient attenuation ahead of the spectrum
analyzer. typically, if you change the attenuation, the harmonica and
the fundamental should fall exactly the same dbs.
- f
On Sat, 24 Mar 2018, 23:55 Tim Gorman, <tgorman2@...> wrote:
Junior,
When doing a two-tone and single tone test I do not see these
harmonics.
Carrier suppression is not what I would like but no harmonics.
tim ab0wr
On Sat, 24 Mar 2018 09:50:30 -0700
J¨²nior PY2ADA via Groups.Io <aaj280174@...>
wrote:
Testing with the micro bitx in the spectrum analyzer, I found that
the harmonics reduction is very low. Has anyone else done this
measurement to compare? The photos are 3 per band (fundamental,
second harmonic and third harmonic). 73 de J¨²nior
PY2ADA
