[1000mp] Important question

[Hans Remeeus]

Hello Noel,

The best way to reduce harmonics is to use a good Low-Pass Filter. A 
good Antenna Tuner will be helpful too.

When I transmit with my Field on 3.500 MHz at my dipole antenne and 
receive its harmonics on my FT-1000D without external antenna, I have a 
S9 signal on the 2nd, 3rd and 5th harmonics and a S9+20dB signal on the 
7th harmonic. This is with a Low-Pass Filter.

When you use 100 Watt and have a harmonic surpression of 80 dB (which is 
very good!), than you still have enough power output to receive a strong 
signal on a second receiver at the same location.

Try to receive your harmonics on another location, less than a mile from 
yours. You still will receive some of the harmonics from your 
transmitted signal. Just a few remaining milliWatts will be sufficient. 
Depending on the frequencyband where your are transmitting on, the 
signal strength will vary.

Or try to measure your harmonics on a spectrum analyser. You will see if 
this is within the specifications of your rig and the demands of your 
administration. In our country we have to have a harmonics surpression 
of >50 dB on HF.

73.
Hans Remeeus (PA1HR)
http://www.remeeus.nl
Communication is about people, the rest is technology.




NOEL POULIN schreef:
> Hello Everybody
> I wonder what is the best way to reduce harmonic from a MARK FIELD  on 40 meters for example, and another FIELD on 20 meter ...
> Is it normal to have a reading of S9 on 20 meters(example14.078) for 100 watts out from the second MARRK V at 7.039????
> Please any advice will help a lot
> Thanks
> NOEL 
>
>