600 PA project :
the transmitter to a higher band,
FIRST change the LPF in the PA also to that higher band.
If failing to do so, DAMAGE will oocur in the PA, as while turning up input power, NO output will be seen.
CAUSE : the output power and refelected power indicator circuit is located BEHIND the LPF. The LPF does not give output.
All 864W power will then be dissipated in the FETs. => @#*^%$ !
|.2.||A magnetic loop antenna has a narrow VSWR bandwidth. When the TX is accidentally mistuned to another frequency than a narrow band loop antenna is, you can harm the PA.|
|3||When using SDR
software, you can easily jump to an unwanted frequency,
by accidentally clicking on a wrong place on a screen.
Use a foot switch to activate the TX.
broadband amplifier can show nearly 600W output on the meter, by driving it with more
power than 1Wrms. But this is not advised.
Maximal drive power.
Driving this amplifier with more than 2.6W
damage the gates of the FETs.
Also : replace D6
by a fast +/-5v bipolar surge arrestor diode CDSOD323-TO5SC .