HF Amplifier project 4x PL504 parallel tuning output about 160W PEP = 40W AM carrier
Complete schematic will follow when working.
I came with the idea to make a loop antenna for the FM band, from a simple aluminium tennis racket, we want to trow it away .
But it turned out to be just the right size for a loop .
This one works perfect on 104.6Mhz .
You can hide this one evrywhere for your local work.
Watch out with power on this, playing with 5W a few hours you will feel in your head.
I have tested a IRF510 mosfet as amp. in a shortwave TX.
TX is with a X-tal oscillator a driver the IRF510 and a NPN transistor as series modulator in the supply.
The TX works perfect, is was tested on 5.8Mhz and 6.4Mhz .
The max power with 24volts was 30watts and more is possible if you make it 28volts.
Higher voltage than there wil be more heat in your series modulator (to mutch ) and there is no need.
With 30w on peak only using 5w carrier for a strong AM modulation.
You will notice the difference on the audio pressure between 10 - 5w.
When testing on the antenna i made repports all over Europe with only 5Watts.
From the Netherlands to UK , Finland, Germany and Italy in the evening hours.
I must admit there where some nice conditions in the E-layers otherwise it,s simply not possible.
But it gives me nice feeling to get there with sutch a small TX .