Designing MOSFET amps
I made a model for the 2SK669 and tried it out. First the simulation then the actual circuit build.
This is probably the most common circuit you will see. It is high current, high power and probably not to sensitive.I will be using ear buds or phones and don't need a lot of power and will be driving it with a DBM which is a small signal. A non scientific simple test I ran was to pick up a cell phone and go to setup - about the phone. It displayed a signal strength meter. At the time I had 2 of 4 bars and the reading said I had a 2 uV signal. If we have a 7 db conversion lose with 2 uV in we will be dealing with 1uV AF input. Hopefully we will be receiving stronger signal but it was just something to consider.
NOTE: My digital scope lowest scale is 20mV so I couldn't drive with 10mV but it does show the amp to function.
NOTE: I reran the test an the results match the sim.
The .ASC file for the amp
the .ASC for a RF Amp using 2SK669