The most common modern device for HF amplifiers of about 50W is the rating, and the Fairchild part having a track record in citizen band radio output stages.The IXYS FET is only available through Mouser in the UK, and has a higher voltage rating.A DMM is expected as is a variable amplitude & variable freq. To build the better Amp (the hacked one) use the LTspice schematic in the files link to match component values to the supplied PCB silk screen parts. Note the logs below detailing an alternative build mod#2 that improves the purity somewhat esp. THE Mod#2 LTspice file carries all the details there.Now I HAD to swap a 2n2222 in for the input transistor as i accidentally killed the OEM unit while experimenting. Note the 'dead bug' installation of the 2n2222 in the pictures You can try it out without swapping the input Tranny Q3, it should be fine as is. Also note the wire jumper installation replacing the T1 transformer and the 470Ω through hole resistor used to 'jumper' the Q3 base to SMT R4.
Eventually expect to draw a bit more than 5A at full...The amplifier section is on the left, filter to the right.If anyone wants a low-pass as a separate project, it can be split off by cutting along the dotted line!FETs designed for switching power supplies are not ideal but cheap, so I embarked on a project to find a usable part, and make a low-cost amplifier using it.Blank PCBs (150x100mm) for the project are as shown here.