Tuesday, June 17, 2008

600w Mosfet Rf Linear Amplifier with APT5020BN

Ir Eliza Sukiman MM MA
YB 0 BAJ Indonesian Amateur Radio Station

This is my base station of MosFet Rf Amplifier. The MosFets are APT5020BN ,I have used them in my base station and they produce a good 600w from 36V on 160 and 80,and 400w on 7 Mhz. , I've had 600w out of four at 36V on 160 with a one turn primary / four secondary on the output transformer. (Tubing Transformer).
The circuit is basically the same but this is two devices with combiner on each side of the push-pull. The golden rule is to use a fet capable of withstanding three times your maximum supply voltage.

lets see . . . Schematic.

See Youtube 300w ...  Click Here

See Youtube  600w ...  Click Here

See Youtube 800w ...  Click Here

New power-MosFets coming out every week or so, look for ones with a low Rds-on and high power dissipation. The main drawback is the high gate capacitance, several thousand pF, which makes them hard to drive above 7MHz. Check out IRF , IXYS and APT ( FET manufacturers)

Tuesday, May 27, 2008

300w Rf Amplifier using low priced Mosfet

by Ir Eliza Sukiman MM MA
YB 0 BAJ Indonesian Amateur Radio station

I have read Rf Amplifier Circuit using mosfets on the ARRL Handbook 2002. The amplifier used a pair of Motorola IRF510 transistors to generate 5 or 6 watts of peak envelope power from a 48V supply and operated within the frequency spectrum of 1.8 to 28 MHz.

It might be of further interest to describe a higher power version of a linear amplifier which I had reason to design, using two IRFP 150 ,WO12L54F , or other . The Circuit can deliver a power off 250w at 1.8 MHz, 300w at 3.5 MHz and 200w at 7 MHz with 36 v . The IRF150 transistors used  the International Rectifier (IR) .

see . . . Schematic

See demo in ... Youtube

See Youtube  600w  ...  Click Here

See Youtube 800w ... Click Here