This is 100 watt linear amplifier and may be built using two MRF309 transistors in push-pull, requiring only 16 watts drive from 420 to 450 MHz.
The 100 watt linear amplifier operating from a 28 volt supply, 8 dB of power gain is achieved along with excellent practical performance featuring: maximum input SWR of 2:1, harmonic suppression more than-63 dB below 100 watts output, efficiency greater than 40%, circuit stability with a 3:1 collector mismatch at all phase angles.
100 watt linear amplifier Parts list : Ti & T2 - Balun. Unbalanced to Balanced RG 58, I = 2.5" R1 : 1 k, 1/2 W R2 : 10 ohm 1/2 W R3 : 10 ohm 1/2W R4 : 5.6 ohm 1 W R5 : 5.6 ohm 1 W R6 : 2.7 ohm 1/4 W Z1 & Z3 : Microstrip - W = 200 mils, I = 1 8" Z2 & 24 : Microstrip - W = 200 mils, I = 300 mils Z5 & 26 : Microstrip - W = 150 mlls, I = 300 mils Z6 & Z8 : Microstrip - W = 150 mils, I = 1.4" RFC 1,4 : Ferroxcube Bead 56 590-65-38 RFC 2,3 : 0,16 uH Cambion Molded Coil RFC5, 6 - 1 Turn #20 Enameled Wire Wound on 5/16" Bolt RFC7, 8 : VK200 20/48 C1,3,4,5,7,8,11,15 : Underwood 40 pF C12,16 : Underwood 25 pF C13, 14, 22, 23 : Underwood 18 pF C9, 10, 18,20 : I uF Tantalum C21, 24 : Underwood 10 pF C2, 6 : Arco 403 C17.. 19 : Underwood J102. 1000 PF Feed Thru C25, 26 : 0,1 uF, Erus Red Cap L1 : 24 nH, #14 Wire, I = 1.2" L2 : 12 nH, #14 Wire, I= 0.6" L3 : 24 nH, #14 Wire, I = 1 2" Board : G10, cR : 5. t=0.062" , I = 8.0", W = 4.0" Q1 : 2N5192 Q2 : 2N5194 Q3 : MRF309 Q4 : MRF309 D1 : 1N4001
