Testing Power Output of My Homebrew HF Linear Amplifier, VU2EVQ Design

| February 10, 2026 | Amateur Radio (Ham Radio) | No Comments

Lineup for this testing:

5W set in FT-710, AM Mode, running on 12V LiFePO4
10m HLF 200 patch cable from radio to linear amplifier
VU2EVQ Design HF linear amplifier
ATU-100 External Antenna Tuner through 50cm RG58
Homebrew common mode choke
Air core balun of 15 turns RG58 on 4” PVC
15m RG58 feedline
Inverted V 40m antenna with apex at about 10m
12V SLA battery from 300W offline computer UPS

Standby Bias Setup in Linear Amp

3.27V for one IRFP150
3.28V for other IRFP150
Idle current without bias ~ 15mA
Idle current with bias ~ 48mA
Supply voltage 13.25V on standby load