UMTS PA from Fojutowo Microwave Meetup

The amplifier board comes from a commercial 2100-band cell amplifier. I'm planning to retune it to 2400 MHz for QO-100 DATV operation.

Board layout

1. Signal input
2. MW6S004NT1
   • RF N-MOSFET
   • wideband matching (datasheet says "up to 2000 MHz" - lol)
   • 18 dB gain, P1dB >+37dBm (nice), 28V
3. IL05AL(R)2140AAE
   • 2.14G isolator "2G14 P4N"
   • 0.6dB loss between 2110-2170 MHz
   • 10W FWD max
   • 2.4 GHz attenuation? I guess not more than 3dB & poor isolation
4. X3C21P1-05S
   • 5dB splitter for 2000-2300 MHz
   • maybe wideband just enough - DS ends on 2300 MHz
   • ideal replacement: X3C25P1-05S (2300-2700 MHz) - 4€ @ Mouser
   • why 5 dB? need to figure out the layout (Doherty amplifier..?)
5. AT2S15N / AFT20S015N
   • 1800-2700 MHz, N-MOSFET
   • ~17 dB gain @ 2100 MHz, P1dB 16W, 28V
6. AFT21S240-12S
   • N-LDMOS
   • internal matching 2110-2170 MHz
   • ~20dB gain, P1dB 230W, 28V
   • datasheet page 7, 2400 MHz: >20dB gain, -10dB IRL
7. [SKYFR-000819]
   • 0.5 kW 2110-2170 MHz isolator
   • to be replaced with a piece of semirigid coax?

Steps

• remove one of the small silver filters and measure its frequency response
• supply bias voltage to the respective stages, possibly by reusing the AMC7812 chip instead of homebrewing own bias solution
• read AMC7812 datasheet, check if it has some kind of internal memory
• identify left-hand-side connectors (where's the main VCC? top left?)