Hello
I'm a newbie into RF.
I bought a broken Mini Circuits ZHL-10W-2G+ amplifier that I'm going to attempt to repair. It's labeled "EMC lab" so I think its been used for EMC. I don't know what happened to it, load mismatch? If I can repair it I'm going to use it for immunity testing.
The switching pre-regulators have released their magic smoke. The last two power stages all have a short between source and drain, no visible damage.
After removing the pre-regulators(bypassed them with a blob of solder), and shorted transistors, it will power up and the linear regulators are regulating.
I put rf into the input(HP 8753B) and the first 2 amplifier stages(green) seem ok. The signal is larger after each stage.
There is a component circled in blue that I'm not sure what it does?
The power transistors are somewhat expensive so I figure it's best to ask here before I do anything. Are there any, "traps for young players?"
There are a couple of multi-turn trimmers that I guess are for biasing of the transistors.
/Erik