Hello friends,
This is my first post.
I'trying to modify a Nokia PA with 2 x BLF8G22LS-160, it works but I don't understand why I have only 18dB of gain.
I get, with 18dbm of input, 36dBm of output and with 25dBm (max input for SPB2026Z) of input, 43dBm of output.
If the first chip SPB2026Z was damaged the signal wouldn't be amplified!!
I saw the datasheet of this chip and this need of 5Vbias on pin 1 and a minimum of 0dBm but I don't understand Vpc but I measure Vpc=2.3V with and without signal.
I tested the Vg for each ldmos, on the driver I measure Vg=2V, the central final ldmos 2V the other finale 1V.
Are they correct?
Is it possible supply bias by external with a zener e trimmer and what resistance should be removed?
73 de IZ1QXJ
Antonio