Author Topic: BSIAB2 is not powering up with battery and biasing 2n5457 problems  (Read 1460 times)


What could be the normal cause of a GGG BSIAB2 not powering up with a 9V battery. It does power up with a DC adapter but not with a brand new 9V battery. I did a continuity test from the battery terminals to the input jack and DC terminal and its ok. However, its not powering up. Could it be that the Silicon Diode is shorted or open?

THe other problem i have is that the 2n5457 transistor on Q5 is not biasing correctly. Turning the Trim pot from one point to another only allows me to bias the transistor from 6.1 volt to 7.2 volts.