I have been reading this group for a while, but have just joined. Thanks for the add.
I've been a ham for only a couple of years, so this has been a lesson learned:
A couple of weeks ago I was experimenting on JS8 with a new antenna and produced enough
common mode current to fry my Raspberry Pi and uBITX. The RPI was replaced as were the finals
in the uBITX, but I had only about 1W output. I replaced the finals a second time, but the low output continues.
I downloaded the Diagnostic Guide and have measured all the TX Testpoints (Thanks Farhan!).
Using a battery at 12.3 VDC to power the uBITX, most Testpoints' measurements showed voltages slightly higher
(+ 0.1-0.4 VDC) than the values listed in the Guide.
Others showed these differences:
Q911-3, Q912-3, Q92-3, Q93-3, & Q96-3 measured 11.9 VDC instead of 10.9 VDC.
Q94-2 & Q95-2 measured 12.3 VDC instead of 11.3 VDC.
Q94-1 measured 12.3 VDC instead of 3.1 VDC.
Q95-1 measured 3.2 VDC instead of 3.3 VDC.
U2-1 measured 5.0 VDC instead of 4.2 VDC.
U2-3 measured 12.2 VDC instead of 10.9 VDC.
I've examined the components leading up to Q94-1 and they all seem externally okay to me. My ohm meter says they are
connected from one to the next.
My only electronics education is from reading and small experiments (I was a registered nurse before retirement), so I don't really know what to do next.
Can you all please help me figure this out?
I welcome your suggestions!
P.S. I've constructed a toroid choke balun!!