thanks for your interest.
I tried to use the troubleshooting chart but it doesn't seem to be enough for this case. In fact, troubleshooting procedure says:
Q:
"Does the Scope display the power-up screen?"
A: Yes/
Q:
"Does the Scope pass all the Diagnostics?"
A: No, but it doesn't display any result message. It freezes at the Power-up Screen.
Continue with:
"Perform Module Insulation Troubleshooting procedure"
...and here is why I'm saying it is not enough....
Next: "Module Insulation Troubleshooting procedure"
which begins whith a note:
"This procedure assumes that the oscilloscope displays power-up diagnostic messages"
Q:
"Does the power-up screen report any errors?"
A: No, but it doesn't display any result message
Result:
"Oscilloscope is operating Ok" Which is false.
Perhaps, I'm missunderstandige something...
I thought there should be "hold down key" to restart the tds like in the next Tek FAQs link:
"My 11402 has locked up. I have tried powering it off, then on again with no success. How can I resolve problem? "
at: **broken link removed**
but I'm not sure if there is something like that for TDS3000B series...
your posts are welcome.
electron1999