TDS540B switches during boot VGA output from color to monochrome


Hi Henry,
I've just sent a PM to you!


Yes, looks the same. Can you provide me with a transformer? I read that you have at least one left. How can I send a PM?
- Henry


see that topic:
I think you have the same problem...


Tam Hanna

Afaik normal behavior. The color 7xx has more memory. But there is a tutorial on eevblog how to work around it.
With best regards
Tam HANNA (emailing on a BlackBerry PRIV)

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Hi! I found my first Tek device, a TDS540B. After approx. 40 minutes the monochrome display collapses, but the VGA output is then still ok. Any idea what is going wrong? Looks like a power supply is going wild.
Anyway, my first question is: How to configure the device to send color to the VGA output. I noticed that during boot time for 2 seconds the output is colored! Even as the internal monitor is monochrome.
Is this device one of the problem childs with capacitor leakage?

Thank you for any help!
- Henry