[TYPO3-mvc] t3lib_utility_Debug::debug($myVar, 'myName'); no output

[Gerhard Mehsel]

Hello,

I try to debug a extbase/fluid backend modul and have some problems with 
debug output.
My TYPO3 4.7.5 has following settings in install tool:

[SYS][devIPmask] = 127.0.0.1,::1,10.0.0.*,192.168.2.*
[SYS][sqlDebug] = 1
[SYS][enable_DLOG] = 1

A call to t3lib_utility_Debug::debug($myVar, 'myName'); generates no 
output, it even supresses the output of the backend modul as a whole 
(Modul frame is ok, site tree is ok, but content area is a blank page in BE)


A call to t3lib_div::devLog("my message", $this->extKey, 3, $myVar); 
generates no output in devlog extension, but i can see "my message" in 
firebug/firephp, but without examination of $myVar?


Can anybody tell me what I'm missing? Or is there a tutorial, what 
extensions to use for robust debugging messages for FE and BE extensions?

Best regards,
Gerd