not enough power?

[mischl]

hello dave and steve

thanks for your replys. i need a bit of time to answer because i must test all seriously.

i'm no a step further. the problem seems not to be in PSU... i made a mistake in the software which have updated the outputs too fast and this problem sourced. normally the output at the 7805 is stable at 4.9 V

now a new thing is coming up. all is working but i'm not sure why this can be :
the circuit needs 16 mA @ 5 V. when i turn on a reed relais it needs 20 mA more, so 36 mA. the next relais add also 20 mA, all is fine.
now, when i turn on the third relais and the current increase to 76 mA, the 5 V looks at in the attachment...?

the relays are connected at portb, which have beside the relays only two led's (r=330ohm). the datatsheet says a maximum output current sunk by a pin is 25 mA, maximum current sunk of porta and b is 200 mA. but the whole circuit only needs about 90 mA when all is turning on.
the trafo output is 6V 1.0 VA.

as i say it. the circuit works, but i ask myself what is that?

thanks for any comments again