Rohde & Schwarz NGSM 32/10 Power Supply FAULT

[jemp]

Hello Everyone,
bought at HamFair a defect Power Supply R&S NGSM 32/10
by inspection, found a defect 7805 Regulator ( PCB heated very black ) N307 on Regulator Board
this is the NetSense Regulator and gives 5V out  ( 5VMC ) for the CPU and some drivers, and frontpanel PCB
when replaced, PSU works perfectly in all the functions, but  ...  the regulator gets very very hot even since the first 10 minutes...  so abnormal !! ( hence the Blackspot op PCB )
The input is +/- 12-13V and current is 520mAmps, so dissipation +/- 6-7 Watts..
Can someone check if this is normal ?  or should the current be much less..
I checked every load and Display = 250mA - Regulator Board itself = 220mA en IEEE board +/- 50-100mA
If anyone has an idea.. much obliged.
Schematics in annex !
JP

[m k]

What kind of a heatsink, picture?

[jemp]

See pictures

[m k]

A regulator designed by a support logic designer?

Power by it self is not anything unusual but dissipation of excess heat is a bit limited.
Maybe regulator's input voltage is much more than originally expected.

[jemp]

it is 12V and circuit draws about 500mA, so 3.5 Watts is dissipated

[jemp]

question was.. if the 500mA is OK, or too much..
Will place a 10Ohm resistor in front of it.. so 5V wil drop down

[m k]

500mA is not too much for the regulator.

For exact rise of the temp you need exact datasheet.
20C/W is sometimes used and if that is the case then rise is 70C above ambient temp, a bit more than insignificant and obviously must be dissipated by a proper heatsink.

[junioroqc]

my device same problem

[jemp]

So normal then ?
No so great design, from R&S, which suprises me

[Hamelec]

You should check whether one of those famous yellow tantalum capacitors is getting hot and drawing too much current..