Hameg 203-7 problems

[ThorCW]

I recently received hameg 203-7 scope and the traces do not show up. Ive checked the power supply and the rails everything seems ok. I did check the lower voltages on the back of the crt I found the vr206 pot was way out of adjustment. Put that back in spec now if the scope is left on for 10 minutes if you cycle the power a trace appears then go right away. The other voltages seems a few volts low but still in spec. Any ideas?

[ThorCW]

New revelation in the Hameg scope. I acquired a high voltage probe and measured the high voltage and after the second measurement the traces were there and have not went inop since. I have also unplugged from power and let it sit and the traces come right back. So anyone happen to know the science of this?

[silverlego3]

Here is the service manual for that scope,not sure if you had it when you checked the voltage rails. 
http://data2.manualslib.com/pdf3/57/5634/563302-hameg/hm_203.pdf?056286f123711c821f7e37942a5e52a3

[ThorCW]

I did have that. The voltages were all within spec but when I touched the lead to pin 3 on the crt board it lit right up and has worked ever since.

[tronde]

You will most likely find some weak solder joints on the CRT socket, or that the contacts in the socket have lost some spring tension.