[Amps] plate power supply drops down after putting new tubes(poor bias current flows ).

[Behiels JeanPierre]

Hi members;

After putting some new 3-500Z tubes I could only obtain a very small bias current of approximatly 60mA !!
Nothing is getting hot after power on for long time and running at "standby position" hi. 
the anode voltage measuring instrument on the front reads 2200 VDC and with key down withou drive power it drops to 1150VDC  with poor bias current of 60mA ??
The bias current should be 200mA by no anode voltage drop !! 
Could it possible that the 1200VAC transformator has loose his life,without obtaining any failure after 25 years of age on this unit ?
Or do I must search for bad rectifier capacitors ???
Same I have with the frontswitch (other HT power supply tap) in the SSB setup !!
Or do I have some of the series  rectifier diodes witch are are gone in the rectifier brigde ?
Do you have any suggestions who put me in the good direction in first instance ?
I do not have really a good fysic charge to put after the rectifier brigde to see if the supply can deliver this power of 220VDC at 650mA plate values
I wish to be sure before changing capcitors due newer ones.
Are there any measurment suggestions witch I can do at this level without any kind of resistance charge (witch I do not have for this HT purpose)  
Behind that are all other supplys and electronic in good condition and work well,I presume.
Pretty dangerous also and to be carefull at this stage !!


Regards Jean ON4AEF.