capacitors across dropping resistors?

[mich]

Hi,
I have a stereo hi-fi tube amp on the bench - that have big electros(100uF) in parallel to the droping resistors.
its a tube rectifier (ez81) power supply with a choke and there is one cap across the choke and one across the last dropping resistor
there is only one 50 uF cap to ground right after the choke.

as i have never seen this before - could someone shed some light on this ?

 

[emrr]

Are you sure one side of the choke isn't ground?  It would make sense then. 

 

[moamps]

Hi,

that's maybe a resonant choke power supply.

http://www.qsl.net/i0jx/supply.html

Regards,
Milan

 

[Nora]

You sure it's not a dual capacitor?
They have 3 terminals and many times the series resistor in places between two terminals, the third terminal is common and connects to ground.
That would make sence...

 

[mich]

no,the choke isn't grounded.i double checked.

and the capacitor is a dual  , but with 2 terminals - one of them not being used  - and the case of the cap is the ground.

but that resonant choke power supply seems the case.(thanks for the link)
it does not explain the dropping resistor though..

at this point i have to say that this power supply works and works good...
there was some hum only with unbalanced output tubes - when matched its quiet.