Aikido octal floating output

[jeekee]

Hi guys,

I've got an aikido octal all-in-one running and noticed that my output is drifting even though measured after the DC coupling output caps (russian PIO's). Any idea's what might be the problem here?

Cheers

 

[Rundmaus]

How did you measure it to be 'drifting'? Was the output left open or connected to another device?

If left open, does the output of the Aikido have any resistor after the output cap referencing the output to ground? The results of leaving this resistor out have been discussed here before...

Greetings,
Andreas

 

[jeekee]

Output was directly coupled to the oscilloscope (so not connected to a poweramp). I've got the output resistors in place as suggested by Broskie.

 

[jgf]

I had the same problem with mine (cathode follower only version.) Turned out the RC filter at the output is letting low enough frequencies through that perturbations of the line voltage were affecting the output. I went to a regulated supply, which cured the problem.

 

[jeekee]

Thanks JGF,

Unfortunately I've already got a regulated power supply for both the HV and LV part. Also the output just randomly shoots up from time to time almost like one of the caps was dicharging every few seconds...

 

[DF96]

Look for instability in the regulators. Or serious flicker noise in one of the valves?