So we can see some ripple with ghosting inside. Seems like some instability or noise. Experiment until cleaned result.
You know the knobs scale. I can't read directly off the screen, its not a digital scope. If this CCS plate load does not like a CCsed reg and they react, use something else. Or try local decoupling, alternative Fets, higher value gate resistors, tubes etc. to see if it can get better.
4K7 resistive load
50mA SSHV2 CCS
68mVAC ripple
150Vout SSHV2
32mA load powr consumption
No CCS load used
50mA SSHV2 CCS
68mVAC ripple
150Vout SSHV2
32mA load powr consumption
No CCS load used
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It should work for such as many mA. Or towards there. Available voltage across is little (VGS of MOSFET playing that role) that is why the JFETs don't reach their normal condition IDSS in that cascoded circuit you use as plate load. JFETs with small Vgs (off) give relatively more mA at low VDS across. Its shown in their curves. Reaching saturation faster than others.
Salas I investigate the reason SSHV2 don't works very well with CCS load, in the schematic used the cathode bias used is a battery between the input & the grid. Could be the reason?
Could be. I haven't used the specific application to tell you for sure. Or if it works better with some variation.
