SSLV1.1 builds & fairy tales

[merlin el mago]

Salas there is some self power consumption of reg. to work OK, I measure circa 650mA @ R1 ande the load is 600mA?

 

[Salas]

I have a suspicion this one at least maybe has a difficulty so compare with resistor plate load also for bias behavior

 

[Salas]

Salas there is some self power consumption of reg. to work OK, I measure circa 650mA @ R1 ande the load is 600mA?

Can typically regulate even on such a small spare mA margin, eats only few mA for itself. More spare mA is simply burning it for better output impedance spec.

 

[merlin el mago]

Ok I will compare vs resistor loaded to see how works t'he battery bias, 5K6 resistor, 200V B+ and 150V at anode?

 

[merlin el mago]

Thanks now I am confident with the reg. for heaters.

Could I ask what do you think of bias point choosen or let me know what do you like more?

TIA

 

[Salas]

Ok I will compare vs resistor loaded to see how works t'he battery bias, 5K6 resistor, 200V B+ and 150V at anode?

Sounds like a good config to find the right -bias Voltage for grid at 9mA plate current so 150V on anode.

 

[merlin el mago]

Thanks for input, I will let you know how goes, I'm sorry for the OT.

 

[merlin el mago]

It seems the BiB powering heaters is oscillating. Attached pics measuring AC & DC.

 

[merlin el mago]

Time to use a dummy load 10K500 to see if still oscillates.

 

[merlin el mago]

Vids with the dummy load, no oscillating. It's strange the cable is twisted and fixed to the chassis.

 

[merlin el mago]

Isn't the wire.

 

[Salas]

Maybe you need set bit more spare current?

 

[merlin el mago]

Could be, that's the reason I asked you.

 

[merlin el mago]

With 700mA still oscillates.

 

[Salas]

Maybe the heater negative is not grounded ?

 

[merlin el mago]

Near 800mA still oscillates, could be the issue Zobel network related, because several times the tester reads 1 or 3 volts: I said because the zobel used is 4.7uF in place of 10uF?

 

[merlin el mago]

Maybe the heater negative is not grounded ?

C305 negative capacitor is chassis grounded.

 

[merlin el mago]

See what happens when start power 1st pic left side measuring DC, 2nd pic measuring AC: 50Hz near 3V, 3rd pic once stabilized measuring DC, 4th pic measuring AC once stabilized.

 

[Salas]

How much Vin it gets?

 

[Salas]

Last one says 0Hz after stable so not hum but 66.7mV noise even if white noise its no good.