SSLV1.1 builds & fairy tales

After changing it and you check that the tabs on both MOSFETS show no continuity to chassis once again, remeasure drop across the 10 Ohm R101 so we will know the new current, also feel the heat transfered to chassis so we decide if to short the fourth LED or not. Basically for a 53mA bias we will need 3 times that for full swing plus some spare that we will evaluate how much can we allow to our benefit based on idle thermal behavior.
 
Check the CCS current and the CCS voltage drop, when you have no load and when you added the load.
Repeat these two tests when mains voltage is down to the minimum from your supplier.

I think your 22Vac transformer is too low for a 24Vdc shunt style regulator.
 
Replace Q101 and Q106

Can get 24V

Voltage drop at R101 = .39

temperature at mosfets = 38C

temperature at R101 =50C

Ground to source =30.14

Source to gate = 9.1

Works 🙂

9610's VGS maybe less than 9.1. 4-5V would compute better.
390mA now i.e. logical value and ample spare for having low rail modulation THD (good thing). At 38C semis you may keep it. If you also got about 5VDC or more between Vin to Vout you are OK.
9610's Source to GND already indicates enough. You can measure Vin between R101 input pin and GND. Vout is 24V of course.
 
Yes, success with the first one! Now three to go (dual supplies). Should I change R101 to a higher wattage, the heat on it makes me nervous.


I see the thread: TPS7A4001 vs Salas shunt Reg

I wonder how customer service is with that Reg?😀

Thanks again Salas!
 
Mosfets

I'm ordering more mosfets. I've only used the mini-kits from Teabag before. Is there a difference in this circuit between the older vs the newer ones (i.e. IRF530 vs IRF530PBF)? Looking at the data sheet they look identical to me, other than the PB being lead free.
 
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