Thanks Ron for your interest, yes those sense lines are connected to their respective regulators via two resistors. One is connected to ground and one to Vout. They appear to be working fine tho , they are only low power surface mounted regulators and i dont really need them anyway, as the high power section is now finally working.

I was going to post another thread regarding how to modify the shunt feedback regulator ( IC931) located in the low voltage secondary section of T901 so as to reduce the output on CN902 to ~+14 volts. Its a TA76431AS adjustable shunt regulator IC , i've only briefly looked at the specs for it , but from what i've read so far it appears do-able.

Adjusting the regulator is the way to go, BUT that may not affect the available current, since the power is provided by a transformer whose current rating is not changed.
So you may only have a nice experimenter power supply, not a battery charger type of power supply. And for an actual battery charger suitable for automotive style 12 volt batteries, the transformer types are a better choice because of much greater durability. Of course, those chargers I have all got new rectifiers on actual heat sinks, replacing the "sort of" heat-sinks they originally had.

 

Adjusting the regulator is the way to go, BUT that may not affect the available current, since the power is provided by a transformer whose current rating is not changed.
So you may only have a nice experimenter power supply, not a battery charger type of power supply. And for an actual battery charger suitable for automotive style 12 volt batteries, the transformer types are a better choice because of much greater durability. Of course, those chargers I have all got new rectifiers on actual heat sinks, replacing the "sort of" heat-sinks they originally had.

Update/progress report: Wow hard to believe its been practically a whole year since i got back to the SMPS project.

I took your advice Bill and decided to make it into a DC bench supply instead of a battery charger ( i already have one anyway that i rearly use ). I recently started building the base and front panel and gathering the parts. After putting the board on the "chasis" and powering it up , noticed that the heatsink on IC901-Q901 was warmer than i expected, but not too hot to touch. The original unit had a small cooling fan for the amplifier section but not for the power supply board.
Maybe im being paranoid and this is normal for a heatsink with no load connected ?

Posted a coupla pics of the SMPS project after installing the board on the "chasis ".

 

A small fan will really help the cooling air circulate, and depending on what you find it may not use much power at all. OR a slightly larger one, that uses mains power directly, will not load the supply at all.

 

Thanks Bill for responding. I still have that original small cooling fan , its runs on 12 volts dc @ 0.6 watts so very low power and runs extremely quiet. I just have to make a mounting bracket for it and attach it to the base near the larger heatsink. So i guess the warm heat sink is nothing to be concerned about ?
Ive attached a pic of the cooling fan for size familiarity.

 

If a heat sink did not get warmer than the ambient temperature it would not be doing any good at all. The only purpose of a heat sink is to absorb head from some source and distribute it elsewhere. And to do that the temperature must increase. There is a huge amount of math than can be applied to the discussion but it gets rather tedious.so if you want the math proof be prepared for a lot of tedious equations.