exxos's Atari, Amiga & retro forum

demonlg wrote: 16 May 2022 16:00 Yes sorry for my english, i'm write from Italy, charge (carico) in effect is load....sorry

Yes the resistor seem to be ok, 8,2 ohm on multimeter.

The original transistors are simple to find on line?

This night i try to make a load with resistor and test it.

Thanks

Emanuel

No need to be sorry, your language is your language, we just need to be sure we're talking about the same thing.

I don't recall the transistor's part number, but you can look at the schematics, and you should be able to find them or a direct equivalent online.

If you are making a load, read the info on exxos store, they'll need to be rated highly enough for 2.2A at 5v and 1.2A at 12v, so you'll need something that can take that power.

I have read on shop:

Contains:
Top rated quality, low ESR, High ripple capacitors.
1x 47UF, 400V - Replaces 400V 47uF
1x BRIDGE RECTIFIER - Replaces 2A rectifier (PCB holes may need drilling with 1mm drill to fit)
2x CAPACITOR, 16V, 1500UF - Replaces all 1000uF caps.
3x CAPACITOR, 16V, 4700UF - Replaces all 2200uF caps.
Kit now also contains:
1x 1K resistor
1x 1.2K resistor.

1x STPS10H100CFP - replaces the output diode pack HRW34 (right side heatsink )

i have replaced capacitor with same value of original and not with 1500 and 4700uf new one!
then the resistor is for?

for output diode pack i have used a MBRF2560CT.

I will find the schematics, now i don't have idea to find it.

Emanuel

I have tested with 10R ceramic resistor connected on 12v output and the multimeter report only dropped to 1,32 volt, without load connected 11,58volt, this confirm the psu problem.

Not test 5 volt output because i don't have 2.2R ceramic resistor now.

I don't know.....!

Emanuel

10R on the 5V should still be enough.. But the regulation is only done on the 5V rail.. So I am not sure how well it would work just loading the 12V.. It's nothing I ever tried.

Is it possible to test the 5 volts with the 10R connected?

demonlg wrote: 16 May 2022 19:49 Is it possible to test the 5 volts with the 10R connected?

That is what I just suggested to try..

Tested now, with the 10R on 5volt rail i have 5,36 volt on multimeter !

Problems on the 12v rail?

When i power on the multimeter start to 0,69volt and then switch to 5,36v.

demonlg wrote: 16 May 2022 19:56 Tested now, with the 10R on 5volt rail i have 5,36 volt on multimeter !

Problems on the 12v rail?

You should be able to measure 12V now.. and it should be about 12V (likely 11.5V).

You also need to adjust the preset pot so you get 5.00V on the 5V rail.

OK, with 10R resistor connected on 5 volt rail and multimeter connected to 12 volt rail i have 11,79 volt.

To adjust the 5 volt trimmer, can I keep the power supply on without problems for a few seconds?