I've just been given a new power supply unit from a computer. Apparently something broke so the friend had it replaced and gave me the old.
I think it was just a fuse or resistor as he plugged it into 240 V when it was switched to 110V.
It's a good quality part with fan and many parts inside. Will have a further loook when I get home.
It has a 12 V DC outlet at 18 Amps (that seems too much)!! And 5 volts also. I will check them out.
Looking through the grill now, I see some regulators. Maybe many good parts I could use. I can't see or smell anything burnt.
Fan, led, switches also.
and many wires. I will open it up and check it out.
I think it was just a fuse or resistor as he plugged it into 240 V when it was switched to 110V.
It's a good quality part with fan and many parts inside. Will have a further loook when I get home.
It has a 12 V DC outlet at 18 Amps (that seems too much)!! And 5 volts also. I will check them out.
Looking through the grill now, I see some regulators. Maybe many good parts I could use. I can't see or smell anything burnt.
Fan, led, switches also.
and many wires. I will open it up and check it out.
Brit,
I have been saving my old power supplies for years.........I must have 5 or 6 of 'em laying on a shelf in the garage. Please start a new thread when you build this one up. (into whatever)
Here is a link to a "How to" for building a "Lab" powersupply.
Linkky
Ron
Someday I'll build one too. 
I have been saving my old power supplies for years.........I must have 5 or 6 of 'em laying on a shelf in the garage. Please start a new thread when you build this one up. (into whatever)
Here is a link to a "How to" for building a "Lab" powersupply.
Linkky
Ron
Someday I'll build one too.
That´s great info thks Ron. Is it worth using a variac to test the heaters?
Could be useful if I want to get 6.3V out of the 12 or out of the 5V.
I thought it was much more important with the B+ voltage.
Any ideas for a home made Variac for a 275V supply?
I can´t afford to buy a variac here. They seem expensive.
?Olle: Did you test your B+ with the entire voltage on start up
Could be useful if I want to get 6.3V out of the 12 or out of the 5V.
I thought it was much more important with the B+ voltage.
Any ideas for a home made Variac for a 275V supply?
I can´t afford to buy a variac here. They seem expensive.
?Olle: Did you test your B+ with the entire voltage on start up
Yes I did! It's the way I usually do...Brit01 said:Olle
About the computer PSU: If you want to test the heaters, why don't you do it with your filament transformer?
By the way, it's a good idea to wire up and test the heaters before all other components!
Twin the heater wires, and put them away from the signal circuit. Corners are good!
I use to twin them with my drill machine
ollebolle said:
But why? Weren't you going to build Bas Hornemans aikido psu? It's a perfect psu for a Aikido!
Agreed! The 6x5 rectifier tube comes on slow so if the voltage spikes way out of line.....say more than 350V you can turn off the power before any damage occurs. Just wire up the DVM and have a finger on the power switch.
Having said that a Variac is a great safety device.
Sorry they are so expensive there Brit. FleaBay?
Ron
Brit01 said:That´s great info thks Ron. Is it worth using a variac to test the heaters?
Could be useful if I want to get 6.3V out of the 12 or out of the 5V.
I thought it was much more important with the B+ voltage.
Any ideas for a home made Variac for a 275V supply?
I can´t afford to buy a variac here. They seem expensive.
?Olle: Did you test your B+ with the entire voltage on start up
Brit,
Here is one on UKEbay, I don't know the brand but the price is right!
UK
Ebay variac
Ron
Good to know. I will do that.
Sorry what do you mean by Twin the heater wires?
Twist you mean?Yes i will use my new transformers and with Bas's psu. Just thought that I could use the pc power supply board if I need to test the heaters with DC and not AC.
Also it may have a good regulator on it that I could use in case I decide to use DC.
Sorry Ron I'm in Uruguay. We have a ripoffbay called mercadolibre.com.uy.
No cheap deals. It's not really the same. I buy loads of stuff from the UK, but all light stuff that my parents can send. A variac is not really an option.
Yes! A clean tip on your soldering iron is important!
I think I meant twist Twist all ac wires like this:
I think I meant twist
Twist all ac wires like this:An externally hosted image should be here but it was not working when we last tested it.
Did you use solid core for the heater cables? Easier to twist.
What diameter?
I managed to find the blown components on the pc power supply.
2 varisters.
241KD07
Totally burnt. These protected the other parts I guess.
Not sure if they are easy to get hold of here in Uruguay.
After some effort I managed to desolder them. Cleaned the joints very well with a fine wire brush, cleaned my iron tip (it's fairly new) and had to apply a lot of heat to get them lose.