troubleshooting DAC 19M008 power supply

[sabre504]

Re: troubleshooting DAC 19M008 power supply

That would explain the no 5v i dont suppose you have another you can replace it with

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

That would explain the no 5v i dont suppose you have another you can replace it with

no, do you know of a place here in the USA that has this fuse?

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

That would explain the no 5v i dont suppose you have another you can replace it with

found a few on Ebay for $2 to $5

I'll give it a try and post the results. Thanks much for the help so far.

TTFN!

[sabre504]

Re: troubleshooting DAC 19M008 power supply

There is a company on ebay called coreweave in Kaukauna, Wisconsin

They do a kit for this board that includes the fuse all the caps you need and new mosfets item 220620219872

Or just do a search DAC-19M008 on there and it will come up with several
Checkout this site in the sales bit they may have a kit or could supply the parts you need

You can use the list of parts to buy stuff individually .

Whatever you do i would change the caps that you have not changed yet that way they are all done and you wont have to open it up again in a few months and do some more .

The fuse is a 4amp smd fuse

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

That's who the Ebay listing was. It's $1.50 and free shipping

There is a company on ebay called coreweave in Kaukauna, Wisconsin

They do a kit for this board that includes the fuse all the caps you need and new mosfets item 220620219872

Or just do a search DAC-19M008 on there and it will come up with several
Checkout this site in the sales bit they may have a kit or could supply the parts you need

You can use the list of parts to buy stuff individually .

Whatever you do i would change the caps that you have not changed yet that way they are all done and you wont have to open it up again in a few months and do some more .

The fuse is a 4amp smd fuse

[sabre504]

Re: troubleshooting DAC 19M008 power supply

Ok good well let us know how you get on
good luck

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

How sensitive is this fuse to the heat, is there a chance I could fry it while installing it?

[sabre504]

Re: troubleshooting DAC 19M008 power supply

Just solder new one on top of the old one that will cut down the amount of time and heat you put into it

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

Just solder new one on top of the old one that will cut down the amount of time and heat you put into it

Excellent idea. Thanks

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

Installed new fuse, tested before applying power, tested dead short. After applying power fuse tests at 210 ohms. Still no green light. What could have caused the new fuse to fail?

[budm]

Re: troubleshooting DAC 19M008 power supply

You need to check the two MOSFET'S that drive the inverter transformers for shorts.

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

tested pin to pin on all pins, no shorts other than pins 5,6,7 and 8 on both MOSFETs, since they are all grounded

[budm]

Re: troubleshooting DAC 19M008 power supply

tested pin to pin on all pins, no shorts other than pins 5,6,7 and 8 on both MOSFETs, since they are all grounded

Please see the diagram and retest the MOSFETs, the circuit is setup as a bridge drive, 5,6,7 and 8 should never be at ground, if they are, they are shorted, only pin 1 is grounded.

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

sorry, 5,6,7,8 all connected together but not grounded

where can I find the diagram?

[budm]

Re: troubleshooting DAC 19M008 power supply

post #3

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

both MOSFETs: pins 1 to 2 measures 29 M Ohm, 1 to 3 is 7 M Ohm, 2 to 3 is 35 M Ohm, 3 to 4 and 3 to 5 is 30 M Ohm, everything else is open (except for 5,6,7,8)

[budm]

Re: troubleshooting DAC 19M008 power supply

How about Source (1) and Drain (5/6/7/8)?
By the way, what resistance do you get at the either end of the fuse F102 and Ground? You still have short circuits in the main board.

[budm]

Re: troubleshooting DAC 19M008 power supply

VA1912WB service manual

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

pins 1 to 5,6,7,8 is open

from the outboard end of the fuse to ground is 300 k Ohm, inboard side is 2 k Ohm

[mikeh1]

Re: troubleshooting DAC 19M008 power supply

VA1912WB service manual

already got it, it tells me to change the power board