Trying to build a car battery desulfator..need help with part info

[nobb]

Hello.

I am trying to build a battery desulfator to revive a car battery that I found for free. Here is the pdf with the schematics:
http://www.alton-moore.net/graphics/desulfator.pdf
The schematics look pretty simple. Building the desulfator is the easy part. The hard part is finding the parts (hopefully locally). The most complicated components are the LM555CN (which I know where to buy) and the IRF9Z34 (I think I know where to buy).

The IRF9Z34 is a P channel MOSFET. Is there any reason why I cant use another model of P channel MOSFET to save some money? I have a bunch of old dead circuit boards and computer power supplies where I ususally harvest my parts.

Also, the plans call for a GI826CT fast recovery diode >6A, 100V. This is the part I am having trouble finding. What is a fast recovery diode? I cant find this particular model diode in the local store stock website. I was wondering maybe someone could tell me what these fast recovery diodes look like. Maybe I can harvest one from my dead circuit boards/pc power supplies?

I am also thinking about just using EDTA to desulfate the battery, although I would prefer the pulse desulfating method so as to not waste plate material. I am pretty comfortable with pouring out acids and stuff like that. Would the EDTA or pulse desulfating method yield better results? I am not sure where to post this, but you guys seem really knowledgeable.

Advice would be great. thanks.

 

[Born2bwire]

Originally posted by: nobb
The IRF9Z34 is a P channel MOSFET. Is there any reason why I cant use another model of P channel MOSFET to save some money? I have a bunch of old dead circuit boards and computer power supplies where I ususally harvest my parts.

Also, the plans call for a GI826CT fast recovery diode >6A, 100V. This is the part I am having trouble finding. What is a fast recovery diode? I cant find this particular model diode in the local store stock website.

That's something you'll have to find out. You need to look up the datasheets and find a replacement part that can meet or exceed the parts you want to replace. I certainly would not get them off of dead circuit boards unless you can find the datasheets for the parts your stripping. Personally, I would just buy the parts referenced in the schematics. Less work and you won't have to go through the trouble of verifying the proper replacement parts and figuring out the pin layouts to match the schematic.

Here's the GI82X series.
Text

 

[PottedMeat]

Originally posted by: Born2bwire

Originally posted by: nobb
The IRF9Z34 is a P channel MOSFET. Is there any reason why I cant use another model of P channel MOSFET to save some money? I have a bunch of old dead circuit boards and computer power supplies where I ususally harvest my parts.

Also, the plans call for a GI826CT fast recovery diode >6A, 100V. This is the part I am having trouble finding. What is a fast recovery diode? I cant find this particular model diode in the local store stock website.

That's something you'll have to find out. You need to look up the datasheets and find a replacement part that can meet or exceed the parts you want to replace. I certainly would not get them off of dead circuit boards unless you can find the datasheets for the parts your stripping. Personally, I would just buy the parts referenced in the schematics. Less work and you won't have to go through the trouble of verifying the proper replacement parts and figuring out the pin layouts to match the schematic.

Here's the GI82X series.
Text

Heh yeah, just follow the given parts list. I would just use the suggested Digikey stuff, the total cost for the unit appears to be ~$25 ( $20 for the parts and probably $5.00 for USPS Priority Mail ). It's a real hassle to swap parts if you aren't sure of what you're doing - as said matching device parameters and even the pinouts. As to the diode, use the datasheet and use the Digikey search to find a similar one.

 

[Born2bwire]

Originally posted by: PottedMeat

Originally posted by: Born2bwire

Originally posted by: nobb
The IRF9Z34 is a P channel MOSFET. Is there any reason why I cant use another model of P channel MOSFET to save some money? I have a bunch of old dead circuit boards and computer power supplies where I ususally harvest my parts.

Also, the plans call for a GI826CT fast recovery diode >6A, 100V. This is the part I am having trouble finding. What is a fast recovery diode? I cant find this particular model diode in the local store stock website.

That's something you'll have to find out. You need to look up the datasheets and find a replacement part that can meet or exceed the parts you want to replace. I certainly would not get them off of dead circuit boards unless you can find the datasheets for the parts your stripping. Personally, I would just buy the parts referenced in the schematics. Less work and you won't have to go through the trouble of verifying the proper replacement parts and figuring out the pin layouts to match the schematic.

Here's the GI82X series.
Text

Heh yeah, just follow the given parts list. I would just use the suggested Digikey stuff, the total cost for the unit appears to be ~$25 ( $20 for the parts and probably $5.00 for USPS Priority Mail ). It's a real hassle to swap parts if you aren't sure of what you're doing - as said matching device parameters and even the pinouts. As to the diode, use the datasheet and use the Digikey search to find a similar one.

I checked and Digikey carries them. On the search list they say that you can order single units for around 71 cents a pop but the window that pulls up with the part details asks you to call to place an order.