Irfp044 for Aleph2?

[kilowattski]

I have decided to build an Aleph 2 before I tackle the Aleph X. I figured since it has been a long time since I have graduated college and have been selling test equipment since, so I figured I would shake the cobwebs out with the Aleph 2 or Aleph 4. My Zen IV was successful so I will take the next step and fully learn the Aleph. I have a load of IRFP044's left over from the Zen IV and both the Aleph 2 and Aleph 4 call for the IRFP244's. I would hate to flash a bunch of IRFP044's, so I ask the experts, can I use the IRFP044's in place of the IRFP244's? Don't laugh at me too hard.

 

[Andypairo]

Being the IRFP044 a 60V part I wouldn't use it with Aleph2 rails, which are higher than 40V.

Use at least a 100( better >150) volt type.

Cheers

Andrea

 

[MikeW]

build a 3

Build a 3 or 30 with +/- 25 volt rails. They are easier to carry.

 

[Nelson Pass]

Use the Aleph 2 grade sinking with 30 volt rails and bias them
even higher.

 

[kilowattski]

Nelson,

Thank you for the reply. Just so I have it straight, you are saying to build the aleph2 with 30 volt rails and irfp044's and bias the living daylights out of them? OBTW, thanks everyone for not laughing.

 

[GRollins]

(Ha, ha, ha...just kidding)
Sure.
Download the '044 spec sheet. Look for the SOA chart. Keep one eye on the chart and one on the bias. Use big heat sinks. Leave some margin--don't see how close to the line you can take it. Bias the bejabbers out of the little fellows. You won't get the full wattage of an Aleph 2, but you'll have a really smokin' Aleph 30.
Perhaps I shouldn't have phrased it that way...

Grey

 

[kilowattski]

Thank you Grey,

After getting an EE close to 30 years ago and using very little of it I have to relearn alot. Thanks for your help.

 

[GRollins]

In my case it was degrees in geology and psychology. Don't ask me questions on either field, 'cause I'd have to go look up the answers. As they say, if ya don't use it, ya lose it.

Grey

 

[Nelson Pass]

Just so I have it straight, you are saying to build the aleph2 with 30 volt rails and irfp044's and bias the living daylights out of them? OBTW, thanks everyone for not laughing.

That's what I would do.

 

[nobody special]

Download the '044 spec sheet. Look for the SOA chart. Keep one eye on the chart and one on the bias.

Damn your eyes!

Too late!