Aleph-X builder's thread.

[lgreen]

Netlist! You are a genius! Good thing I sent you the pics after all huh?

As far as I can tell the schematic was correct. For the physical connections the left side was correct but the right side was wrong because I forgot that you have to flip the transistors around which switches the source and gate pins. Doh!

OK, so I've updated the pics, for those of you that can get to them they are-

Connection 1 option
Connection 2 option
Connection 3 option

Schematic (left side) (unchanged).

The links are the same so clicking on the prior post will bring up the corrected layouts.

Originally posted by BobEllis
OK - I just looked at the left sides, assuming that they would be the same. I did the same when LGreen shared the ideas with me privately before posting. Embarrassing mistake for a lawyer to assume rather than verify.

Don't feel bad Bob, its more embarrassing to be the lawyer who made the mistake in the 1st instance!

Anyway I hope these are right.

As Bob says, the connection2 and connection3 options are for placing 3 terminal screw headers onto the board where the transistors were meant to be, which is why the gate resistors on the board are shorted. I thought it might be easier to connect up this way.

[Netlist]

The schematic you sent me looks good.
Post it, you'll never know it can be improved by others.

/Hugo

[lgreen]

The schematic is the same one that is posted above (#1081) and in #1063.

[Netlist]

Oh...didn't know.

/Hugo

[lgreen]

Sinks mostly tapped, Boards mostly stuffed....making progress.

Update

CRC resistors (0.2 ohms) on bottom plate of chassis or main heatsinks.

[moe29]

don't you just love drilling and tapping?!!

looks great, nice work

[lgreen]

Originally posted by moe29
don't you just love drilling and tapping?!!

looks great, nice work

I find drilling and tapping to be really neat but I just don't like doing a lot of holes at once. I broke 1 tap already and had to punch it out with a metal scratch awl. At least that's what I think it is! Tools are not my thing. All those holes on the heatsinks and only 1 that is way far off and about 4 that don't go all the way through (they lined up on a fin).

[lgreen]

Does anyone know whether the case of the IXYS bridge module VBE 55-06N07 (data sheet here) is isolated or not isolated? Pic attached.

As you see in the pic, the bottom of the package is metal, I've mounted it to my case with thermal compound and it occurred to me that it may be live! I measured it with a DMM and found open circuits between all pins and the case (swapped DMM leads and results are also the same), did a diode test (again swapping leads, same result) and found no drop between any pin and the case.

Funny thing is that IXYS doesn't have any info on this and the data sheet indicates nothing.

Anyone know this package?

I hate to fire up the xformer without being sure.

note- I also posted this question in the krell thread, need a quick answer as this is holding me up....

[carpenter]

Hi,

What with my being a newbie, take what I say with caution.

I'd disconnect the DC power leads from the rectifier and then fire it up. Then, measure the case against the two DC output leads with your multimeter. I don't recall using mica with any rectifier.

John

[wuffwaff]

Hi,

the datasheets speaks of a ceramic base plate. This would mean that it is electrically isolated (as usuall with bridge rectifiers).


William