JM-SST, External Pot and Dual FETs

[JimmyM]

I just finished building a couple of these for another CPFer but thought a post and a pic would be nice. It has a provision for an external pot for adjustment. The Dual FET board has "buss bars" of 10ga Solid copper wire hammered flat for high current as well at good thermal distribution. I'm not sure If I'll add a heatsink with thermal epoxy. These are intended for use in a Larry14K type light. I know there are L14Ks running the single FET, but this is by special request. Plus, this one should never have any overheating issues. Ever. The copper bar extensions on the right can be soldered to or be drilled for ring terminals.

 

[Mr Happy]

Nice looking work indeed. Just a little suggestion -- it greatly enhances such pictures if a ruler can be placed alongside the items to provide a sense of scale.

What kind of tools do you use to construct those boards? Make your own PCBs or get them made professionally? A basic iron, a temperature controlled solder station, or a full professional rework station? Magnifying loupe, basic magnifier, or binocular microscope?

 

[JimmyM]

Nice looking work indeed. Just a little suggestion -- it greatly enhances such pictures if a ruler can be placed alongside the items to provide a sense of scale.

What kind of tools do you use to construct those boards? Make your own PCBs or get them made professionally? A basic iron, a temperature controlled solder station, or a full professional rework station? Magnifying loupe, basic magnifier, or binocular microscope?

Good tip on the ruler. Not everyone knows how big some of these parts are. Also, one MOSFET can look exactly like another if it's enlarged.
It measures ~1" x 1.5". The Jm-SST board is normally round and 30mm in diameter.
For these external MOSFET boards, I just used a dremel to cut a line between the copper areas I wanted to keep. The JM-SST in the upper part of the picture I etched on a mosaic with another 27 boards. After etching, I cut them apart on my band saw. For etching I use Ferric Chloride. I'll be using that up until I run out. Then I'll use some Sodium Persulfate that I bought recently. For soldering I have a Weller WES51.

 

[JimmyM]

See the wiring diagram below.