Hi Todd
One problem that's common to both the TO-220 parts and the potentiometers is that they're all RFE -- "removed from equipment" and as such don't have perfectly straight, clean leads. If that were the case, at least on the TO-220s, I could simply use a ZIF socket and move the connections when I wore out a set of 3 holes.
Similarly, I could wear out a plug-in breadboard, 3 holes at a time. If you've ever had a worn-out plug-in board, you know what a nightmare this becomes. I know how to fix them, but having learned how to fix them I prefer to build dead-bug style or make a PCB for my prototypes.
For this application, sockets really won't work because none of the leads are factory-new. Instead, I'm looking for a clamp-style technology because it'll be much more tolerant of messed-up leads. I'll probably have to get out the epoxy and little bits from the junk box and invent a clamp fixture.
I was kind of hoping to find somebody who'd done large-volume incoming test on components, and pick their brain a little, and maybe suggest a commercial fixture that'd save me several hours of inventing.
Incidentally, saving a few hours in NOT having to-re-invent a fixture, nor repair it every few dozen devices, will be a godsend for me. I'm not kidding about how many of these things I have.
Maybe I'll test the electronics I build with a socket, using the stick of 48 new LM7808s I have. Then I'll let everybody know how well that worked and how long it lasted...
73
Jim N6OTQ
One problem that's common to both the TO-220 parts and the potentiometers is that they're all RFE -- "removed from equipment" and as such don't have perfectly straight, clean leads. If that were the case, at least on the TO-220s, I could simply use a ZIF socket and move the connections when I wore out a set of 3 holes.
Similarly, I could wear out a plug-in breadboard, 3 holes at a time. If you've ever had a worn-out plug-in board, you know what a nightmare this becomes. I know how to fix them, but having learned how to fix them I prefer to build dead-bug style or make a PCB for my prototypes.
For this application, sockets really won't work because none of the leads are factory-new. Instead, I'm looking for a clamp-style technology because it'll be much more tolerant of messed-up leads. I'll probably have to get out the epoxy and little bits from the junk box and invent a clamp fixture.
I was kind of hoping to find somebody who'd done large-volume incoming test on components, and pick their brain a little, and maybe suggest a commercial fixture that'd save me several hours of inventing.
Incidentally, saving a few hours in NOT having to-re-invent a fixture, nor repair it every few dozen devices, will be a godsend for me. I'm not kidding about how many of these things I have.
Maybe I'll test the electronics I build with a socket, using the stick of 48 new LM7808s I have. Then I'll let everybody know how well that worked and how long it lasted...
73
Jim N6OTQ
On Wednesday, October 30, 2013 1:14 PM, Todd F. Carney / K7TFC <k7tfc@arrl.net> wrote:
On Wed, Oct 30, 2013 at 10:27 AM, Jim <n6otq@yahoo.com> wrote:
Did I leave out the part where I said that I had dozens, perhaps hundreds, of these devices and I don't want to rebuild a test jig every time I want to use a device?
And did I also leave out the part where if I'm going to be testing dozens, perhaps hundreds, of these devices at a time, that I don't want to squeeze three separate alligator clips for every device, and replace the clips when they invariably go bad after a hundred squeezes?
Jim,No, you didn't leave those parts out, and neither did you omit "I'm willing to discuss and I welcome suggestions."Since the leads of TO-222 devices are spaced 0.10" apart, you can rely on a piece of an IC socket for your DUT receptacle. You could also use a small plug-in breadboard--just a few bucks--and set up your test circuit on that. All the sockets on those are spaced 0.10" as well. I have a few circuits I've "breadboarded" but then leave intact for later use.73,Todd------------------------------------------------------------------------------------K7TFC / Medford, Oregon, USA / CN82ni / UTC-7 (PDT)------------------------------------------------------------------------------------
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