Hey guys, I'm having a bit of a problem here. I bought a Soarer's Converter for XT keyboards from Orihalcon on eBay a while ago, used it happily for some time, only to have it develop an intermittent fault. He had me send it back and sent me a new one. Now that one has developed a fault too, at first it was intermittent too, but last week it just up and quit on me. I decided that, as I had already received a second one and that it had been some time, I would tackle this one myself, especially as my soldering skills have improved greatly and I have a lot more tools for electronics work.
I proceeded with disassembly and discovered that the circuit board inside the USB plug was potted in hot snot (da bigger da gob, da better da job, amIright? ...) which hadn't bonded to the board or components, or even the rubber shell, only the wires. I cut everything back and proceeded to solder up the USB and DIN-5 connections now inside an enclosure box with a panel-mount DIN-5 and a USB cable with a gland, salvaged from some other thing long ago. Unfortunately, when I was doing something, I managed to knock off a tiny little surface-mount component about 1/4 the size of a grain of rice. Aided by a bright LED torch, I finally found the goddamn thing (on a filthy cement floor... fun!) and was able to put it back on the board, thanks to my needle tweezers. Testing it with a meter showed it seemed to be a capacitor, as with the probes in one orientation the meter counted upwards and in the other downwards (in Ohms mode, beautiful old HP 3455a). I put it back in what I thought was the correct orientation and tried the unit. Plugging it into a laptop for testing (Dell Precision M60 portable workstation) I got an error from Windows: "Power Surge on Hub Port". I checked all my work, found some little bits of wire from the USB side that may have been making contact with one-another and trimmed them back. Same problem. I swapped around the orientation of the mystery surface-mount device, still the same error. What's up here???