I recently purchased a Hakko FX-951 for home soldering. I was considering the FM-203 in case I ever wanted SMD tweezers, but the cost difference just didn’t add up. But, I knew that the Hakko FX-888D supported a SMD tweezer upgrade for less than $200 in case I ever needed them. But, I didn’t need the whole station, and the cost of the whole thing ($100 or so). To eBay I went, and found a “as-is” base for less than $40. It was missing the power cable, but showed to power up, and showing the “S-E” error. But it also didn’t have an iron plugged in, so that error makes sense (“S-E” is sensor error, claiming it can’t see the temperature of the iron)!
I have an ancient Dell 1800FP monitor at work that is used for a print release station (users swipe their cards, select their print job, and print it). This monitor runs 24/7, and has probably been running for next to 2 years pretty much solid. The other day, we had a power outage in the middle of the night, and when we came in the next morning and tried to turn the monitor on, it wouldn’t turn on (nothing). Knowing no other option than to try to fix it, I opened it up, and checked the voltage rails (12V and 5V). Both were pulsing on and off about once a second, and the power supply could be heard “ticking”.
I took the unit home (where I have a better setup for soldering/repair) and found several dry/cracked solder joints. Fluxing and reflowing those, however, didn’t fix the issue. Checking the main output caps all showed good as well (ESR all 0.0ohms on my blue meter). Thinking about it some more (what it was doing), it SOUNDED like it was basically starting up over and over again. So I checked the control chip, ICE2AS01 (this seems to be the primary failure on these units), IC901, and it looked fine (no short between ground and VCC). But then I checked its decoupling cap (C907, 47uF 50v): 27ohms ESR. Huh. The decoupling cap (C924, 33uF 25V) for the opto-isolator showed 4ohms ESR. I pulled both, and checked them again (with my DER DE-5000). C924 checked out relatively okay… 4ohms, 30uF (certainly a bit high on the ESR, but the capacitance was within spec). C907, however, was WAY off. ESR measured at 28ohms, and capacitance at 8uF. That’s more resistor than capacitor at this point. Digging through my old boards, I found another monitor supply board that had an exact replacement for C907 (47uF, 50v), and a close replacement for C924 (39uF, 35V). Both fit, and both measured close to 0.1ESR. MUCH better. I popped both in, soldered, and fired the unit up. No clicking, and solid 12V and 5V rails.
Yay, job done. So, while the power outage may not have helped, I’m guessing the unit was probably in this state for a while, and the fact that it was power cycled was the issue. Once that ICE2AS01 is up and running, that decoupling cap probably doesn’t overly matter. But on startup, it’s needed, and there just wasn’t the capacitance there to actually get the IC fired up.
Anyway, this is obviously another failure mode of these old units. And remember, just because there is no sign of bulging for venting doesn’t mean a cap isn’t bad. Just means it may have not failed quite so catastrophically as to vent.
Ever since my first CobaltFlux control box died, I’ve wanted to have a plan in place for a replacement should the current one die. Sadly, CF is out of business, so options are rather limited. But, the internet is a resourceful place, so I was able to quickly find a place to find plans for making a replacement.
It involves buying a generic USB to game stick adapter, and then soldering on the connections from a DB-25 (VGA) connector. In this case, I bought two of these. I removed most of the connectors, and just soldered wires directly to the pads for each “direction”. I then used a Hammond 1591BBU (blue) project box. Cutting a hole for the DB-25 connector is a pain in the but since it’s not square, but it turned out okay. I used a “dremel” cutting bit for my Proxxon to cut the hole just big enough to pressfit the DB25 connector, and cut a relief for the USB cable, and holes for the top “Start” and “Select” buttons. Mounting the board in the box was just a little hot glue on the bottom of the board.
Total cost for the parts were about $20. The soldering is simple, it’s mainly just doing the drilling on the enclosure. Total build time was about an hour, including testing. It’s a very easy build, and it thankfully works. =)
Good luck if you build one. I think I’ll build at least one more as a spare. This one described here was for a friend. =)