Auction find; LED Sign

I pickFull RGB displayed up three of these interesting full RGB display signs from a local government auction; and while I haven’t done a lot of picking apart just yet, it looks like it’s completely tied to proprietary software. The company that built it the internals appears to be an Australian company that’s no longer in business. It’s beautifully bright, all the LEDs seem to work, and it’s powered by a very impressive 40 amp 5 volt power supply.  

All sorts of IO.  Ethernet (no I haven’t hooked it up to the home network just yet), RS232 (there’s a 485 in/out not shown in this photo as well). Some custom peripheral port, and weirdly there’s an audio input that goes to the logic board, but it doesn’t contain any audio display; I’m guessing there’s some software based way of having it do sound triggered/modified displays.

There’s a main CPU board, that drives a secondary board, and then three identical LED driver boards. Anyway, this will be my next project, and if I don’t get anything else out of it other than a 1000 bright RGB LEDs and a 200W 5V power supply, I’m still ahead.


LED Driver
One of three LED driver boards
Main CPU
The whole contraption

Wow, I should post more

power supplyTime sure flies.  I haven’t posted here in a while, but I thought I’d upload a few pictures of the most recent hack around the bench.  Took my old Radio ‘Battery Eliminator’ (12V, 3A), and converted it into a constant voltage/constant current supply using a little module I got from China (link here)

Moved the transformer inside the power supply back to make a little more room, and added a supply line fuse (it had an output fuse already).  Once that was done, I hacked the front to make the new module fit and added a couple of binding posts, making sure of the 0.75″ spacing (unlike the last time I hacked something like this), and I think it turned out rather well. I may still add an internal fan if it gets too warm, but I don’t use enough current out of it for that to likely be a problem.



power meter

I had also heard that these things weren’t particularly accurate, so I was curious to see how close it really was.  I hooked up an LED bulb (supposedly 2W, but closer to 1), and the current showed 94mA and the meter (Yes, the BM235 from EEVBlog) shows 96.1mA so about 2.5% off, but that’s close enough for the stuff I do.  It will be nice to be able to limit current, and also to have a quick current display to glance over at, rather than having to hook up a meter when I want to read it.

Of course the picture also shows my 1970s vintage Weller W-TCP-L, which is still going strong 40 years on. I’ve bought new tips (mostly use a 700 small chisel – for PCB work, and an 800F larger chisel – for bigger work), and it’s a champ.

Now to get back to what I came downstairs to do, pack up a Tindie order.  THANKS GUYS for all the support.  I’m not getting rich selling on Tindie, but it’s still a thrill to get an email saying “you have a new order!”

Finished cleaning

The new parts drawers

I bought myself a birthday present, even more parts drawers. You can see the original ones (lower set on the left) as they’re a slightly different blue, but I decided what the hell, I’ll just buy the local distributor out of the last of their stock. There were a couple of casualties in shipping (mostly the really big drawers), but only had to toss one (and deal with cracks in one other).

After much sorting, labelling, divider gluing and generally going “what the heck should I call that”, I’ve emptied all my little flip top bins, and now have well over a 100 little drawers of awesomesauce (yes it’s a word, just added to the OED).

I’m sure I’m the only person that stresses about what kind of label (Avery 02209; removable) to use, or even what font (Source Code Pro, lower case). Have to say I’m glad I hunted for the right label. They’re the right size, and as they’re the removable style, easy to peel off if you make a mistake.

What does your parts cupboard look like?


Decided I would re-purpose some drawer units I had in the garage into the electronics storage. Quite a few things I own are too big for my existing method of flat storage boxes; especially some of the nuts/bolts/screws type items which I kept in the garage anyway.

Cleaning Storage Drawers

So, I relocated the drawer units in from the garage and gave them all a good wash. It’s amazing how dusty/cobwebby (is that a word?) it is in the garage. 20+ yr old labels needed cleaning off, but they seem to come off with some soaking. Some of the drawers I’ll continue to use for their original purpose (small nuts/bolts/screws/standoffs/grommits), but there are a few things that just don’t fit in my flat boxes very well (heatshrink, feet, stuff like that) that I’ll transition over.

These [Integrated Plastics Add-a-Drawer] really are the best drawer units I’ve ever come across, and I’m still kicking myself for having given away a bunch of them to the local college when I moved 12 years ago; oh well. Apparently Tenaquip still sell them even though the original company that made them is long gone; maybe I’ll buy another unit to add to what I have already, for now I’ll just keep an eye on Craigslist/Kijiji in case someone is selling some. If anyone does have any and they’re interesting in giving them up, give me a buzz…