Oct 31 2011

Roll Indie Fiftee Reap Air

Just so you know, I’ve been nerding out pretty hard this past week.

Last Monday, I picked up a very used Roland D-50 keyboard at the pawn shop. Although it was manufactured in 1987, it still output audio and the MIDI still works, but the poor thing has problems (I should’ve talked them down on price, but even still I got a decent deal). All of the keys on the fingerboard worked, but a few of the keys had screwed-up velocity sensitivity. The pitch bend was busted. And some of the panel buttons either don’t work or require a heavy push to get them to work. This poor piece of gear needed some serious TLC.

Knowing what I was up against, I made the due diligence to get some required tools to do the cleanup and minor repairs. Got some paint brushes for dusting, a wire brush to scrape any rust, some 91% rubbing alcohol (because 70% has too much water), and a can of electronic contact cleaner.

Within an evening I had it taken apart. The damned thing had spiderwebs and cat hair in it. No wonder it half worked. Last owner didn’t give a shit, and it shows. I got most of the crap out of the case in short time, but it took another evening to get the fingerboard completely disassembled, and I mean completely, like down to the frame. Pulled the keys off and soaked them in soapy water; they were as nasty as the bottom of a computer mouse.

It took a few evenings, but I got both circuit boards under the keys cleaned, got the rubber contacts wiped down, all the dust and “water damage” (to doctor the truth) are cleaned up. I found proof that the keyboard has been worked on before by someone who didn’t have the smarts or the tools to do the reworks correctly, and that probably accounts for one of the keys reporting full velocity on each press. I redid the rework; hopefully that fixes that.

Yesterday, I decided that I was tired of having sub-par tools to do electronics work. After having the pleasure of working with professional soldering equipment at work, my piss-poor Radio Shack iron just won’t do anymore, so I went to the electronics store and got a good Weller soldering station, a handful of different tips, a bottle of solder flux, a dispenser, and a cheap multimeter to replace the piece-of-shit I’ve had to use for the past 25 years. Nerding hard core.

This afternoon, I pulled the entire unit apart, taking the boards and cable assemblies off of the master frame. Took them to the balcony for dusting and a heavy session with the contact cleaner. Afterwards, more of the panel buttons went non-functional, so I spent part of this evening tracking down replacement parts. I desoldered and removed one of the switches, and I’ll take it to work tomorrow to get its exact dimensions with some proper measuring tools. If it matches the replacement switches I’ve found so far, I’ll be placing an order for an entire panel’s worth of buttons.

This is all very exciting!

Hopefully by next week’s end, I’ll have a fully-functional Roland D-50, refurbished and ready to go. And then the hard part will begin: writing music. D’oh!


Feb 1 2010

Swap-o-Rama (¡UUID Es Me Llamo!)

(Just for the sake of remembering my own damn self — and maybe helping someone else.)

Earlier, I attempted to hibernate my desktop. Never done it in the 15 months I’ve had Ubuntu 8.04 LTS on here, so I figured “Hell, why not?” I hit the dropdown, and the system commenced its hibernating shutdown action. But it neither shut off nor came back to life. I ssh’d into it to discover via the system logfile that the hibernate was halfway through its operations when the power daemon discovered “Oh Hell! There’s no resume device on this machine!” at which point it ceased and attempted to raise the machine from the dead.

After manually power-cycling the system, I did some digging. Turns out the UUID of the swap/resume partition had been changed somewhere along the way, so both /etc/fstab and /etc/initramfs-tools/conf.d/resume were stuck with the old UUID from way back when the system was installed. That UUID no longer exists.

I’m not sure what caused it to change; such an idea is disturbing, considering this is supposed to be the super-stable, LTS build of Ubuntu. The UUID of the swap partition is usually set with the mkswap -U command, and can be set on an ext2/ext3 partition with the tune2fs command. But anything can go wrong.

So. How to make fix? A quick check with sudo blkid will list the block devices on the system:

oldman@Deskie:~$ sudo blkid
/dev/sda1: UUID="c97b2e80-a5b2-4371-a60e-126a8d1402a5" TYPE="ext3"
/dev/sda5: TYPE="swap" UUID="f3a3cd16-f0c8-40a1-8a7d-578c57296c6b"
/dev/sda6: UUID="775a56e3-0244-453f-8d8a-fd1eb42a82f6" /
SEC_TYPE="ext2" TYPE="ext3"

The swap partition has the UUID f3a3cd16-f0c8-40a1-8a7d-578c57296c6b and is the device /dev/sda5. Copy and paste the UUID into the fstab and resume config files to replace the UUID that was there. Execute sudo swapon -a to mount your swap partition, and you should be golden. Verify with free -m to check for a nonzero swap size.

oldman@Deskie:~$ free -m
             total       used       free     shared    buffers     cached
Mem:          3962       1784       2178          0        154        660
-/+ buffers/cache:        969       2993
Swap:        11601          0      11601

The value 11601 tells me I’m gettin’ my swap on. Aw yeah.