ROOPHLOCHING WITH THE ROOS Jeeze this would look strange from a distance. It's a dark damp night with no moon in the sky, the only sound is distant frogs chirping from every angle, and here at the side of an empty paddock there's a square block of light from a twenty year old Thinkpad illuminating a figure of a man sitting on a surprisingly not wet rock. The local kangaroos do regularly come into this paddock in the evenings so I may be ROOPHLOCHing with the roos, but then again I could be ROOPHLOCHing with a elephant for all I'd know in this dark. In fact the deep thuds of a roo bounding about probably wouldn't be that welcome when I can't see what it's coming from. Anyway this is a bit of a last minute entry because I wanted to test out [first mozzie] an optical communications system. Long story short, I didn't manage to get it together in time. I did buy a photodiode ages ago, and a few days ago I finally got around to building an amplifier and comparator circuit for it, which could then be interfaced to a PC serial port. The amp circuit is a pretty simple current to voltage converter application, but conventionally it requires a split supply. However I found an example circuit from TI for a single-supply design, and although I didn't have the op-amp specified it seemed pretty clear than any FET-input op-amp should do. Three hours, and two models of substitute FET-input op-amps, later I finally concluded that there was more to the circuit than it seemed. I still don't know why it didn't work to be honest, but [first moth to the screen] actually two battery packs for a split-supply circuit isn't that hard to accomodate and with that everything started working as expected. But I was only getting about 1m range testing with the spare panel of 26 red LEDs that I had handy, so I then went hunting through all the spare lenses from old projectors and camera junk, and eventually found a combination of what I think is a 8mm movie camera telephoto lens and a projector lens which seems to get me at least three meters (and as far as I can get away from my workbench). Trouble is, at that point I didn't feel like doing an all-nighter to try and rig up the serial interfaces (also for the LED transmitter), and fix the lenses in some positionable way. The days since have been pretty busy, so it wasn't worth it for the sake of a self-imposed restriction on a fairly irrelevent challenge. Anyway, optical communications aside, it's been a crazy time in Aus lately, and particularly last week. The lockdowns in Melbourne spread to my area (actually I was on the border, at the wrong side of the road), though thankfully ended last week. In Melbourne there were angry mobs confronting police, and it's interesting to compare media coverage of that with eg. the protests in Hong Kong, or even the US. Here lots of shots of mobs waving banners, but not much of the riot squad swarming them and shooting things as was on apparantly shown on social media. I think the protests were stupid, but like with the media's coverage of Trump evident bias actually makes me feel more defenceive of them. [shutdown, batter swap, restart] OK I'm now on my second battery (I got two about seven years ago and by now they both only last about an hour), at least that got rid of the moth. Hey, an hour, and I started this after 11:00PM... Bugger! 12:00AM exactly, I missed the deadline. Oh well, it's probably still yesterday whereever it is in Europe that SolderPunk lives, us Aussies have the luxury of coming to you from the future. I'll skip commentary on the nuclear sub deal, and as a nuke nut that's not easy, and go onto [now that's a weird looking bug...] my first earthquake experience before I leave you. The state of Victoria has it's strongest recorded earthquake, around magnitude six which is apparantly the same as the Christchurch earthquake in NZ, but this one was out in the mountains about 100Km from Melbourne and a few more 100Km from me. Still, I was busy trying to solder together circuit boards and actually I thought I'd was going giddy on the solder fumes or something except the curtains seemed to be moving as well. I never realised the it's almost as hard to tell what's going on in an earthquake in real life as it looks in on TV - the only cues are equally explainable as draughts in my house, except that there didn't seem to be much wind (the childhood education that we don't get earthquakes in Austrlia doesn't help either of course - is anything they taught me at school genuinely true?). In fact in the strong winds I get out here I would have easily believed it was the house rocking against the force of a gust on a blowy day. Anyway I got up and went outside, partly to see whether I could walk or was about to pass out on the floor, and partly to see whether the apocalypse was neigh. By the time I got out it was all over and, after checking that the house wasn't collapsing and there weren't any mushroom clouds on the horizon (nuke nut, like I said) I went back in and called my father. He'd been outside and assured me he hadn't felt a thing, so after that I was sure I was going crazy. But he did call back after other people had apprantly asked him whether he'd felt the quake, and there was plenty on the news that night. Well it turns out the open surrounds make me open up, even if I can't see them, and I've babbled on plenty. I'll try to upload this now over boring old mobile broadband, not that it's always a sure thing either. Then I'll try to make my way back to the house without getting tagled up in old fencing wire again. It didn't start raining at least, so that's nice. In fact the nights have been so cold for most of this month that I wouldn't have had much opportunity to do my optical comms experiment anyway (assuming it doesn't work very well in daylight). Goodbye from me and the roos (maybe). - The Free Thinker. Oh, the LED on this mobile broadband modem is REALLY BRIGHT! Rats, the rules say by midnight local time, oh well. Thursday is the only day of the week when there's actually some decent stuff on TV so what hope did I have? :)