Dan's Data letters #103
Publication date: 8 May 2004.Last modified 03-Dec-2011.
Digital slides
A friend has asked me to find a piece of equipment to convert regular film slides to some digital format, eventually to be put onto DVDs. This friend has close to 10,000 slides, so this is a long project. I seem to recall a product that would allow you to drop in a slide and essentially scan the slide into a PC.
Do you know where I might find one of these? Do they make them with a drum or auto-loader, considering the size of the job?
Randy
Answer:
Yes, you can buy dedicated slide scanners. I think all of the big scanner companies make slide scanners; you
can buy them from regular computer stores (who probably don't have any in stock, but could certainly order one in).
Photo stores have them as well, but probably only with the legendary Photo Store Mark-Up.
The problem here is that slide scanners, even those with "auto feeders", are not a good way to chew through thousands of slides. You can do it, but there's no simple dump-'em-all-in-the-hopper-and-walk-away way to make it happen. It'll take a long time, and a lot of shuffling of slides by a hapless human. This is why professional imaging bureaux commonly charge something in the order of $US1 per slide to do this.
Once you've looked up commercial bulk scanning rates and gotten good and frightened, it's clear that dropping a few thousand dollars on a high end scanner is cheap, in comparison, provided you don't value your time like a corporate lawyer.
It's possible to get excellent scans of slides from a high end focus-controlled flatbed scanner, which has the further advantage that you can scan a bunch of slides at once - and the scanner software ought to be able to automatically clip out all of the images for you and save them separately.
Pro scanners (slide and flatbed) are also built for throughput - the images they make are pretty much perfect right out of the scanner. You can get results very nearly as good from all kinds of cheap consumer scanners (focus permitting) if you're willing to put in a few minutes of post-processing time for each image - but 10,000 slides worth of five minute tweaks adds up to more than a hundred extremely tedious eight hour days. I'm figuring your friend ain't that committed.
So, an expensive flatbed it is. Drum scanner even better (that's what an expensive bureau ought to be using, if they're worth what they're charging), but buying a drum scanner will also cost you far more than having a bureau do the scans.
You can rent high end scanners - lots of pro photograpers rent fancy gear when and as they need it - and various photo specialist shops could probably set you up. The most economical option would, therefore, probably be to rent a super-flatbed for the big job and burn through the whole task in a few days, then buy a quality dedicated slide scanner if you're going to need to scan more manageable numbers of slides per day in the future.
Here's an excellent page about this, including some product suggestions.
Trip-o-vision
I have an old Cicero monitor (actually a Hansol 910a) whose cable has a kink in it next to the connector on the PC end. When I unbend it the screen goes sort of bluish all over. Is it possible that if something shorts out that it will damge my videocard or the monitor's electronics?
I know how to not burn myself with a soldering iron, so I was also wondering if it would be a good idea to remove the original, permantly connected cable from the monitor, install a female VGA connector on the back instead, and get a double male cable that can be removed for transportation. The "ferrite shielding lug thingy" at the end of the existing cable is too close to the VGA connector to make just replacing it an easy job.
James
Answer:
If the screen's turning greenish-blue then you're missing the red channel; if it's pure blue then you're missing red
and green. These are classic fractured-wire-in-the-cable symptoms, of course. Such a problem is safe enough;
bent or loose pins in a VGA plug can mangle or get stuck in a socket, which will in turn mangle other plugs (the dreaded
"hardware virus"), but electrical glitches in the cable should, at worst, just stop the monitor from working.
Yes, you can fix the problem yourself, if you're up to it - deem usual warning about CRT monitor high voltage here. Depending on where the break is in the current cable, you could also just peel the insulation off it a few inches out of the monitor, snip and trace wires one by one, and put an HD15 connector there suitable for use with your cable.
Find the standard HD15 pinout, in case you need it, here.
Low-performance computing
My router recently kicked the bucket (it likes to randomly drop connections). I decided to replace it with an old computer we had sitting around. Throw two NICs in it, unplug the hard drive and throw in a floppy with a copy of Coyote Linux on it... tada, instant Web-configurable router.
Except, there's one thing wrong with it. The K6-2 processor has a nasty heatsink fan on it, and the bearing's going, making it extremely irritating. So, I pop it off and discover that Socket A heatsinks also fit on the ol' Socket 7, so I put the spare HSF from a Athlon XP 2100+ I had sitting in a drawer. Works great! Except, now, guess what? This fan bearing's going.
Now, what I'm wondering is if I can just disconnect the heatsink fan and let it live in happiness without baking itself to death. The CPU isn't being used heavily, considering Coyote will run on a 386 provided you tweak the distro to include math coprocessor emulation. I did my best to underclock the CPU, dropping FSB to 66 and the multiplier to 3, so I now have a K6-2 200.
The K6-2 400 is rated at a maximum dissipation of 25 watts while running at full speed, and the Athlon XP the HSF comes from is rated at nearly three times that! The heatsink doesn't feel hot to the touch even after being on for 24 hours straight, but I have no real way of telling temperature because the crummy Biostar M5ALC has no temperature sensor I can get at.
Will I bake my poor little K6-2 if I disconnect the fan? If so, are there any other options you can think of?
Erik
Answer:
Yes, you might be able to get away with running the thing without a fan, but I don't recommend it. If the heat sink
really doesn't get hot (and if it's not just because it's got a lousy thermal connection to the processor...) then
it might be OK - emphasis on the "might".
Assuming the heat sink you've got is made for 60mm fans, I suggest you get an 80-to-60mm fan reducer (or knock one together out of cardboard...) and stick a nice slow low power 80mm case fan on the end of it. That ought to keep air moving through the heat sink more than fast enough, and last for many years.
There are various other similar solutions that people have bodged up in situations like this - 80mm fans Blu-Tacked to the motherboard on either side of the heat sink for throughflow ventilation, or wire brackets holding whatever spare fans were sitting in the bits box - and with a pretty cool processor like yours, all of them are likely to work. You just want some kind of fan on or next to the heat sink, or no fan on it, but very high air flow through the computer case.
Invincible amplifiers
I've had this bookmarked for a while, with every intention of building one.
Then (a long time later) I came across this discussion, and had a nice little tete-a-tete with a guy named HardCase who makes CMoys.
During the course of all this, it occurred to me that some type of non-conductive filler would solve a lot of issues involving durability.
zeBrewDog
Answer:
You're talking about "potting"; covering an electronic device with something like epoxy, often to make it tougher
and sometimes just to stop people from seeing that their $500 car computer contains $5 worth of parts.
Neutral-cure silicone sealant is a quite good potting compound (NOT the vinegar-smelling acid-cure type); hot melt glue can work well, too, and many people also like "Shoe Goo"-type universal adhesive.
Something as simple as a CMoy amp, though, isn't likely to be made a great deal tougher by turning it into a solid block. You're welcome to do so - it's only a bad idea if there are power components that need significant cooling, which isn't the case here - but a straight CMoy amp will probably work fine for you. The tiny circuit board can be held onto the inside of a mint tin with a blob of glue; then, you just have to stop the battery from flopping around and hitting things. A bit of glue to keep the big electrolytic capacitors from vibrating should be more than enough extra armour.
Sagging cells
I have tried to find out how many times I am supposed to be able to recharge my Monster Powers (I use four AA size ones in my digital camera). I also have a Digital Concepts CH-3975 NiMH/NiCd charger that came with another set of four AAs. It seems to me that they aren't lasting as long now.
Jana
Answer:
Do you mean Monster PowerCells, the
Monster Cable-branded rechargeables?
They're just NiMH cells like any other, so they have the same basic characteristics - depending on the charger, you should be able to get several hundred full charges out of them before their capacity decays far enough to be a problem. Hard charging will kill batteries faster, and different batteries are of different quality, but I see no reason to expect the Monster ones to be any worse than other brand-name NiMH cells of similar capacity.
Your impression that your batteries aren't lasting as long is probably correct. Rechargeables wear out, but there's no clear point at which you can say they're dead. Just buy new ones when the old ones get too tired to be useful.
I'm pleased to note that Monster Cable are continuing their fine history of talking complete crap half the time on their battery FAQ page. That page verges dangerously close to not even being wrong. The longer I look at it, the more it looks like something written by a stoned work experience kid.
Their description of memory effect, in particular, is slightly garbled (the whole page seems to have been written by someone with a poor grasp of English, and of battery technology), but what information can be gleaned from it is completely wrong.
I'm Google hit #1 for "memory effect" at the moment, so I must be right.
They also say that their rechargeables will work in remote controls. Well, sure, they will, but all rechargeables are a lousy choice for remote controls; rechargeables have high self-discharge, which means they'll flatten themselves when left for months on end. The very low current draw of all but the most enormous after-market remotes means there's no reason at all not to use alkalines, or plain cheap carbon-zinc cells (which are usually what's supplied with the remote, and which, as you've probably noticed, often last for years).
Also, contrary to what Monster say, no batteries are "made of" nickel metal hydride. NiMH is a kind of battery chemistry; you can read more about it here. A solid block of nickel metal hydride is not a battery.
And rechargeable alkalines must not be completely discharged before charging again. Actually, that's the worst thing you can do to them. They like being topped up. Read more about them here.
Monster's "What is mAh" answer is basically correct, but amazingly badly put. What the hell is "capacity power"?
And the Monster Digital Charger does not have an output of 600mAh. Presumably, they meant 600mA. They just defined mAh in the last question, but apparently they have a very short memory.
Monster Cable were the first big name in fancy-audio-wire snake oil, and now they've expanded into all sorts of other electrical products, promoted with the same frothy mix of physical fact and fanciful conjecture that they used to sell their first voodoo speaker cables, back in the day. But I expect a certain level of articulateness from a pseudoscientific carpet-bagger; what the heck are Monster thinking, putting up a page like this?
Recalcitrant remote
I recently picked up a Sony Dream System DAV-S300 (surround sound hi-fi/DVD) at the local auctions for a good price, and the user manual states that the Sony remote (model RM-SS300 - they give remotes and systems different model numberss) is capable of controlling a non-Sony television. The manual lists codes which you enter into the remote to select what brand of TV you own.
My problem is that my TV is not listed. It's a 68cm Diamond (aka Mitsubishi?) DFTV-6980. The manual lists codes for other relatively yum cha brands like Magnavox, Daewoo and RCA; it also lists Mitsubishi. But I've tried every code listed for all brands and none work. No, the batteries aren't dead, and I've double checked how to enter codes.
I'm not sure exactly how infrared remotes distinguish between brands, but I assume that it's possible to make a universal remote work with any brand - you just need the correct code.
Andrew
Answer:
It's possible to make a learning remote work with
anything, but pre-programmed allegedly-universal remotes are more limited. If it ain't got a signal-set that matches
your TV (and isn't it fun stepping through them all to see if one does?), you're out of luck.
Remote control codes are basically just simple pulse trains, and there is overlap between them, which is why it's sometimes possible for one device's remote to make another device do something, at least occasionally. But there's enough variation that if the remote can't learn codes it doesn't know, there's nothing you can do to make it work with a gadget that doesn't match one of its existing code sets.
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