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Showing posts from 2020

Acer Iconia Completed

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Just a quick post showing the repaired Acer Iconia tablet in its snappy red cover. In the foreground is a pair of Bluetooth earphones that were another repair job. I moved a 32Gb SD card from another tablet to this one and added a matte screen protector to make the screen easier to read. All in, a great upcycle which I can use for the next few years.

More Data-logging Experiments

This is just a quick post, really to link to the short video I made below showing my latest data-logging experiment, which takes in a number of technologies. At the core is an Arduino Nano doing the actual logging with code derived from work I did using PIC microcontrollers a few years ago. There are two parts to this - Reading up to 8 10-bit analogue values (range 0-1023); Reading the frequency of a PWM signal. These values are output serially 10 times per second (at 115200 bps) in what I call a data 'frame' which looks like - <AABBCCDDEEFFGGHH> Each frame has 18 bytes terminated by '<' and '>'. The pairs of letters represent a 10-bit value split into 2 5-bit nibbles and these values (0-31) have 64 added to them so that they are displayable ASCII characters to make debugging easier (range is decimal 64-95) Putting these together gives the basis for a data-logging and dashboard display system for my (currently ignored) 1988 Toyota MR2, but it needs a

Quick Repair

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My son's Trust gaming headset developed an intermittent fault with the left earphone. Quick investigation revealed one of the connections had come loose. It didn't appear to have been very well soldered originally. A quick 5-minute repair and they are working good as new.  This type of wire is what my father called Litz wire, but reading up on it that might have been incorrect on his part. My grandfather was a pioneering amateur radio operator and almost certainly used proper Litz wire for radio frequency working on shortwave. Anyway, it is a strong and flexible wire suited to applications such as headphones and microphones, but needs the lacquer removed and to be tinned before soldering otherwise you get a poor joint. 

Acer Iconia One 10 Tablet Repair

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 I received another haul of old electronics from kind Freegle lady Margaret who was having a clear out. There was an old Asus netbook which had died, but it gave up another useful 10.1 inch LCD panel so I have ordered a control board for it on eBay. There were two tablet computers with cracked touch panels, an Asus Nexus 2 and an Acer Iconia. Both tablets booted up and could be reset and used with my Bluetooth combination keyboard and trackpad. A bit of research revealed that the Nexus would be much harder to repair and probably was too low spec to be worth the trouble, whereas the Acer would be an easier repair, was still had a decent spec (Intel CPU and 2Gb or RAM) and had received a final update to Android 7 only 2 years ago. Decision made, I purchased a replacement touch panel for £12 on eBay. Acer Iconia with cracked touch panel (Bluetooth keyboard) While the new touch panel was on its way, I decided to sacrifice the Nexus in the spirit of learning and had a go at removing its bro

Touchpad USB Conversion

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Over 20 years ago, when we were first getting into PCs, my dad got a Chicony KTP-7903 keyboard in a 'goody' box from Bull Electrical. These were large cheap boxes of surplus gear and could be anything, but always had some interesting stuff in them. We even got parts of the duff Rabbit phone system in one. The keyboard was an odd-shaped thing that was supposed to be ergonomic, but it had a touchpad on the removable wrist rest which was pretty unusual. The device had a full-size 5-pin DIN PS/2 connection for the keyboard and a separate serial (RS232) connection for the touchpad. Pretty soon my dad got bored with the weird keyboard but he had the genius idea of carefully cutting the touchpad off the end of the rest and using it separately. It turned out to be really useful anywhere where a mouse was going to be hard to use. The only problem was that it had a serial connection and by about 5 years ago it was obsolete as even the older computers I use no longer had a serial port. I

Minitel Disaster Update

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So I bought this Minitel terminal to play about with for what I thought was a knock-down price, but the seller didn't package it well enough and I ended up with a Minitel that made some nasty noises and didn't work, not even in its native language of French. I got around to taking it all apart and unfortunately discovered that the CRT had suffered terminal damage, which explained the arcing noises. These things operate at a very high voltage so I wasn't about to start mucking around with it, so it went in the bin. I tried connecting the power board back up to the logic board to see if I could get the thing to at least switch on, but that didn't work either so I have to assume that the damage is more extensive. When I get time I will try and decode the signals on the 8-pin connector between the power and logic boards and see if I can power the board directly. Apparently one of the lines is a video feed, but it is in a non-standard format. I should be able to get somethi

All Upgraded or Repaired

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Putting all of it together, here is my recently upgraded HP Pavilion G6 laptop connected to the 39-inch ISIS television ( see post here ), both of which were given to me as broken items by kind people of Freegle. I bodged a backlight repair for the TV for nothing using scrap LEDs, which lasted over a year and when that failed I took a punt and bought a new set of backlight LED strips on eBay for about £15 rather than dump a good large-screen television. It is now working so well, I spent £4 on eBay and bought a remote for it as the original one was missing. Fortnightly 'Virtual Pub' in lock-down with my friends from all over the world, we even had an old mate join us from Singapore even though it was 3 am there! The camera is my dashcam in USB camera mode (I haven't been driving much as I'm working 12-hour days from home instead). The laptop can cope with the big screen only in this set-up otherwise the GPU tends to overheat. Oh, I n

Laptop CPU Upgrade

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So I decided to go for the ultimate upgrade on my trusty HP Pavilion G6 laptop which was given to me 3 years ago by a kind guy on Freegle. At the time I had to replace the fan and keyboard to get it going ( see post here ), but this upgrade was at another level entirely as I've never swapped out a laptop CPU before.  A lot of research went into this to make sure I was getting the right APU (combined CPU and graphics processor or GPU), because the same motherboard can work with a wide range of Intel and AMD processors. I went for broke and got the most powerful one the motherboard could handle for £20 on eBay along with an additional 4Gb RAM to bring it up to 8Gb. Here is the old 2-core APU (E2-3000M) ready to be removed. And the replacement 4-core APU (A8-3520M) installed with a smearing of heatsink paste ready for reassembly. So did it work? Thankfully yes and I am editing this post using the computer. The GPU runs a little hot which I am keeping an eye on,

Case in Point

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So a few years ago I got a broken one of these. I stripped it out for parts and the other day finally got round to cutting a new front and back for it. Now I just need a retro project to put in it, but the internet clock is the top contender.

Bosch 24-volt Cordless Drill Motor

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My brother-in-law dropped this broken Bosch cordless drill round a few weeks ago. After leaving it in quarantine for 72 hours I stripped it out for a look. After getting the 24-volt motor separated from the chuck it became obvious something was wrong because the motor wouldn't turn smoothly and was jamming. My first thought was that some debris had got inside the motor, but after prizing off the end the problem became clear, the two permanent magnets had come loose. I thought this was odd for an expensive drill with one of these legendary Bosch motors, but maybe it was a Friday afternoon one. A look online and on eBay wasn't promising, I could only find one possible replacement and it would cost €60 + shipping. The first attempt at glueing the magnets back in failed, but I hadn't mixed the epoxy properly so I'm giving it another go and this time I'll leave the thing for 72 hours as recommended to let the epoxy cure completely. I h

School At Home IT Solutions

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I work in education and recently have been in contact with a number of schools in Northern Ireland, Scotland and a couple in England to find out what barriers students are encountering in continuing their learning from home. While a small number of families are reporting problems with their broadband connections, by far the biggest barrier is actual IT hardware. Often this is in families with three or more children where there are not enough computers to go around, especially if mum, dad or both are also working from home. An announcement was made by the Department of Education in England last week that IT hardware would be available for loan to students and some schools in NI have already lent laptops to students, but there are nowhere near enough to go around. Now obviously in our house we are spoilt, but only because we up-cycle 'obsolete' IT equipment and run everything on Linux, but that hasn't stopped me looking at possible solutions for others. It occurred to m

Earpiece upgrade

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I bought this little earpiece a few months ago to listen to audio books on my mobile 'phone when I'm out walking. I don't like wearing a pair of earphones when I'm out at night, situational awareness is important to me! The sounder is in the bulge and there is a rubber air tube up to the Secret Service style earpiece. The earpiece wasn't very successful. The tube was too short and there wasn't much sound. A quick test showed the single sounder was only wired to one side of the stereo output. I took a salvaged 3.5mm stereo cable and soldered it directly to the plug on my earpiece, but with both left and right signals combined. A bit of heatshrink sleeving (greatest invention ever) and all sorted. Now double the sound and a longer run to my 'phone. Listening to 'Zen and the Art of Motorcycle Maintenance' at the minute.

Minitel Disaster

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About 25 years ago my late father got hold of a French Minitel terminal unit that was being dumped. He was the stores clerk for the local council and the lads that managed the dump put old computers to one side for him. It was one of the things that I lost when my first marriage broke up and I have always wanted to get another one to mess about with. The Minitel terminals were for a telephone based information system, but also had an RS232 serial port so can be hooked up to an Arduino or Raspberry Pi. A Philips Minitel 2 appeared on eBay and since nobody else was bidding I got it for £15 including postage which seemed too good to be true. Which it was. The seller didn't pack it with any bubble wrap, just an old cardboard box, and it arrived broken. Specifically, the CRT tube had come loose inside the case. After a bit of fuss I was only able to get a refund of £5 so I have a broken Minitel terminal worth a tenner. So is it repairable? Only time and effort wi