Zachary Madin

Zachary Madin

Robotics PhD Student focusing on collective dynamics

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Posts

Future Blog Post

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portfolio

publications

Collective Anomaly Perception During Multi-Robot Patrol: Constrained Interactions Can Promote Accurate Consensus

Published in ACM/SIGAPP - Avila, Spain, 2024

We find that generally, MRP algorithms that promote physical mixing of robots, as measured by a higher connectivity of their emergent communication network, reach consensus more quickly.

Recommended citation: Madin, Zachary R and Lawry, Jonathan and Hunt, Edmund R, . (2024). "Collective Anomaly Perception During Multi-Robot Patrol." SAC 2024 1. 1(1). Paper link here.

repair

Audio Amplifier

Repair No. , 1900

Problem:    USB connector not connecting 
Solution:   Re-solder connector 
Brand:  Generic 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Bluetooth amplifier wouldn’t accept a charge from the USB cable, when looking closer the micro-usb connector had been bent off, and pulled a bunch of the traces with it off the PCB! Managed to re-heat the connector and push it down to make a connection again, and then plopped some epoxy over the back of the connector to take some of the strain out.

MacBook water ingress

Repair No. , 1900

Problem:    Water damage 
Solution:   Replace FPC connector 
Brand:  Apple 
Cost new:   £800 
Cost of fix:    £4 
Age:    TODO 
Success?:   Yes

Water got spilled on a friend’s laptop, and would turn on but the screen didn’t show anything. Taking it apart showed the connection from the mobo to the screen had a short and melted and damaged the screen connector. The whole connector would have to be replaced, which I’m going to do once I source the right component and reset the laptop.

Marshall Bluetooth Headphones

Repair No. , 1900

Problem:    No Bluetooth 
Solution:   Replace battery and NTC 
Brand:  Marshall 
Cost new:   ??? 
Cost of fix:    £12.00 
Age:    TODO 
Success?:   Yes

Pair of Marshall wireless headphones that would work if you plugged an audio source into the 3.5mm audio jack, but wouldn’t boot and accept a bluetooth connection. Opened them up, and the battery was entirely dead! Sourced a replacement that would fit inside the headphones, but they didn’t come with an NTC resistor like the original battery. Bought a replacement NTC and put that in a suitable position and it all works fine! The standard NTC for this battery was a 10kR, but it’s worth checking with the original as if you choose the wrong ranged resistor, the onboard micro might consider it as a fault!

PA Kit

Repair No. , 1900

Problem:    Went bang! 
Solution:   Replace drivers and board components 
Brand:  QTX Sound 
Cost new:   £600.00 
Cost of fix:    £118.28 
Age:    TODO 
Success?:   Yes

Guys came in with a PA set that had been plugged in when the bassist incorrectly wired up one of their pedals/amplifiers, then there was an awful sound and a disgusting smell, according to them. Had a cursory look at the PA deck, to make sure nothing was wrong there and didn’t see anything immediately broken. Open the speaker cabs and look at the pre-filters and the 20W resistor as part of the RLC filter had gotten so hot the legs had exploded out of both speakers! The thermal fuse on both boards inside the speakers had exploded and released their magic smoke. One of the cones sounded pretty damaged, my rubric for that being if you push in on one of the cones and hear a ‘crinkly’ sound, like a crisp packet being rustled, the driver is damaged. One speaker cone sounded exactly like that, and the other one sounded similar bit not as bad. I asked the people who brought them in, and they were happy to replace both of them at the same time so they’d sound close to similar. A colleague contacted the speaker manufacturer and suggested a replacement driver, so sourced that. Then purchased replacement components for the board and re-soldered the new ones on – sourced from https://willys-hifi.com which was a great site for this. Nice and easy fix, if a little expensive for the customers.

Portable Projector – Dead Battery

Repair No. , 1900

Problem:    Dead battery 
Solution:   No Fix 
Brand:  Harmon Kardon 
Cost new:   £300 
Cost of fix:    0p 
Age:    TODO 
Success?:   No

This projector came in that wouldn’t boot at all. It’s a portable mini projector, but no buttons would do anything and wouldn’t work. Started to disassemble, and checked the battery which was totally dead! You can’t get replacements for this battery because it’s got to be a specific size in order to fit inside the container. Unfortunate very expensive and sophisticated bit of kit all to end up as junk because you can’t get a replacement battery, and you can’t run it by having it plugged in!

Bang-polar Junction Transistor

Repair No. , 1900

Problem:    Exploded BJT converted to dust 
Solution:   Replace BJT and board 
Brand:  Unknown 
Cost new:   £20.00 
Cost of fix:    10p 
Age:    TODO 
Success?:   Yes

A magnification and combined lamp wouldn’t turn on the lights found in the recycling bin. Taking it apart there’s a simple potentiometer that controls the current to the LEDs via a BJT that had exploded and taken the PCB with it. Jury-rigged a simple circuit on perfboard that connects to the potentiometer that achieves the same thing. It is now my desk magnification for when I need something extra!

Microwave

Repair No. , 1900

Problem:    Won’t produce heat 
Solution:   Scrap 
Brand:  Generic 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   No

Don’t usually look at microwaves, but thought it might be an easy fix of a dodgy connector, as the screen would turn on and you could change dials and settings, but didn’t actually ‘go’ and start powering the microwave. I thought it would be an issue from the push buttons not making a good connection, but they all worked properly. Unfortuantely probably something with the electronic portal to hell that heats the food. Into the scrap it went, but we kept the control board to salvage components as and when we need them.

Ultra 1968 Vinyl Player

Repair No. , 1900

Problem:    Terrible sound quality 
Solution:   New pre-amplifier transistor 
Brand:  Ultra 
Cost new:   ??? 
Cost of fix:    10p 
Age:    TODO 
Success?:   Yes

TODO

Magnifier Light

Repair No. , 1900

Problem:    Would not turn on (dead transistor) 
Solution:   Replace transistor and board 
Brand:  Unknown 
Cost new:   ??? 
Cost of fix:    80p 
Age:    20yrs+ 
Success?:   Yes

This was something found in the recycling bin that I thought we could use. A DC powered magnifier and light. Opening it up revealed an absolutely catastrophic death of some poor transistor that had turned to DUST!. I removed the board as it had cracked in half as well. Replaced the circuit with something on stripboard to have an adjustable current source to drive the LEDs. It is now used in our cafe to repair other things!

Microphone Screen dodgy

Repair No. , 1900

Problem:    Lines on screen 
Solution:   Clean connector 
Brand:  TODO 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Device works fine in terms of recording audio and turning on, but there are a series of lines on the screen that don’t disappear and never turn on. Open it up, and the ribbon cable connection from the screen to the mainboard was old and slightly corroded and making a bad connection. Used a bit of switch cleaner and a Q-Tip to clean up the connector and the issue disappeared!

Slow cooker

Repair No. , 1900

Problem:    Wouldn't turn on or heat up 
Solution:   Reset thermal fuse 
Brand:  Unknown 
Cost new:   £250 
Cost of fix:    0p 
Age:    2yrs 
Success?:   Yes

This was quite a fun one that I did, as it wasn't working and all and wouldn't turn on. Usually with these things it's a thermal fuse that dies, so checked those, and no issue there. After pondering, and other volunteers pondering I left it for a while. Then another volunteer who took over found that there's a dedicated resettable thermal fuse that you have to press down to reset! This was written nowhere in the manual though!!!!

Lamp

Repair No. , 1900

Problem:    Not turning on 
Solution:   Re-solder connections 
Brand:  Generic 
Cost new:   £20 
Cost of fix:    0p 
Age:    1yr 
Success?:   Yes

Nice and easy fix, disassemble and re-solder wire that had snapped!

Repair No. , 1900

Gunky bearing

Repair No. , 1900

Problem:    Wouldn't spin 
Solution:   Clean main bearing 
Brand:  Bosch 
Cost new:   £75 
Cost of fix:    0p 
Age:    3yrs 
Success?:   Yes

The main bearing for the rotor had siezed up from too much dust entering it! Tried to press off the bearing to see if we could replace it, but was not budging. Method instead was to flood the bearing and twist it by hand to crush the dust and muck inside the bearing, and keep flooding it with oil so that the detritus leaked out of the bearing. With enough spinning and oil it ended up clean enough and worked happily. Extended the life a bit more of this sander!

Infernal Coffee machine

Repair No. , 1900

Problem:    MYSTERY 
Solution:   ALSO MYSTERY 
Brand:  Jura 
Cost new:   £1250 
Cost of fix:    0p 
Age:    0p 
Success?:   Yes

Coffee machine that came in from one of the stalls in sparks that would have an error during the boot up sequence. It would give some error code on the screen that didn’t describe much and Google searching came up with no information! I could hear a relay engaging before it switched off, so there must be some software deciding to turn itself off, so I figured that the code was successfully executing but some status during the bootup sequence was bad and engaged some safety process. I spent the end of many sessions trying to get into this thing, and then diagnosing it. Both of the control boards were fine, no visible issues that screamed error. Started unplugging cables that went to the control board to see which one triggered the fail state, and eventually found a 2-cable connector that would cause it to fail the boot process. When I unplugged it, it was able to get past that auto shut off, but then returned an error later in the boot process saying that something was disconnected. Followed that cable and it lead to a pressure sensor of sorts that wasn’t well connected, so I think it just wasn’t making electrical contact! Re-connected it and reassembled the machine, and then got to enjoy a cup of coffee from the machine. Very satisfying cup of coffee!

Mangled Cable – Scooter

Repair No. , 1900

Problem:    Exploded PCB from cable being crushed 
Solution:   No Fix 
Brand:  Halfords 
Cost new:   £90 
Cost of fix:    0p 
Age:    TODO 
Success?:   No

Scooter came in, it wouldn’t turn on at all and the electric motor wouldn’t spin. Taking it apart, when looking at the PCB there was a very obvious track that had gotten so hot it de-laminated itself and burnt the copper track such that it was an open circuit! When taking it further apart, what had happened was the control and power cables that go up to the control module, had been crushed in a pinch point in the scooter stem, causing a GPIO line to the microcontroller to get a whopping 24V! This was the GPIO line that measures the throttle, so once I’d sorted and fixed the cable, even though it would turn on, and the micro would do something (send signals to the gate drivers), the GPIO pin on the micro was toast, and the entire thing would have to be replaced. As the code to flash the micro is unavailable, it is essentially un-fixable. I looked online for suitable brushless motor controllers at 24V, but couldn’t find one that would fit the requirements for the scooter. Unfortunately, the whole electric portion of this scooter is now broken. It still functions as a scooter though!

Kobo Reader Leak

Repair No. , 1900

Problem:    Water damage 
Solution:   Scrap 
Brand:  Kobo 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   No

E-reader had a bit of moisture ingress from something being spilled on it. Opened it up and there was a bunch of backlight LEDs that had shorted and exploded, which meant that the LED power rail had been ruined. Removed the offending LEDs and followed the rail back to the source, but still wouldn’t generate the voltage required. Followed the connection from the LED to a chip that controls the screen matrix, and there’s some issue there, but there is no documentation available for that chip, so it’s basically a dead end at that point. The parts did not go to waste however! The battery has gone towards a project I’m working on that needed a nice flat battery!

Dodgy Strimmer Connection

Repair No. , 1900

Problem:    Snapped connection on motor 
Solution:   Re-solder power cable 
Brand:  Generic 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Electric strimmer wouldn’t turn on and move, but all the connections from the plug to the cables seemed fine. Turns out inside the little choke before the motor connection, under the heatshrink, the spool of wire had been twisted too much and needed re-soldering. Nice and simple fix once the issue had been found!

Blinds Mechanism

Repair No. , 1900

Problem:    Jammed mechanism 
Solution:   Disassembly and removal 
Brand:  Unknown 
Cost new:   £20 
Cost of fix:    5p 
Age:    Unknown 
Success?:   Yes

Somebody brought in a set of blinds that weren't tilting at the angle anymore. Turns out part of the worm gear that turns it had snapped off and gotten stuck in the screw! Ended up disassembling them in order to remove and re-riveting the mechanism back together

CD Player Tray

Repair No. , 1900

Problem:    CD player would not play 
Solution:   Replace belt and lubricate mechanism 
Brand:  Denon 
Cost new:   £150 
Cost of fix:    0p 
Age:    5yrs 
Success?:   Yes

"Customer brought in a CD player that wouldn't play a CD and would just keep sticking. It would open and receive a CD, but then would get stuck on track 1 and never play. Turns out running the mechanism with the shell off revealed that the tilt mechanism to engage the motor wasn't being activated properly. The belt that had the job to activate the mechanism to tilt was just spinning in place and never being activated. Replaced the belt with a suitable one and added some drops of oil on the plastic parts that wipe together and it loads and plays CDs correctly!"

Coffee Grinder Not Grinding

Repair No. , 1900

Problem:    Grinder would not turn on 
Solution:   Re-solder connection 
Brand:  Generic 
Cost new:   £60 
Cost of fix:    0p 
Age:    2yrs 
Success?:   Yes

"Coffee grinder came in that just suddenly stopped working one day. Opening it up didn't make much sense as all the components looked fine. Trying to follow the connections to the motor revealed that one of the terminals of the motor wasn't connected. Upon closer inspection the wire connection had somehow snapped!"

Dodgy Charger Port

Repair No. , 1900

Problem:    Won't charge unless held in position 
Solution:   Replace charging port 
Brand:  Lenovo 
Cost new:   £450 
Cost of fix:    £12 
Age:    4yrs 
Success?:   Yes

Customer brought this in who didn't have the funds to take it to a repair shop so we replaced the charging port for them if they paid for the parts. The issue was the connector in there relies on a piece of sprung metal to make a connection with the terminals. This over time had snapped and now only made a contact if you forced the charger into the socket, so less than ideal. Purchased a port component and soldered it at home where I had my high powered soldering iron as it required quite a bit of heat to flood the many layers in the motherboard! Often for a job like this if I don't care about the component I'm removing, I'll destroy/disassemble it in place so that less heat is being removed from my iron, so the remaining parts are smaller and require less heat to remove and I'm thus less likely to damage the board from heat. Soldered the new one in place and happily charges now.

Torpedo timer (Yes that cool)

Repair No. , 1900

Problem:    Wouldn't wind up 
Solution:   Forward to watch maker contact 
Brand:  Robert North and Sons 
Cost new:   £2450 
Cost of fix:    0p 
Age:    ~75 years 
Success?:   No

Well this was an incredible first. A torpedo clock timer from the second world war!! Somebody brought this is because they wanted help figuring out why it didn't work, and how to fix it. This was by far the coolest thing to come into the cafe! The issue in the end is that one of the gears for winding up the coil had been damaged and the teeth were stripped off the gearface. We have a volunteer that knows somebody who manufactures custom gears for precisely this kind of application so we passed on their number and wished them the best.

Portable Coffee Grinder

Repair No. , 1900

Problem:    Motor wouldn’t move grinder 
Solution:   Insert missing circlip 
Brand:  UFIT 
Cost new:   £25.00 
Cost of fix:    1p 
Age:    TODO 
Success?:   Yes

Grinder was donated in the junk box, that would hold a charge and you could hear the motor spin, but the actual grinder mechanism wouldn’t engage. Open the device up and one of the circlips that holds the attachment in place had snapped or come loose, and now the thing was fixed for the cost of a 1p circlip! One of our volunteers is using it to grind up egg shells to make egg shell porcelain with!

Coffee Switch

Repair No. , 1900

Problem:    Button won't work 
Solution:   Glue flexible plastic 
Brand:  Generic 
Cost new:   £45 
Cost of fix:    0p 
Age:    3ys 
Success?:   Yes

We have had three of these into the cafe, all with the exact same problem. They use a piece of plastic to act as the spring for the on button, which over the liftime snaps and breaks. Thus the button becomes stuck and does not activate. The solution we have found works well is to use some hard plastic that flexes a bit and glue or drill it into a support structure.

Hand(le) off my guitar!

Repair No. , 1900

Problem:    Handle came off 
Solution:   Braided steel wire with rivets 
Brand:  Generic 
Cost new:   £60 
Cost of fix:    20p 
Age:    15 yrs 
Success?:   Yes

Somebody brought in a guitar case that the handle came off, that they were having issues trying to reattach. We agreed that a good solution that would still allow the handle to 'swing' would be to thread braided steel wire and rivet the wire in place through the body. This involved peeling back the fabric lining to expose the mounting holes, then feeding the wire through and then riveting the pieces in place in the hole. Definitely not going anywhere, so a safe guitar!"

Repair No. , 1900

PARTY

Repair No. , 1900

Problem:    Won't turn on 
Solution:   Replace transistor 
Brand:  Generic 
Cost new:   £40 
Cost of fix:    60p 
Age:    3yrs 
Success?:   Yes

Annoyingly I don't have a photo of the original transistor that met a grisly end. Neon party light that had the transistor that exploded dramatically. Was a nice and easy fix to get one from our generic parts drawer, and solder it in and works like new!

Repair No. , 1900

Shredded gears with your e-bike sir?

Repair No. , 1900

Problem:    Shredded planetary gears 
Solution:   Replace gearbox and bearings  
Brand:  Unbranded 
Cost new:   £800 
Cost of fix:    £25.00 
Age:    TODO 
Success?:   Yes

We had this e-bike that was donated to the repair cafe, that no longer worked and the person involved didn’t want it back as they had an upgrade and had been told it was unfixable. Bit of diagnosing later, as I could get the motor to spin with the throttle, but the wheel itself would stop and start and stutter, which didn’t make much sense. I knew that the battery was fine as I could test the voltage on that, and as it’s a brushless motor and controller, it didn’t make much sense why the wheel would stop/start/stop, so seemed more of a mechanical issue. So I removed the whole motor connectors and opened the housing for the in-wheel motor. Inside the housing was a disgusting mix of black grease, along with the remains of the nylon planetary gears that had been absolutely shredded to the extent that they were basically smooth around 2/3 of the gear face! This made sense why the wheel would spin for a little bit and then stop! When I was re-assembling the motor housing I found out why the gears had shredded themselves to bits however! The bearings for the motor were totally seized and would not budge in the slightest!! So the motor and gearbox would have been straining against seized bearings which would allow a bit of movement and then stop, which is most likely why the gears got shredded. Bought a bunch of new bearings and pressed those in happily. Then I had to source a replacement planetary gear set and re-grease it and assemble which all was possible and found the exact match of nylon pair and flooded the gearbox with a bunch of high temp grease and it works like a dream. I still get messages from the person who eventually got it who is very happy with it and has no issues

Black Magic Smoke Machine

Repair No. , 1900

Problem:    Bang 
Solution:   Scrap 
Brand:  Generic 
Cost new:   £15.00 
Cost of fix:    0p 
Age:    TODO 
Success?:   No

Only including this because it was kind of funny. Somebody brought in this power adapter as it no longer worked, and when I handled it I could hear something rattling. Opened up the case and immediately saw the issue! Multiple components had exploded and were specks of dust in the case. Not worth repairing something this cheap and this destroyed, but fun to see what happens when the magic pixies don’t cooperate.

Roberts Radio Switch

Repair No. , 1900

Problem:    Won’t switch FM/DAB Mode 
Solution:   Replace tactile switch 
Brand:  Roberts 
Cost new:   £110.00 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Somebody brought this radio in that would turn on, but the ability to switch between FM and DAB mode wouldn’t work. Taking it apart, it was just a small tactile switch that had maxed out the lifecycle. We had another sacrificial Roberts Radio that I could salvage the switch from, and worked very happily after that. Was a bit of a pain to get at the thing however!

Akai Turntable

Repair No. , 1900

Problem:    Can't sync direct drive  
Solution:   Switch cleaner on potentiometers 
Brand:  Akai 
Cost new:   £300+ 
Cost of fix:    0p + £20 
Age:    Unknown 
Success?:   Yes

This was a turntable that was found in the recycling bin, which we thought must be able to be fixed. Powers on, but as it's a direct drive turntable, you need to ensure the marks on the disc are synchronised with the pulsed light. These are controlled by the trimming potentiometers, which no matter how much you spinned them they didn't seem to synchronise. Opened the unit and squirted a bunch of switch cleaner into the potentiometers and there we go! When we put a record on however, we realised the stylus had been terribly abused and is missing the sharp diamond point. A new stylus is on order for £20 and we are seeing what we can do about the counterweight. This will go on to be sold at the cafe to keep our funds going.

Hair Straighteners

Repair No. , 1900

Problem:    Intermittently turning off 
Solution:   Re-solder wire connection 
Brand:  Unknown 
Cost new:   £160 
Cost of fix:    0p 
Age:    8 yrs 
Success?:   Yes

Customer brought this in, and she had the issue that when you would turn it on and use it, they would suddenly turn off! Opened them up and found that one of the main power connections to the heating element had snapped due to movement. Re-solder it and crimp it down and it works happily. One interesting note about these straighteners is that they do not have a sensor feedback to detect temperature that I could spot, so they must work on calibrated heat elements and some form of current control with a known power loss. Quite clever design inside too.

Kindle

Repair No. , 1900

Problem:    Stuck on screen 
Solution:   Send to Amazon for voucher off new kindle. Dead battery 
Brand:  Amazon Kindle 
Cost new:   £80 
Cost of fix:    0p 
Age:    5 yrs 
Success?:   No

Customer brought in this Kindle that was stuck on the last page she read, and wouldn't charge at all. Opened it and measured the battery voltage which should have been 4.2V, when charging it would tick up but the second you removed the charging port the voltage would instantly drop back down. It is possible to buy replacement batteries for Kindles, but Amazon also runs a scheme where you can trade in kindles for vouchers and money off a new kindle so that's what the customer did, as it was an old model anyway.

Repair No. , 1900

Air Fryer

Repair No. , 1900

Problem:    Dead thermal fuse 
Solution:   Replace thermal fuse 
Brand:  Generic 
Cost new:   £60.00 
Cost of fix:    20p 
Age:    TODO 
Success?:   Yes

Air fryer came in not working at all, 99 times out of 100 with things like this it’s going to be the thermal fuse. The issue is taking the sodding thing apart! Very much not designed to be serviced / fixed considering the fix is a 20p thermal fuse that needs to be replaced…

Repair No. , 1900

Marantz Amplifier

Repair No. , 1900

Problem:    TODO 
Solution:   TODO 
Brand:  Marantz 
Cost new:   TODO 
Cost of fix:    TODO 
Age:    TODO 
Success?:   TODO

TODO

Dead Charger Shaver

Repair No. , 1900

Problem:    Dead charging circuit 
Solution:   Scrapped for parts 
Brand:  Phillips 
Cost new:   £60 
Cost of fix:    0p 
Age:    1yr 
Success?:   No

Somebody brought this shaver in as it wasn't charging or working at all. Taking it apart reveals a battery that is dead, but the charging circuit was also dead! No volts provided to the battery by the charging cirucit when plugged in. No schematics available so impossible to fix.

Xbox One HDMI

Repair No. , 1900

Problem:    No HDMI signal received 
Solution:   Replace HDMI chip on motherboard 
Brand:  XBOX 
Cost new:   £100 
Cost of fix:    £5.15 
Age:    UnknPAown 
Success?:   Yes

Another volunteer said that they had come across a similar issue with xbox ones at another repair cafe, so this was nice and easy to diagnose! No HDMI signal on the output, but it boots up and displays the necessary lights. Identified the required HDMI timing IC and bought one (SN75DP159RSBR). Removed the old chip with my rework station and soldered the new chip on. Jobs a goodun!

Bad IMU Production

Repair No. , 1900

Problem:    Shorted connection on IMU 
Solution:   Remove excess solder 
Brand:  DFRobot 
Cost new:   £75 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

This is an issue I had during PhD, where we’d purchased a few IMUs at once and one of them just wouldn’t boot and wouldn’t turn on. I couldn’t resist opening it up and having a look at what the issue was. Turns out the IMU chip itself had an issue during soldering, causing 3.3V to be shorted to ground, as you can see in the photos. This was quite surprising, as if 3.3V was shorted, it wouldn’t have been possible to flash the devices in the factory with the microcontroller code? The corresponding microcontroller is powered by 3.3V, so it needed that rail to be correct. The manufacturers obviously didn’t have a check to see if the micros were successfully flashed! We got a full refund once we showed these images

Camera Lens Stuck

Repair No. , 1900

Problem:    Lens stuck opening 
Solution:   Bit of oil on mechanism 
Brand:  Canon 
Cost new:   ~£50 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Camera came in that had issue automatically opening the lens covers when booting. Disassemble and very precisely add a tiny dab of oil on the mechanism that releases/retracts the covers. Cycle the camera a few times and now the mechanism opens happily. Pretty sure a collection of dust and nasty stuff gunked up the mechanism

Til’ the wheels come off

Repair No. , 1900

Problem:    Wheel kept slipping off a trolley 
Solution:   Widen diameter of axle 
Brand:  Generic 
Cost new:   ??? 
Cost of fix:    2p 
Age:    TODO 
Success?:   Yes

The wheel of a pull trolley kept falling off. Disassembling the mount, the plastic that holds the wheel on had lost the bend that it needs to hold the wheel on. I wrapped a load of teflon plumber’s tape around the axle to thicken it, and then forced the wheel over the bump so that it won’t come off again. Happy quick fix

Sony Walkman

Repair No. , 1900

Problem:    Intermittent audio connection 
Solution:   Get a replacement 3.5mm  
Brand:  Sony 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

The audio jack would only work if you pressed the audio jack in at a certain angle, so this was an obvious fix. Re-solder the connector and make sure it is making a good connection and not likely to pry off again.

(Leaky) Water Feature

Repair No. , 1900

Problem:    Won't turn on 
Solution:   Clean up solder connections 
Brand:  Generic 
Cost new:   £30 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

TODO

Broken Blinds

Repair No. , 1900

Problem:    Trapped mechanism 
Solution:   Re-attach string and fasten 
Brand:  Ikea 
Cost new:   £80.00 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Blinds came in that weren’t able to retract properly, the issue was that the string had come loose in the mechanism,and needed to be re-fed through the spindle and fixed in place.

Vacuum

Repair No. , 1900

Problem:    Belt had burnt through 
Solution:   Replace belt and clean head 
Brand:  Unkown 
Cost new:   ??? 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

The vacuum would create suction, but the head of the vacuum wouldn’t spin to pull up hair and dust. Having a look inside, the mechanism had gotten gunged up and was impossible to spin, and the belt to attach from the motor to the head had melted through. Thankfully the customers brought in a spare belt that came with the vacuum cleaner! Nice and easy fix to clean out the mechanism so that it could spin freely, and attach the new belt.

Headphones cable issue

Repair No. , 1900

Problem:    Intermittent connection 
Solution:   New audio cable 
Brand:  Generic 
Cost new:   £80.00 
Cost of fix:    0p 
Age:    TODO 
Success?:   Yes

Headphones came in that had an intermittent connection and would crackle on one of the speakers. Electrical test between them showed a bad connection in the 3.5mm jack end, and they’d already brought in a 3.5mm jack to replace it with. The quality of the existing cables wasn’t great so I thought it better and easier to swap it out for a moulded 3.5mm jack. Went through the junk collection we have and found a perfectly suitable one to replace it with, that saved the wire getting junked for scrap.

talks

teaching

Teaching experience 1

Undergraduate course, University 1, Department, 2014

This is a description of a teaching experience. You can use markdown like any other post.

Teaching experience 2

Workshop, University 1, Department, 2015

This is a description of a teaching experience. You can use markdown like any other post.