Festival of Thrift Repair Café (23-09-2023)

On Saturday 23rd September 2023, I volunteered at a repair café in Billingham Library, which was hosted by Newcastle “Fix it Café” as part of the 2023 “Festival of Thrift“.

I volunteered as support alongside several other members of Climate Action Stokesley & Villages (CASaV), a group who aim to help communities in Stokesley and the surrounding villages to take action on climate change by supporting and developing local initiatives to reduce carbon emissions and/or adapt to the changing climate, primarily through the following major principles:

Energy: reducing energy consumption; increasing renewables usage.
Nature: maintaining the local environment; planting more trees.
Food: promoting sustainable food.
Transport: reducing our reliance on fossil fuel powered vehicles.
Waste: promoting methods of reducing, reusing, and recycling.

Repair cafés focus on waste, specifically by trying to repair items and allow them to be reused instead of being binned or sent for recycling. People are encouraged to bring along items that they need repaired, and to be involved in the repair process themselves – repairs are free, though owners can give a voluntary donation if they’re happy with the service.

Repair cafés usually cater for a large range of items, including:

Electricals (i.e. TVs, vacuum cleaners, kettles, toasters, lawnmowers, etc.).
Electronics (i.e. radios, computers, laptops, phones, tablets, monitors, speakers, etc.).
Furniture (i.e. woodwork, upholstery, etc.).
Textiles (i.e. clothes, bedding, etc.).
Toys (i.e. soft toys, electronics, etc.).
Knives (i.e. sharpening).
Bicycles (i.e. servicing).

CASaV hold regular repair cafés at both Stokelsey (Globe Community Library) and Swainby (Village Hall), so if you’re local, please do consider coming along – either as a guest with something that you’d like to have repaired, or as a volunteer (either for one of the repair teams if you have the appropriate skills and tools, or as support) if you’d like to help.

Stokelsey repair café flyer (image credit: CASaV).

If you’re not local but would still like to get involved, CASaV is only a small part of the International Repair Café movement, so there may already be one closer to you. If not, please consider starting one! The IRC can offer support for this purpose.

So, back to my own experience on the 23rd September 2023. I volunteered as a repairer as part of the electrical/electronics team, alongside several other very helpful, friendly, and committed volunteers – it was a busy session, as it apparently often is (particularly for electricals), and went quickly but was a lot of fun.

I worked on five items, which are detailed below.

Swainby repair café, March 2022 (image credit: CASaV).

Repair #1 – Roland CUBE Street

My first repair attempt was a 1990s Roland CUBE Street audio amplifier, which was brought in by a chap called Alex, who was one of the performers at the Festival of Thrift and was planning on using it later on, but it had started playing up. Apparently, the power switch was only working intermittently, and the amp kept cutting out.

This model uses an external “wall-wart” DC PSU or six AA batteries, which tested OK.

We dismantled the amplifier for further testing, which was easy enough – several screws and hold the amplifier body in place, and the two permanent-magnet speakers are connected using two crimp connectors each.

With it removed, I tested the power switch for continuity with a multimeter, and it was quite intermittent. It also didn’t feel right when switching – it should give a positive “clunk” each way, but it didn’t click on properly. The owner thought it had suffered from water ingress.

The power switch just clips into the chassis. It was connected with two crimp connectors, which were quite loose; I cleaned the switch legs with contact cleaner and a toothbrush as these were quite corroded, then reattached the crimps and tightened them up using a set of needle-nose pliers. The switch itself was a moulded part, so I tried to get some contact cleaner under both ends of the rocker, then worked the switch back and forth a number of times to get the cleaner through the whole switch.

I also took this opportunity to clean and exercise the other controls and switches whilst the unit was apart, and the audio input/output sockets.

We reassembled and tested the unit, and it was now working perfectly. A quick clean up, and it was ready for its show!

Repair #2 – Breville Toaster

My second repair attempt was a 2000s Breville toaster, which was brought in because the second set of toast trays wouldn’t stay locked down.

This is apparently a very common problem with toasters – the trays are held down with electromagnets, but toast and other debris can get in between the magnets and the contacts on the trays, meaning they can’t hold on to one another.

The toaster was easy enough to dismantle – eight triangle-headed screws hold the upper casing on, including one hidden beneath the crumb trays.

With the upper casing pulled up, you can clean out all of the crumbs and other mess with a toothbrush, concentrating on the contacts on the electromagnet transformers and the contacts on the toast trays – this one had a lot of debris inside, so it’s no surprise it wasn’t working properly. The contacts should also be cleaned with a cloth and some IPA.

We reassembled the toaster to test it out, and it now worked perfectly.

Repair #3 – Realistic DX-343 Radio

My third repair attempt was a 1990s Realistic DX-343 clock radio, which was brought in because the batteries were rattling around and it wouldn’t power on.

I took a quick look inside, and the battery contact on one end of the battery compartment which connects two of the four AA batteries together was actually missing. It was probably lost some time when the batteries removed, and it fell out.

The contact didn’t have any wiring to it as it just joined two batteries, and it was held in place with a set of clips. I made a temporary replacement out of some aluminium foil, and the radio powered up OK; one of the other repairers then manufactured a more permanent replacement part using some aluminium sheet and copper tape.

Repair #4 – Black & Decker Drill

My fourth repair attempt was a 1990s Black & Decker power drill, which was brought in because the mains cable had some damage to it which had been temporarily covered using electrical tape, and the switch was quite sticky.

The drill was easy enough to dismantle – two cross-head screws hold the cover in place – and it was very simple inside.

The mains input, the switched live/neutral output to the motor, and a 100nF mains filter capacitor were all held into the switch block with push-fit contacts, which were very fiddley and fell apart as the switch block was unclipped open.

The inside of the switch block was filthy, so I gave it a good clean out with some contact cleaner and a toothbrush. The mains cable was easy enough to repair by cutting it down by a few inches. The mains inputs and the switch outputs were barely held in place by the push-fit contacts, so we decided to solder them all in for a more reliable connection.

The drill was reassembled and had a quick Class II (non-earthed) PAT test before we could power it up. The drill then worked fine with the fixed mains cable and cleaned switch.

Repair #5 – Pioneer CLD-D515 Laserdisc Player

My fifth repair attempt was a 1990s Pioneer CLD-D515 laserdisc player (very cool, right up my street!), which was brought in because it wouldn’t power up properly – the standby LED would light up dimly, but the unit wouldn’t respond to the power switches on either the front panel or the IR remote.

This machine is a very complicated piece of kit, with several complex mechanical assemblies, laser assemblies, and several digital circuit boards – debugging these would take a significant amount of time.

The symptoms seemed to point to a power issue, though – the unit has a self-contained switch-mode power supply (SMPS), which is apparently a common failure point. You can just about see the PSU in the pictures below.

Pioneer CLD-D515 laserdisc player interior.

A SMPS typically takes an AC mains input and converts it to various DC voltages for powering different parts of a system (i.e. motors, digital electronics, etc). These usually all operate in a similar manner, no matter what the SMPS is for.

Thankfully, the CLD-D515 still has service documentation available online, which includes a power supply schematic and parts list.

NOTE: mains-powered equipment contain potentially lethal high voltages that can remain long after the equipment has been powered off and/or unplugged. Experience and the proper safely precautions are required to work inside such equipment safely. This is not a how-to guide; work on mains-powered equipment at your own risk.

We managed to get the PSU out through the side of the unit without removing the tray mechanism, as the tray can be manually opened by turning a grey wheel behind the power button. The PSU connects to the mains with a two-pin clip plug, and to the unit with a two-pin pull plug and a 20-way ribbon connector – be very careful when removing these, as they are delicate. The PSU is held in place with two screws, a plastic standoff (unclipped from the bottom of the case), and two plastic stands (that it slips into).

After a quick visual inspection, nothing seemed obviously wrong – you can see from the scorching on the underside of the board that the big power resistors have been running hot, which is to be expected, but this causes stress on their solder joints and the components around them.

A common problem with these specific PSUs is apparently failed electrolytic capacitors – aluminium electrolytics usually use a liquid electrolyte which dries out and/or leaks over time, lowering their capacitance and increasing their series resistance, and potentially causing corrosion to the rest of the board. This process is accelerated by heat.

One problem part is C12 (1uF 400V radial), which is a startup capacitor that powers up the rest of the SMPS – if this fails, the PSU won’t start properly. It is surrounded by hot parts (a bridge rectifier, a power transistor and heatsink, and some big power resistors) and has very little airflow, so they get baked out and commonly fail.

Being a high-voltage electrolytic, this is quite a specialist part, and we didn’t have any in stock at the repair café. I knew that I had one in my personal stash, so I offered to take the player back to my shed workshop and attempt the repair for the owner at home.

My shed workshop, with various projects.

In the shed, it was a quick process to remove C12 using my desoldering station. I tested it using my Atlas ESR meter, and it had indeed failed.

Because the PSU runs hot, because the output capacitors are run hard in SMPS units (high-frequency smoothing), and because I’ve had problems with ELNA-brand capacitors in the past, I decided to just replace all of the electrolytic capacitors on this power supply with high-quality modern equivalents – in total, this was:

I also checked all of the primary and secondary fuses (there are six total, including two thermal fuses sandwiched between the output transistors), reflowed the solder joints on components with mechanical or thermal stress (i.e. transformers, connectors, transistors, power resistors, the bridge rectifier, etc), and cleaned all of the connector sockets with contact cleaner.

I refitted the PSU into the machine, taking care not to damage the delicate ribbon connector. I also gave the machine and remote a good clean.

Pioneer CLD-D515 laserdisc player reassembly.

With the power supply reinstalled and the unit reassembled, the laserdisc player now seemed to start up correctly – very exciting! The owner lent me a Species laserdisc to test the player out with, and it now seemed to work perfectly, even with the IR remote.