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>> No. 2479 Anonymous
8th January 2019
Tuesday 8:18 pm
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Has anyone built a homemade class A amp? I'm looking for schematics but it seems like there's no real consensus on the pros and cons of the designs. I do want to use transistors instead of tubes simply because they're easier to find.
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>> No. 2482 Anonymous
9th January 2019
Wednesday 10:38 am
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30W/channel of class A is going to be quite hot, regardless of whether it's idling or running flat out. Any particular reason why you think Class A is what you want?
It really is the wrong way to build audio amps, unless you're working under some quite peculiar constraints.
If you're doing it for fun, then knock yourself out, there's no great difficulty to it - they're simple enough, especially as I imagine you'll also be eschewing feedback.
Note that most modern MOSFETs are crap at being analogue transistors, they're designed to be switches, not to dither around at half-on, when they'll develop hot spots internally and fail orders of magnitude before you'd expect them to.
>> No. 2483 Anonymous
9th January 2019
Wednesday 5:58 pm
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I just want to listen to a class A amp for a while and see if it sounds any better. I've used tube amps before and I do think they sound better with certain kinds of music, but not enough that I would use one all the time.

I don't care if the output transistors burn out faster because I can just order some more from Digikey or whatever.

A book on amp design would also be nice so I have some idea of what I'm doing. But I'm perfectly happy to just blindly follow a schematic.
>> No. 2484 Anonymous
9th January 2019
Wednesday 7:00 pm
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Something like https://www.electroschematics.com/3537/2n3055-24-watt-class-a-amplifier/
The wrong MOSFETs used in linear mode - you won't be replacing them every few weeks, more like 50ms after power-on. Linear ones do exist, they just cost a bit more and are very different architecturally.
That linked design uses classic old bipolar 2N3055s for the power stage - as long as you buy legit ones, they're quite robust, but there are a vast number of knockoffs with implausibly small die, thin heat spreader cases and generally smoke fodder.
>> No. 2485 Anonymous
9th January 2019
Wednesday 8:07 pm
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I was more looking for firsthand accounts from people that have actually built one, but at this point anything is helpful.
>> No. 2486 Anonymous
9th January 2019
Wednesday 10:52 pm
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Can't really help you, then. Good hunting!
Having just completed my first Silicon Carbide FET job - if you're looking to make your life even harder, and want to waste time and money, they'd make ideal class A power devices. Otherwise, probably best stick to good old silicon or vacuum.

>> No. 2473 Anonymous
5th November 2018
Monday 8:03 pm
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I want to replace my 50 gallon cold water tank in the loft. Do I need a 50 gallon one or could I get away with 40 or 25?

My house settings:
one bathroom
shower that runs off mains
22 gallon (approx) hot water tank
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>> No. 2474 Anonymous
5th November 2018
Monday 9:09 pm
2474 spacer
Can't see why the 40 wouldn't be just fine.
>> No. 2475 Anonymous
5th November 2018
Monday 9:15 pm
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In theory, a 25 gallon tank should be fine for a cold water only system. Personally, I'd replace like-with-like just to be sure. If the mains supply to your house has weak or inconsistent pressure, you might need the extra capacity.
>> No. 2476 Anonymous
6th November 2018
Tuesday 5:44 pm
2476 OP
Just ordered the 40.
>> No. 2477 Anonymous
10th November 2018
Saturday 3:48 pm
2477 OP
Got the bitch in there now. Only had to spend another 30p on some olives.
>> No. 2478 Anonymous
10th November 2018
Saturday 4:34 pm
2478 OP

>> No. 1531 Anonymous
5th October 2013
Saturday 8:30 am
1531 spacer
Do you lads fancy a pumpkin carving contest?

You've got just under four weeks to work on your designs and hone your carving technique.
57 posts and 9 images omitted. Expand all images.
>> No. 2468 Anonymous
18th October 2018
Thursday 1:44 pm
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1 rVwicojch6CTSE-pVK7kNw.jpg
That time of the year again lads.

Winner can annoy purps into making the winner the /uhu/ banner and get one free shitpost.
>> No. 2469 Anonymous
19th October 2018
Friday 2:05 pm
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I made a very small OwO pumpkin this year as I was feeling lazy. Any candle in it goes out almost immediately due to it not being big enough and it's already starting to crumple.
>> No. 2470 Anonymous
19th October 2018
Friday 2:58 pm
2470 spacer
Apparently cutting the hole from the bottom of the pumpkin and carving it from there rather than the top helps them last longer and not fall in on themselves, as does coating the insides in lemon juice after hollowing them out. Also, if you put cinnamon on the sides after when you go to put a candle in it it'll smell like the flat of that girlfriend that left you.
>> No. 2471 Anonymous
19th October 2018
Friday 4:13 pm
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what part of "lazy" don't you get?
>> No. 2472 Anonymous
22nd October 2018
Monday 9:00 am
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My mate made a harambe one 2 years ago

>> No. 2463 Anonymous
17th September 2018
Monday 3:50 pm
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Is it possible to fit a domestic toilet with flush button on the floor? Think Arriva Trains style. I've had a look online and not seen anything.
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>> No. 2464 Anonymous
17th September 2018
Monday 4:16 pm
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You can get remote flush pneumatic buttons

and floor mounting it doesn't seem an impossibility. If you want a longer tube, you may need a larger swept volume in the button, but I think you can have what you desire.
>> No. 2465 Anonymous
17th September 2018
Monday 4:42 pm
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I can't see why you couldn't rig one up to your doorbell if you really wanted the mechanics of them are really quite simple.
>> No. 2466 Anonymous
17th September 2018
Monday 4:57 pm
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Put one under the toilet seat that acts on release so when you stand up it flushes.
>> No. 2467 Anonymous
17th September 2018
Monday 5:01 pm
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But not everyone wipes sitting down.

>> No. 2324 Anonymous
23rd September 2017
Saturday 7:03 pm
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How much would a little skip like this cost to hire?
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>> No. 2325 Anonymous
23rd September 2017
Saturday 7:39 pm
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Dunno. You should probably call the number on the side of the skip.
>> No. 2326 Anonymous
23rd September 2017
Saturday 7:57 pm
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skip prices.png
Here's my research from the last big project I managed.

The one in your photo is probably an 8-yard.
>> No. 2460 Anonymous
9th September 2018
Sunday 1:40 am
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Can we make a sport out of seeing how much it is possible to verload a skip?
>> No. 2461 Anonymous
9th September 2018
Sunday 2:06 am
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You couldn't measure it by pure weight or volume alone since people could cheat via extremely heavy materials or by resting some huge blimp on it. I would recomment the natural log of mass*maximum cross-section.
>> No. 2462 Anonymous
9th September 2018
Sunday 3:03 am
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The Chinese would dominate it, if their salad bar pisstaking is anything to go by.

>> No. 2452 Anonymous
18th June 2018
Monday 10:51 pm
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Sorry to do this chaps but I need some ideas. I have been tasked with setting up vertical dividers on a concrete block wall, to support some tall & rather heavy objects. My manager doesn't have any ideas and I have only a few hundred pounds to spend on approximately 40 dividers.

Currently the best idea I have is as shown in the picture - a bunch of steel tubes cut to length, inserted into a wall flange socket such that the tube is perpendicular to the wall (pointing outwards at the person browsing the stock). I'm thinking each divider will consist of one tube at around knee height and another at shoulder height (with nothing connecting the two because the elbows and additional tubing would cost too much). Some kind of safety cap on the ends of each tube of course.

My main worry is that they simply won't support the forces one them, as the longest would need to extend around 130cm from the wall. Would greatly appreciate any better suggestions. I am aware that pre-made industrial solutions exist but they run in the hundreds of pounds for each rack.
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>> No. 2455 Anonymous
19th June 2018
Tuesday 1:10 am
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Have to agree. If you're not qualified to install something that could potentially hurt people then don't let yourself get talked into doing it. Not just for your own sake but out of essential moral principle.
>> No. 2456 Anonymous
19th June 2018
Tuesday 8:29 am
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Another vote for 'fuck, no!'
a) block walls just aren't rated for loads like that, things will just tear out
b) it will be your fault.
>> No. 2457 Anonymous
19th June 2018
Tuesday 10:24 am
2457 spacer
further - especially long unsupported poles at knee and shoulder height. Customers are going to be battering into those, swinging on them, climbing them, even without your heavy stock hanging on them. Without some vertical support at the non-wall end, this reeks of failure.
>> No. 2458 Anonymous
19th June 2018
Tuesday 6:50 pm
2458 spacer

As other lads have said, don't take on the responsibility. Get something off-the-shelf which will come with a certificate telling you exactly how much weight you can put on it.
Shop around industrial racking suppliers to try and find something suitable.

This seems to be the sort of thing you're looking for:
>> No. 2459 Anonymous
19th June 2018
Tuesday 9:51 pm
2459 spacer

Ok I have taken everyone's replies into consideration (much obliged), and modified the plan to this.

I will also hire someone else to do the installation to make sure it's secure. Only ordered the parts for two dividers for now. I'll give them a stress test after installation and if all seems ok we'll go ahead with the remainder.

This is great and I appreciate the link, but
a) they don't extend far enough, and
b) the quantity needed makes the total cost about 4-5 times what we have to spend

>> No. 2438 Anonymous
10th March 2018
Saturday 5:26 pm
2438 A damn good rodding
Feeling pleased with myself - bought rods, cleared blockage, didn't fuck up, didn't get covered in shit. Heart-stopping moment as the vile bolus of horror hurtled through my open pit and headed downstream in one foul dollop, but it didn't seem to hang up on anything.
Now for a really satisfying dump. Life is tolerable.
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>> No. 2439 Anonymous
10th March 2018
Saturday 5:36 pm
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I once got someone around to clean my blocked drains - I saw the largest mountain of poo I have ever seen. The dude just dealt with it. I wanted to hug him.
>> No. 2442 Anonymous
10th March 2018
Saturday 8:37 pm
2442 spacer

What, after you'd made him shower and change his clothes first?
>> No. 2444 Anonymous
10th March 2018
Saturday 9:54 pm
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>I saw the largest mountain of poo I have ever seen. The dude just dealt with it.

When you clean drains day-in-day-out, chances are that he has dealt with much bigger poo mountains before.
>> No. 2448 Anonymous
11th March 2018
Sunday 4:07 am
2448 spacer
No doubt about that at all - but I had never seen a metre cubed plus pile of poo before and I never want to again. What surprised me was it didn't look anything like what you see at the sewage or water works - it was just a huge fucking pile of poo under a manhole cover in my garden.

Have the utmost respect for the people who do these kind of jobs - there is a funny little man at work who spends the entire day going to each floor and cleaning out the gents shitters; I try to make sure I say hello every time I see him.

>> No. 2384 Anonymous
4th February 2018
Sunday 4:02 pm
2384 Kitchen Bollocks
I was gifted for Christmas, separately, both a power drill and a magnetic knife rack. Please no comments about my parents' combined attitudes to radicalising their daughter.

My idea was to attempt to mount the rack on the side of my kitchen cupboard, as the kitchen is tiny and I have a mortal fear of drilling my walls. It comes with some assembly bits like rawl plugs and two types of screws.

Will this work? What kind of screws do I need? Should I try to drill into the sides of the cupboards (quite thin, IKEA units) at an angle to sit the screws in? Will they need a plug or can they just sit in the cupboard if they're wood screws? I've weighed the knife rack with all the knives I intend to use on it and it'll probably come out to under 1kg. I think that should be fine.

My dad's not picking up his mobile and the only person more afraid of the combination of me + power drill than you is myself. Thanks in advance, lads.
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>> No. 2441 Anonymous
10th March 2018
Saturday 8:00 pm
2441 spacer

I'm not him nor have I used one of those monstrosities, but since it's a whetstone that does the angle for you, I can say that it'll razor sharpen a dull knife in a minute or two, and you can absolutely rescue dinged knives by grinding away on a coarse stone for a while then gradually using finer stones. That might take a while, depending on how fucked the knives are, but probably no more than 20 minutes for civilian damage, and it's quite a zen process.

There are still knife blokes who seem to appear in cookware shops on certain days who will regrind your knives proper. I don't really understand who they work for or why they only charge 2 quid a knife, but if you run into one get him to work his magic.
>> No. 2445 Anonymous
11th March 2018
Sunday 12:37 am
2445 spacer
I use steak knives in the kitchen. Never need sharpening.
>> No. 2446 Anonymous
11th March 2018
Sunday 2:19 am
2446 spacer
Why does he go to all that effort to clean it up and then not sharpen it properly?
>> No. 2447 Anonymous
11th March 2018
Sunday 2:46 am
2447 spacer

Most people are morons on some level.
>> No. 2449 Anonymous
11th March 2018
Sunday 8:22 am
2449 spacer
He does, I'm guessing you skipped to the end and were seeing the comparison to a cheap un-sharpened knife.

>> No. 2395 Anonymous
28th February 2018
Wednesday 12:21 pm
2395 dead maplin
It's been a shadow of its former self for a long while, and I guess getting destroyed by Amazon. But will miss it.
23 posts and 1 image omitted. Expand all images.
>> No. 2423 Anonymous
1st March 2018
Thursday 9:01 am
2423 spacer

True enough, I'd just have to think of a better name for it.

Semiconductor transfer technician.
>> No. 2424 Anonymous
1st March 2018
Thursday 5:33 pm
2424 spacer
> isopropyl alcohol
I've bought it off ebay before no problems, although only a little 100ml bottle.
>> No. 2425 Anonymous
1st March 2018
Thursday 7:24 pm
2425 spacer

RS do free next day delivery on aerosol cans.

>> No. 2426 Anonymous
2nd March 2018
Friday 8:27 am
2426 spacer
I worked there for a long time, and in a different timeline I might still have worked there. I always said they were circling the drain.

Management were a complete set of tossers, and to make matters worse they took on a load of plonkers from Comet when they shat the bed. Within a decade it went from a handy shop to get a 15p battery connector, to a poorly staffed rip-off where the same connector would cost you £1.69, if they even had it in stock. Too much reliance on min/max stock levels and margin over volume, which drove away near enough all the trade business.

Still, I'm going to laugh when it turns out they'd been siphoning off the pension scheme too. I might go and visit my old boss just to laugh at him about it.
>> No. 2450 Anonymous
16th March 2018
Friday 7:06 am
2450 spacer
Just saw this in El Reg -


Fucking hilarious.

>> No. 2388 Anonymous
16th February 2018
Friday 12:17 pm
2388 spacer
Any tips on getting this ear wax out?

I tried with a toothpick but it didn't work.
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>> No. 2390 Anonymous
16th February 2018
Friday 1:40 pm
2390 spacer
You should be able to remove the rubber part just by pulling on them, that will make it easier to clean.
>> No. 2391 Anonymous
16th February 2018
Friday 1:44 pm
2391 spacer
Manky bastard.
>> No. 2392 Anonymous
16th February 2018
Friday 3:05 pm
2392 spacer
Given that it was ingested within the first week of having them, that's not very cost effective.

I tried, they aren't removable unfortunately

Come on teenlad, I know you've saved it to your wank folder for future pleasure. Along with the infamous chair and plughole.
>> No. 2393 Anonymous
16th February 2018
Friday 3:12 pm
2393 spacer
Try cotton buds?
>> No. 2394 Anonymous
16th February 2018
Friday 3:12 pm
2394 spacer
Hands up who thought OP's image was a selfie by a cyborg snail.

>> No. 2365 Anonymous
19th January 2018
Friday 1:12 pm
2365 Shelves
After googling around a bit, all the custom length shelving I can find is about 30cm depth maximum. That's not a great help if I want to put things like a printer on them, is there anywhere that'll just sell me some nice planks cut to order, or cheaper mahogany-finish deeper than 30cm?
12 posts omitted. Expand all images.
>> No. 2379 Anonymous
19th January 2018
Friday 10:29 pm
2379 spacer
I think I'll rely on slightly overestimating the lengths I need then cutting it down on location, I have the tools and it's safer than presuming all my preliminary measurements were accurate.
>> No. 2380 Anonymous
20th January 2018
Saturday 1:19 am
2380 spacer
>I have at least two long spirit levels and quite a lot of pencils

I think you're on the right path. Spirit levels are gods own implement. Promise me you won't start drilling or doing anything until the wall is covered in pencil gridlines; then you'll be fine mate.
>> No. 2381 Anonymous
20th January 2018
Saturday 1:26 am
2381 spacer
No m7, the B&Q machine they have is a monster and designed to cut 2.4m x 1.2m boards - every cut is square, its not done by hand.
>> No. 2382 Anonymous
20th January 2018
Saturday 1:37 am
2382 spacer
Turn up at the machine with the exact measurements, pay the cutting fee, it is more accurate and quicker than anything you can do at home.
>> No. 2383 Anonymous
28th January 2018
Sunday 11:52 pm
2383 spacer
Most B&Qs will cut for free so long as you don't want a silly amount of cuts.

>> No. 2346 Anonymous
9th December 2017
Saturday 4:01 pm
2346 Garage w/ no mains, recommendations
I'm renting a garage with no mains power. I'd like a cheap and cheerful way to light it.

I could go the whole hog and buy a generator, but I've read that's noisy and expensive.

Ideally I'd like some sort of LED light, but I'm worried that it won't be powerful enough to light a fairly large garage. I don't know much about lighting, lumens, etc.. The benchmark I want is to be able to do basic maintenance or read a book with the garage door closed.

A related but less important thought is that I'd also like a heater. This wouldn't need to be much at all, just enough to take the chill off if I'm out there for a couple of hours.
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>> No. 2347 Anonymous
9th December 2017
Saturday 4:23 pm
2347 spacer
For comparison, a normal 60 watt bulb puts out 800 lumens and a 100 watt bulb puts out 1600 lumens. That would be a reasonable range for adequate lighting of a single garage.

Your choice will depend on how much battery life you need. If you'll only be in there for a few hours at a time, I'd suggest a rechargeable work light. This will give you a broad area of bright light, like an outdoor security light. The one at the link below will run for three hours on a charge at a maximum brightness of 1400 lumens. If you'll be in there a lot, I'd suggest adding a leisure battery, which will give you much longer running times. For working on the car, I'd also suggest a headlamp, which will give you good lighting in awkward corners.

For heating, you've got a choice between propane and paraffin. A propane heater is generally a bit cheaper to buy and heats up faster, but you have the inconvenience of taking your gas cylinder to be refilled. A paraffin heater can be a bit smelly and you occasionally have to fiddle about with mantles and wicks, but it's less faff to refuel. In either case, you'll want to make sure that your garage is very well ventilated and I'd suggest a carbon monoxide alarm.

>> No. 2348 Anonymous
9th December 2017
Saturday 5:25 pm
2348 spacer

Thanks. I had just stumbled on worklights when I noticed your post. I was about to pay the same price for a 750 lumen light. I went for your suggestion instead.

I probably won't be out there for any more than two or three hours a time.

About gas heaters, would some kind of little camping heater be suitable? Something like:


I might as well put a carbon monoxide alarm in there ahead of time, as it seems like something that should be in a garage anyway.
>> No. 2349 Anonymous
9th December 2017
Saturday 9:41 pm
2349 spacer

Those little camping heaters run on disposable butane canisters, which will get quite expensive over time. They're a reasonable choice if you just need to take the chill off occasionally. You can buy a second-hand paraffin heater for about £50, which would be a more economical choice if you're in the garage a lot.
>> No. 2364 Anonymous
27th December 2017
Wednesday 1:03 pm
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Just a note to say the worklight was spot on. Good illumination and it even has a little battery power readout.

>> No. 2350 Anonymous
23rd December 2017
Saturday 9:07 pm
2350 UHU/101 crossover?
Thanks, previous owners.
To be batshit enough to paint mains sockets, and slack enough to leave the plug in while you do it, takes a special kind of person...
All the light switches and sockets here have been painted many, many times, and the switches don't click, they sort of slump in a really unconvincing way that makes a chap think of fire.
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>> No. 2359 Anonymous
25th December 2017
Monday 1:52 am
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What middle class shops do you go to? I can get some from train station crackhead for cheap.
>> No. 2360 Anonymous
25th December 2017
Monday 8:58 am
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Coloured ones? I doubt it. Even at Wilkos a red one is a tenner. And if you're painting a room you'll likely need two or three.
>> No. 2361 Anonymous
25th December 2017
Monday 12:30 pm
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Why would you go to Wilkos? Do you like paying more money than you have to?
>> No. 2362 Anonymous
25th December 2017
Monday 2:25 pm
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Gives me a right stonker it does. I go grocery shopping at Shell garages for the same reason.
>> No. 2363 Anonymous
25th December 2017
Monday 2:59 pm
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Sorry but what part of the country is Wilkos expensive? And where else can you get coloured sockets? Don't tell me B&Q or something is cheaper, and I've never seen anything other than a white one in poundland etc.

>> No. 2344 Anonymous
9th December 2017
Saturday 3:16 am
2344 spacer
Best way to clean my monitor?
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>> No. 2345 Anonymous
9th December 2017
Saturday 10:40 am
2345 spacer
Isopropanol and a soft cloth. Clean (preferably pure) water will work OK. Don't use any kind of detergent, because it'll strip off the anti-reflective coating.

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