The DIY-ers corner

[Jet Badger]

The washing machine went down on the weekend so I had to take a look at it since it's good 5 years out of warranty. God bless washing machines that give out error codes.

The door lock mechanism connector was sizzled, which I found strange as it was the door switch pin, through which no substantial current should pass, that was the fault. Tinkered around with the whole lock which seemed to be fine and scraping the ashes off the contacts proved to be sufficient to get the thing working. Probably temporarily, but working.

It's alive! Hooray for clean clothes!

 

[AOS-]

How's that even happen with a locking mechanism?

 

[HammerRacing]

good morning everybody.
just two of my finished projects.
-wireless Ps3 button box ,built from a arcade fight stick
-hydraulic handbrake .

regards, kingklingeling

View attachment 128622

May I ask... how do you get the handbrake / button box to communicate with the PS3? Cthulhu board or other?
If I made an analog handbrake (POT or Loadcell), how would the PS3 "know" ... do I need a PCB between the POT and the PS3 or can I just connect the POT via a USB cable to the PS3?

 

[Jet Badger]

May I ask... how do you get the handbrake / button box to communicate with the PS3? Cthulhu board or other?
If I made an analog handbrake (POT or Loadcell), how would the PS3 "know" ... do I need a PCB between the POT and the PS3 or can I just connect the POT via a USB cable to the PS3?

Yes, you would need a controller board by all means. Hooking up a potentiometer directly to an USB cable and plugging it in would likely cost you a PS3.

If you wanted an analog handbrake on PC, you could use anything from a butchered joystick with an analogue axis to a dedicated controller board like Bodnar's or any other. Not sure if there's any point in having an analogue handbrake on PS3 because from what I remember, atleast in GT, it can't be mapped to an axis - it's only either on or off. But if you really wanted one, I'd suggest using a regular DS3 and hooking your contraption to one of it's thumbstick axis as there aren't really many options here.

Oh, and if you wanted to use a loadcell you would also need an interface circuit to convert the loadcell output into what the controller could understand.

 

[Jet Badger]

So we have a college assignment over these weeks to design and make an electronic thermostat that would switch on two fans and ultimately turn a system off as the temperature rises. First time in 1.5 years I got enthusiastic about this whole education thing as we finally got something other than dry theory and unrelated subjects. Spent some time over the weekend routing the PCB with which the teacher was fairly impressed as someone's first attempt. I can say that certainly petted my ego.

I'm sure there's more room for overall improvement but I think I got it fairly compact (86x60mm). Not yet sure just how successfullly it'll turn out, but surface mount components for the win.

 

[AOS-]

PCBs fascinate me, but because I'm PCB-illiterate, it's a ton of mumbo jumbo to me.

Would it be too much work if I asked to describe which part acts as the switch and what component tells the thing to shut off when the temperature rises?

 

[Jet Badger]

PCBs fascinate me, but because I'm PCB-illiterate, it's a ton of mumbo jumbo to me.

Would it be too much work if I asked to describe which part acts as the switch and what component tells the thing to shut off when the temperature rises?

Not at all. 👍

It's basically a non-inverting comparator (it compares two voltages and triggers output if the voltage on the (+) input is higher than that in (-) input) and a voltage divider - several resistors of one which is a thermoresistor that changes it's resistance depending on temperature. There 3 sets of those in this case (except for the thermoresistor - there's one) for the 3 stages of operation.

I'm pretty bad at explaining things but in this pic you basically set the trigger/gate voltage with R1 and R2 at which you want to have output when the signal in (+) from the thermoresistor reaches it.

Since the fan we want to control is a relatively high-power device, we need to use a relay for it and we also need to trigger the relay coil but the comparator only outputs like 20mA or so and the coil needs around 40mA to close - not enough. We must put a transistor between them to act as a switch that can handle a bigger load. There's also a resistor between the comparator output and transistor base to limit current to 20mA(let's say) so we don't burn up the comparator.

That's pretty much the principle. Not that I actually understand very much of what I'm talking about here.

 

[AOS-]

That still doesn't make a lot of sense to me. I'm looking at that and I don't even know how to determine which direction a voltage is going, and why each labeled part is there for.


duhhhh

 

[Jet Badger]

That still doesn't make a lot of sense to me. I'm looking at that and I don't even know how to determine which direction a voltage is going, and why each labeled part is there for.


duhhhh

Ahh, one thing I forgot to note is that the thermoresistor in the schematic is supposed to connect to the X4 terminal, hence why it's not there itself.

I've quickly redrawn a single block of the thing here, it should much easier to understand. You can see the thermistor in the top left corner and the relay in top right.

 

[W3H5]

For a school project today I built a portable solar oven from junk laying around the office. Had a short test and it got pretty hot, tomorrow I will attempt to bake chocolate bananas with my students.
I also knocked up a quick phone stand from the coroplast left over from my solar oven.
I'll get some picks of the oven tomorrow when it's in action.

 

[Robin]

Does anyone know what I can mod an old DVD player into?

It's more in the shape of a VCR and totally toast but I want to use the enclosure. I've seen people on the net use them for a HTPC but this one wouldn't be big enough to fit the PSU in so it would look a mess.

Any thoughts?

 

[W3H5]

I always, always forget to take photos of my builds and diy jobs but just now I remembered to photo my diy effort. So using an old coat hanger and a cable tie I present to you The Shem-O-Matic Scooter Cruise Control.

The fitting is tight but has just enough movement to slide down into the brake when the throttle is pulled and keep the throttle pinned in position. This should help with my hypermiling efforts.

Next up could be a small wind shield made from an old oversized helmet visor I have in the yard.

 

[sesselpupser]

Does anyone know what I can mod an old DVD player into?

It's more in the shape of a VCR and totally toast but I want to use the enclosure. I've seen people on the net use them for a HTPC but this one wouldn't be big enough to fit the PSU in so it would look a mess.

Any thoughts?

You could maybe use an external PSU? Or if you come across a laptop with a broken LCD that isn't worth fixing you could swap the guts over?

As for the rest, the power supply out of a DVD player might be good for a simple electronics bench supply (pretty sure they at least do 12 and 5V, just not with a huge amount of current I guess), the tray itself could be a simple plotter axis... I was going to make a plotter out of DVD drives but, well, I haven't yet. That was years ago, I should get that back out. Also if the display is a VFD take a look at EEVblog's recent video about VFDs, I think they look really nice so you might be able to use that for something.

 

[Robin]

You could maybe use an external PSU? Or if you come across a laptop with a broken LCD that isn't worth fixing you could swap the guts over?

As for the rest, the power supply out of a DVD player might be good for a simple electronics bench supply (pretty sure they at least do 12 and 5V, just not with a huge amount of current I guess), the tray itself could be a simple plotter axis... I was going to make a plotter out of DVD drives but, well, I haven't yet. That was years ago, I should get that back out. Also if the display is a VFD take a look at EEVblog's recent video about VFDs, I think they look really nice so you might be able to use that for something.

I could use the PSU externally and run the cables in but it would just look slightly messy. It's a pity that PSU's are still the same size they have always been (apart from really specialist ones). I think the power supply of the DVD player is fried which is why it's dead! I'm sure I can find a use for the rest of the stuff, I'm already going to harvest the quality capacitors from it.

I've wanted to make use of old displays on set top boxes, I will have a look into the blog, thanks!

 

[sesselpupser]

@Robin. Oh, I could've sworn someone made an external PSU that just had the one cable, something like the one Apple used for the G4 Cube, which plugged in to a PCI slot cover which had all the cables broken out on the other side... I must be imagining things. How about a PicoPSU? That way you only need 12V coming in so you can use an off-the-shelf power brick, albeit a pretty powerful one.

 

[Jet Badger]

So I sort-of finished the thingy. Not that it works as it should though.

I spent all evening troubleshooting it. Well, I either burnt some of the components or I have a lot of resistor values wrong. Soldering the SMD components was a lot easier and a lot more fun that I expected aswell, so atleast there's that.

 

[sesselpupser]

I just got a couple of new toys in the post...

Clockwise from the top left:
- Pololu A-Star 32U4 microcontroller
- ESP8266 wi-fi serial TX/RX module
- MPU-9150 accelerometer/magnetometer/gyroscope

The 32U4 and MPU-9150 are destined to become an EDTracker unit possibly integrated into my headphones if I can, the ESP8266... I have no idea yet, I just wanted to see what all the fuss was about and see if I can program it with the 3v3 TTL cable I got for my Raspberry Pi.

 

[Dennisch]

I made these for a giant barbecue my parents have bought for my brother in law.

2mm sheet metal, long M10 bolts cut to size for the spokes and some scavenged pipe cut to size for the 'bearing' .

Sheet metal beaten into shape on the bottom of my welding gas cannister.

 

[Jet Badger]

Figured making a little nightstand from old desk parts would make me feel less useless.

Quick sketch, 45cm tall

And the thing after 3 hours, somewhat in shape. Still can't decide which way around I like it more.

I'll try to find some stuff to cover up the sawn-off edges, some feet for extra support and make some drawers over the weekend maybe. Maybe.

 

[AOS-]

I like it with the legs pointing out. This way, it "presents" the bottom cubicle. Plus, it reveals the surface of that middle section a lot more.

 

[Jet Badger]

I like it with the legs pointing out. This way, it "presents" the bottom cubicle. Plus, it reveals the surface of that middle section a lot more.

I was thinking the same, plus it would provide better support with to-be drawers open.

 

[Pagey279]

I decided to give myself a project for the next month or so. I was looking for a TV stand but couldn't find any to the measurements I wanted so I'm going to build my own.
Solid oak (the texture I used was the closest to oak I could find!), with copper cladding struts to break it up a bit. The top corner shelf bit will be for the Tivo box, with DVDs/blu-rays stored to the left.
The shelf down will be for my PS4 (no backs to the corner shelves for better cooling) with my games to the right and the bottom shelf for my PS3.

I might play around with some LEDs and light it all up if I can find a way to hide the wires.

 

[W3H5]

Looke up a way to keep cables and wires neatly in my draw. I've had them hung on hooks until now. Found a pocket-type thing that looked easy enough to make so I set about it with a roll of duct tape and a pipe cleaner.

 

[AOS-]

but couldn't find any to the measurements I wanted so I'm going to build my own.

This is my excuse for spending the extra money on building things I could simply buy.

There's also the excuse that you can't a product in the most idealistic colour or materials to match your own furniture or decor. Custom building lets you make things exactly the way you want them!

 

[sesselpupser]

So I've made some improvements to my PC/sim desk thing:

- Removed two monitors because I wasn't really using them
- Added cable management channels to the underside of the main desktop bit (this would make more sense if I could show you, but it's too dark to photograph)
- Reapplied my cable ties from display and power cables that used to run at the back of the desk (until I ditched the other two monitors) to the cables that now run inside the desk, which is a lot more comfortable because now I don't have cables brushing my hands when I type or brushing my legs when... Well, they were always brushing my legs and it was annoying.
- Turned the small table my PC and PS3 are on 90 degrees. This might not sound like a big deal but since my new mATX PC fits on the short length of the table (if you get what I mean), there's no longer a ton of wasted space at the back to collect dust that gets spat out of the back of the PC. There is, however, quite a large gap between my PS3 and PC now which is just going to collect dust, in fact it's already started doing exactly that.

And last night I had an idea for a little mod; part of my purging of unnecessary crap from my PC area involved removing the Sony 5.1 home cinema box I wasn't using - since I just use headphones to avoid disturbing people - so I thought "Hey, I bet I could fit a Raspberry Pi and a Homeplug device in there...". I've just taken the lid off to have a look, ended up removing the DVD drive to test the receiver still works without it - it does - and then tried plugging my Pi into the front USB port to see if it can supply enough current which it can. So now I have to:

- Find a spare Homeplug I can use and see if it works when embedded inside a different device, I'm a bit skeptical of this because I think they create a ton of noise so putting one within the shield of a different, possibly quite sensitive device seems... Well, totally stupid. I could try fashioning a shield within the case but then there's still its own AC power line which will have to be routed through the case to the AC in point on the power supply board, which is on the corner nearest to the amplifiers. I'm sure that'll be fine, though. In theory if I wire it up in parallel to the AC entering the receiver it should be no different to the receiver and a Homeplug sharing a power strip, so... Yeah.
- Blank off the front USB port (I've never, ever used it anyway and I've had this thing for ten years now) and reroute it to the internal Pi.
- Blank off the front audio in 3.5mm jack socket (I've also never used that), convert the internal wire to a 3.5mm jack plug and plug it into the Pi
- ???
- Plug it all in and enjoy wirelessly streamed, hugely sub-par quality stereo audio through five channels and a subwoofer.
- Get sick of that, add a cheap USB DAC and pick up a more modest and appropriate 2.1 speaker set...

 

[Jet Badger]

I replaced the double 3.5mm TRS jacks on my headphones/headset with a single 4-pin one. My laptop only has a single combined audio jack anyways, and the extra mic cable just gets in the way. Fascinating, I know.

It even says Sennheiser. Lol. An order of magnitude improvement in audio quality right there.

I also have some project plans for the nearest future. Drew the schematic and laid out a preliminary PCB for an Arduino ATmega8 based soldering station controller using one of those knockoff HAKKO 907 handpieces. Gonna get into it as soon as I receive the parts.

 

[kikie]

My new G27 ish steering wheel.

35cm OMP wheel and extended shifter peddles. Much better than the standar 28cm G27 rim.

 

[TexRex]

View attachment 392633

I decided to give myself a project for the next month or so. I was looking for a TV stand but couldn't find any to the measurements I wanted so I'm going to build my own.
Solid oak (the texture I used was the closest to oak I could find!), with copper cladding struts to break it up a bit. The top corner shelf bit will be for the Tivo box, with DVDs/blu-rays stored to the left.
The shelf down will be for my PS4 (no backs to the corner shelves for better cooling) with my games to the right and the bottom shelf for my PS3.

I might play around with some LEDs and light it all up if I can find a way to hide the wires.

Did anything come of this?

 

[kikie]

Does this count?

Grew these myself (not sure if this is the correct expression) ................................................. by accident. It's, kind off, a DIY thing, isn't it?

 

[Pagey279]

Did anything come of this?

Sadly not, I got a new job and have been away from home for training since that post. The training has finished but with 10-12 hour days I haven't got much time to do anything!