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24
Stickied postModerator of r/diyelectronics

Hi everyone,

Today we've reached 10k subs on r/DIYElectronics! That's ten thousand people tinkering with electronics at home, asking questions and helping each other out. I think that is really awesome.

For new users here, r/DIYElectronics started out over two years ago as a place for challenges with electronics at the DIY level but has moved to a platform to share progress, ask and answer questions about personal electronics projects.

Thanks to everyone who has contributed over time by posting their projects, helping other people out or just by asking a question!

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5

I have two systems in a single box using the same cooling system. The cooling system uses it's own independent power source.

I want the cooling to only be on while one (or both) of the system's are powered up so my first thought was just a simple relay but I'm unsure if I can have a single relay hooked up to two different sources.

Any advice?

0

Battery connector is ripped of from main board. How this should be fixed? I see no traces coming to those pads. Is there any?

Thanks for any help!

Hi-res picture:

https://imgur.com/2rOtbm7

5

Imgur Link https://imgur.com/gallery/5HX4ww5.

Apologies in advance if this is not the correct sub. Trying to repair an alarm clock I recently dropped off my bedside table. It landed on the end with the tuning/volume knobs and the am/fm toggle. The play button on top is how the tape function is enabled. Now my problem is even with all play button not pushed down it automatically starts spinning and trying to play the tape. Any ideas of where to start looking and possible solutions to this problem would be much appreciated.... do not enjoy starting my day with the ear screeching alarm sound rather than the radio. Thanks in advance

5

Electronic timer+breaker? Not sure what I got here https://imgur.com/a/u4afpqj

My halfway senile dad tasked me with installing this timer for him. I have NO IDEA how!

Way back when my dad simply did it himself, but his mental decline means he isn't capable anymore. It upsets him each time he sees the timer and once again realizes he can't do it anymore. So I'm going to plug away at this till I get it right.

I googled the digits on the timer and found many circuit diagrams of how it can be wired. But I can make no sense of it at all.

Any guidance would be appreciated. Even just a link to a webpage explaining the diagrams would be nice. I'm keen on learning more about this especially seeing as this might be the last thing me and my dad get to spend time on together.

2

Alot of times i want to do a project i just find it annoying that i don't have the parts i need, and sometimes have to wait like a month to get the parts. Do you guys have tons of components laying around? if so how did you get them, did you salvage them or have you brough them all yourself?

2

This is a logic diagram of what I want to build (this uses two 4-bit comparators linked together only due to the limitations of the software used).

This is an axle counter for a miniature railway, that uses infra-red sensors with Schmitt triggers for the inputs. What it's used for is to detect whether a train is in a section which has a set of points/railroad switch.

What happens is: The flange of the wheel goes past AA1 and blocks it, then AA2 and blocks that, and then unblocks AA1, and then AA2. This adds 1 to the first counter in AA and turns the AA relay output off. This basically means "Hey, there's a train in the section". As the axle does the same thing to the next counter, the two counters are compared and when they equal each other, the AA relay output says "Hey there's no train in this section anymore".

The reason for the three different sections and the and gates is that it has to count the train coming into the section and count it coming out of either the main road or the secondary road. Some of the sections don't need and gates but putting them in means that the boards are universal depending on how we wire them.

I'm looking for some help converting this logic diagram into an actual schematic. I'm not really sure where to start as it needs to use a 12V supply. I already know which sensors we're going to use so we have to build the schematic around that.

Based in the EU, if that helps anything. I realise this is really specialised, and poorly described, but I'd appreciate any help anyone can give me.

5

I'm building a project and a project workstation with several sensors and some accessories. I have a 24v 6A Meanwell power supply for the whole box. I have components that need power:

  • 9v (component tester 500mA)
  • 5v (sensors and pots max 1A)
  • 5v USB workstation light and Arduino nano for status display
  • 3.3v (sensors max 150mA)
  • 12v (sensor max 250mA)
  • 24v (soldering iron)

I've been testing with the little Chinese blue boost buck converters but haven't been impressed. Any ideas or maybe some multi channel DC power step down converter that I can buy or maybe build?

9

In many common "legacy" projects, the power is provided by a 9v wall wart driving a 7805 and associated filter caps. This made sense in the 70's - 2000's when 9v wall warts were the most commonly available DC source. But today, does that still make sense? Why not just use a 5v USB charger source and a filter caps?

I do know that you cannot drive a 7805 with 5v - so we can skip that part of the explanation :)

1

Hello,

I've been tinkering around and I've been trying to set up a system with my speakers.

I have a song I wrote with 8 separate recordings. Each recording is a different instrument. I'm trying to set it up so that a touchscreen or physical sliders can be adjusted by me to increase or decrease the volume of each independent sound file.

I'm doing this for fun, as a learning experience. I just need some advice to point me in the right direction. Do I want the recordings all stored on an sd card and the sliders linked to an arduino/raspberry pi and adjusted that way? I would want all 8 recordings playing at the same time even if volume is 0 to ensure syncing.

Thanks

5

So I have USB Type-C ports on a board and I need to assemble the prototypes by hand. The connectors have two rows of contacts, the first being an exposed SMT line I can roll-solder, but the second is a row of THT pins under the connector and I'm stumped on how they work. Diagram here:

https://www.hirose.com/product/en/download_file/key_name/CX70M-24P1/category/Drawing%20(2D)/doc_file_id/141189/?file_category_id=6&item_id=04800304000&is_series=

The holes for the pins are the size of a small THT via and the pins only extend ~1/4 of the way through the board.

I can't figure out how to solder them. Do I paste and reflow, in which case I should worry about the solder wicking away? Do I hand/wave solder them, and worry about the solder not wicking far enough? They claim to be easily reworkable as a result of this feature but I'm struggling to understand how they're supposed to work. The only alternative in Type-C connectors is a second SMT row under the device, which I imagine being substantially worse.

5

I have no idea where to start but I want to learn how to make a voice changer even though I know they have them available thru various makers. I want to make two things for two costumes. I want to make my voice sound like it's coming from a helmet (boba Fett but I can provide the accent) and layer the sounds of Darth Nihilus over my actual voice so I can talk but have also the garbled sound.

5

I have some 2N7000 and I like them a lot. But some module I have and need to sue uses reverse PWm logic in that when the pin is high it is off and on when low.

I was thinking I'd just feed the PWM into a p-channel mosfet to inverse it. and I'd like the logic level P-channel the same size or package as 2N7000.

is there any easier way? do they sell single Not gate chips?

2

So I'm a professional tattooer and I'm building a tattoo power supply based on the Spaulding and Rogers "toaster" My question is, I will have several capacitors in the build , 2200, 100, 10, and 1. All wired parallel. Why are they there? The wiring plans I have calls for them but I want to understand what their purpose is. My thoughts are I have a transformer outputting 16 vac into a bridge rectifier making 16vdc. Then I use a rheostat and I can control the voltage. But why have the capacitors? Thanks in advance!!!!

Edit: changed series to parallel

2

So I ran across a facebook store selling this electronic poster of goku but unfortunately it looks like it might be a scam but I was wondering how I might go about building one of my own if possible? Thanks in advance. https://youtu.be/ts7mFJnmV80

3

I have a few old phones laying around and wanted to do something with them. I removed the battery, attached wires to the +/- in order to get the power to the outside. Put the battery back in and done!

The charging of the phone is done thru USB, so now it's a "smart battery pack".

I cheap female USB and/or some other connector and you have a universal battery back out of a throw-away phone.

It has 1600+ mAh, not overly impressive, but should power my headphone amp for quit a while.

Q. anyone know if I can add more phone batteries to this by simply connecting to the same line?

There's 3 connectors, if I add a 2nd battery thru those same connectors, would that cause a problem? The phone would take longer to charge, but would have power longer.

Would there be a heating problem?

9

tl;dr What hex code should I send to this device to increase the volume?

Hey folks, I'm working with a speakerphone called the Jabra 410 which offers an HID interface. I'd like to increase the volume programmatically. Here's the report descriptor:

Report Descriptor: (length is 273)
    Item(Global): Usage Page, data= [ 0x0c ] 12
                    Consumer
    Item(Local ): Usage, data= [ 0x01 ] 1
                    Consumer Control
    Item(Main  ): Collection, data= [ 0x01 ] 1
                    Application
    Item(Global): Report ID, data= [ 0x01 ] 1
    Item(Global): Usage Page, data= [ 0x0c ] 12
                    Consumer
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0xea ] 234
                    Volume Decrement
    Item(Local ): Usage, data= [ 0xe9 ] 233
                    Volume Increment
    Item(Local ): Usage, data= [ 0xe2 ] 226
                    Mute
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x03 ] 3
    Item(Main  ): Input, data= [ 0x02 ] 2
                    Data Variable Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x05 ] 5
    Item(Main  ): Input, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Main  ): End Collection, data=none
    Item(Global): Usage Page, data= [ 0x00 0xff ] 65280
                    (null)
    Item(Local ): Usage, data= [ 0x01 ] 1
                    (null)
    Item(Main  ): Collection, data= [ 0x01 ] 1
                    Application
    Item(Global): Report ID, data= [ 0x02 ] 2
    Item(Local ): Usage, data= [ 0x01 ] 1
                    (null)
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0xff 0x00 ] 255
    Item(Global): Report Size, data= [ 0x08 ] 8
    Item(Global): Report Count, data= [ 0x20 ] 32
    Item(Main  ): Output, data= [ 0x02 0x01 ] 258
                    Data Variable Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Buffered Bytes
    Item(Local ): Usage, data= [ 0x01 ] 1
                    (null)
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0xff 0x00 ] 255
    Item(Global): Report Size, data= [ 0x08 ] 8
    Item(Global): Report Count, data= [ 0x20 ] 32
    Item(Main  ): Input, data= [ 0x02 0x01 ] 258
                    Data Variable Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Buffered Bytes
    Item(Global): Report ID, data= [ 0x04 ] 4
    Item(Global): Usage Page, data= [ 0x30 0xff ] 65328
                    (null)
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x20 ] 32
                    (null)
    Item(Local ): Usage, data= [ 0x97 ] 151
                    (null)
    Item(Local ): Usage, data= [ 0x2b ] 43
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x03 ] 3
    Item(Main  ): Input, data= [ 0x23 ] 35
                    Constant Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Local ): Usage, data= [ 0x2f ] 47
                    (null)
    Item(Local ): Usage, data= [ 0x21 ] 33
                    (null)
    Item(Local ): Usage, data= [ 0x24 ] 36
                    (null)
    Item(Local ): Usage, data= [ 0xfd 0xff ] 65533
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x04 ] 4
    Item(Main  ): Input, data= [ 0x07 ] 7
                    Constant Variable Relative No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x09 ] 9
    Item(Main  ): Input, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Local ): Usage, data= [ 0xff 0xff ] 65535
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x01 ] 1
    Item(Main  ): Feature, data= [ 0x22 ] 34
                    Data Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x07 ] 7
    Item(Main  ): Feature, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Usage Page, data= [ 0x40 0xff ] 65344
                    (null)
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x17 ] 23
                    (null)
    Item(Local ): Usage, data= [ 0x1e ] 30
                    (null)
    Item(Local ): Usage, data= [ 0x09 ] 9
                    (null)
    Item(Local ): Usage, data= [ 0x18 ] 24
                    (null)
    Item(Local ): Usage, data= [ 0x20 ] 32
                    (null)
    Item(Local ): Usage, data= [ 0x21 ] 33
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x06 ] 6
    Item(Main  ): Output, data= [ 0x22 ] 34
                    Data Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Usage Page, data= [ 0x30 0xff ] 65328
                    (null)
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x9e ] 158
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x01 ] 1
    Item(Main  ): Output, data= [ 0x22 ] 34
                    Data Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x09 ] 9
    Item(Main  ): Output, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Main  ): End Collection, data=none
    Item(Global): Usage Page, data= [ 0x0b ] 11
                    Telephony
    Item(Local ): Usage, data= [ 0x05 ] 5
                    Headset
    Item(Main  ): Collection, data= [ 0x01 ] 1
                    Application
    Item(Global): Report ID, data= [ 0x03 ] 3
    Item(Global): Usage Page, data= [ 0x0b ] 11
                    Telephony
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x20 ] 32
                    Hook Switch
    Item(Local ): Usage, data= [ 0x97 ] 151
                    Line Busy Tone
    Item(Local ): Usage, data= [ 0x2b ] 43
                    Speaker Phone
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x03 ] 3
    Item(Main  ): Input, data= [ 0x23 ] 35
                    Constant Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Local ): Usage, data= [ 0x2f ] 47
                    Phone Mute
    Item(Local ): Usage, data= [ 0x21 ] 33
                    Flash
    Item(Local ): Usage, data= [ 0x24 ] 36
                    Redial
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x03 ] 3
    Item(Main  ): Input, data= [ 0x07 ] 7
                    Constant Variable Relative No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Local ): Usage, data= [ 0x07 ] 7
                    Programmable Button
    Item(Global): Usage Page, data= [ 0x09 ] 9
                    Buttons
    Item(Local ): Usage, data= [ 0x01 ] 1
                    Button 1 (Primary)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x01 ] 1
    Item(Main  ): Input, data= [ 0x02 ] 2
                    Data Variable Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Count, data= [ 0x09 ] 9
    Item(Main  ): Input, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Usage Page, data= [ 0x08 ] 8
                    LEDs
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x17 ] 23
                    Off-Hook
    Item(Local ): Usage, data= [ 0x1e ] 30
                    Speaker
    Item(Local ): Usage, data= [ 0x09 ] 9
                    Mute
    Item(Local ): Usage, data= [ 0x18 ] 24
                    Ring
    Item(Local ): Usage, data= [ 0x20 ] 32
                    Hold
    Item(Local ): Usage, data= [ 0x21 ] 33
                    Microphone
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x06 ] 6
    Item(Main  ): Output, data= [ 0x22 ] 34
                    Data Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Usage Page, data= [ 0x0b ] 11
                    Telephony
    Item(Global): Logical Minimum, data= [ 0x00 ] 0
    Item(Global): Logical Maximum, data= [ 0x01 ] 1
    Item(Local ): Usage, data= [ 0x9e ] 158
                    (null)
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x01 ] 1
    Item(Main  ): Output, data= [ 0x22 ] 34
                    Data Variable Absolute No_Wrap Linear
                    No_Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Global): Report Size, data= [ 0x01 ] 1
    Item(Global): Report Count, data= [ 0x09 ] 9
    Item(Main  ): Output, data= [ 0x01 ] 1
                    Constant Array Absolute No_Wrap Linear
                    Preferred_State No_Null_Position Non_Volatile Bitfield
    Item(Main  ): End Collection, data=none

Report page #3 does a lot of stuff and #1 will give me lights, but I can't for the life of me figure out how to do volume control.

Here's a link from Jabra talking about their HID spec: http://developer.jabra.com/site/global/sdks/web/documentation/index.gsp

0

Hello Reddit,

I purchased this small space heater for inside my 3d Printer enclosure. I'm going to have it hooked up to a relay and Arduino to turn off and on once the inside temperature reaches say 35 degrees Celcius. The issue is the heater has a thermal fuse built in that turns off the heater once it reaches a certain temperature. I'm a novice when it comes to electronics so I thought I'd ask some questions first.

Here is a photo of my enclosure

Here are two photos of the heater taken apart.
Pic 1
Pic 2

1) In picture 2, is the thermal fuse the component attached to the red wire? (I only googled this a few moments ago and it appears to be but best to make sure)
2)If I remove this and replace it with a wire, will it operate?
3)What is your expert opinion on me doing this?
4)What are my other options for SAFELY controlling the heat within my enclosure?

Thank you!

1

Hiya! I've got a wireless mouse with a faulty battery compartment. One of the electrodes is partially corroded and I often have to clean off the build up. It's gotten to the point where the battery no longer connects. Hard for me to see clearly but I think the electrode is quite rusted off a bit.

This is my first time attempting to fix an electronic, I think it's a simple replacement of the electrodes or battery compartment.

Any advice on where to shop for replacement parts, how to pick one out, what to test for to make sure this is the problem, installing the replacement piece, etc.?

Thanks in Advance! :)

3

Hello, first off I have very little idea what I am doing, I am pretty laymen. Just a simple photographer that wants a really bright light. I am attempting real hard to drive these LEDS such that they are dimmable from 0-100% duty cycle via arduino PWM signal OR tlc59711 which Arduino will be controlling..

How cna I drive these at the ~650mA constant current it needs and yet still dim with PWM? I was told a linear voltage regulator converted to CC is what I need. but I am not sure how to do that or if it is right.

5

So I have one spare generic LED fog light made for cars, because the other got damaged during shipping. It has the main fog light but it also has an angel eye ring of LEDs around it too. They each run on 12 volts.

I'm wondering I can use a portable phone charger, wire it up to a step up converter and power the lights? My plan is to use a micro usb breakout, wire that up to the step up converter, and then wire that up to an on-off-on switch for the lights. Am I doing anything horribly wrong?

Edit: I knew I was forgetting something obvious lol. I didn't even think to check if the portable chargers could provide enough power. The lights use 20 watts which is double what the chargers can provide, so this isn't going to work.

6

I am sure this has been asked before but I am not having any luck finding what I am looking for. I wanted to print out a wind turbine design and have it spin a small dc motor to generate some output. If I can Id like that to charge a portable phone battery. Is there any circuitry I can use to regulate voltage from a non constant source?

3

I am starting to design a LiPo battery balancing system. It will utilize a simple passive/discharging balance topology for each cell. I would like each cell to have its own discharging circuit and microcontroller chip hooked up as a slave to a master controller. I would like to use the Arduino IDE to program the chips so I can make this open source and easy for people to adapt to their own battery.

I am hoping that someone with more knowledge on the Attiny or Atmel chips can let me know what chip will be best/easiest to use for this application.
* DIP package design
* Few additional components to run the chip
* Communication pins to master
* Arduino IDE compatible

Thanks in advance for any help. I will try to answer any questions as quickly as I can. I'm hoping to make something very cheap and valuable for people in the DIY battery bank community.

3

I'm getting ready to build a keyboard and I understand there's some SMD soldering to do. I have the Hakko FX888D. Is there anything else I should buy to do the SMD work? Very new at this.

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