I was always under the impression that connecting bridge rectifiers in parallel would lead to one diode hogging all the current and leading a chain reaction of failures. Is there times that paralleling bridge rectifiers is legitimate or was this just a poor design choice?
I'm looking for some replacement components for the PCB on my Ideal 61-747 multimeter.
As an appliance technician I was not careful and grounded out a HV component in a microwave and blew a couple caps and possibly one of the PTC fuses.
As the components are from China, I was unable to find information for a western equivalent to the WMZ12A PTC on the board.
Do any of you have any ideas? Also, where do you source your components?
Hi,
I'm looking for creative project ideas that use at least 4 logic gate ICs and are useful in daily life. The project should be practical and feasible to build on a breadboard within a few weeks.
Any ideas or insights would be greatly appreciated!
Thanks in advance!
I'm noticing a lot of used USB PD chargers starting to show up at surplus and electronics recycling stores and they usually have a wide variety of voltages from 5 to 20V available.
Are there some USB PD Trigger boards that are known to be
-
bad and faulty
-
good and reliable?
I plan to use one such trigger to replace a 9V battery for my garage's electronic lock so it will be constanly plugged in without supervision, others to provide 12v@4A power to various routers around the house and of course for my own electronics projects when prototyping
I have a few old TVs at home that I use, right now I've got them rigged up to one of those annoying digital to analog converter boxes that we had to buy when TV went digital here in the USA. It bugs me that I've got to use the remote which I keep losing when those big oh-so-satisfying uhf and vhf dials are right there on the tv. And I'd also like to chuck the box if possible it's one more thing I've got to precariously balance on top of my TV. Does anyone make an INTERNAL digital tuner that I could replace my analog tuner with? I'd love to be able to use those dials. Or one with buttons for later TVs would be great too. I'd really love to find some kit or something I can mount inside my TV case and would work with just dials or buttons, i can still keep the remote but i like having the option of just pressing a button on the tv to change channels or the volume or mute or whatever.
Hello, I'm looking for comments on when to use a Passive or Active Probe o-scope probe.
Thank you
Hey everyone! I am honestly sick and tired of my cheap breadboards (sourced from Aliexpress and other questionable sellers). The contacts are always unreliable and they make building and debugging circuits a gigantic pain. Are there any brands or sellers that you would recommend that are based in the EU? Thanks in advance!
I want to build a doorbell for my house using an ESP32. I want it to send me a WhatsApp message when someone rings the bell, which is already resolved. The issue now is with the speaker. I bought a 3W, 4 ohm speaker, and I'm using PWM for the output pin of the ESP32 with an amplifier using a 2N2222A transistor, powering the speaker with 3.3V. The problem is that I wanted to handle everything with 3.3V, but I don't think it's possible to achieve a loud enough sound for a doorbell. There is a possibility of using a 12V power source for the speaker, but I prefer to avoid that for reasons that are not relevant here. Basically, my question is what kind of speaker should I use for a doorbell? How much power is needed to be heard from 10 meters away, for example? The 3W speaker sounds like turning the volume of a mobile phone to the maximum and playing a YouTube video. This is my first time working with audio, and I'm a bit lost.
Hey, so im currently trying to build an monitor controller. I want to swap between different inputs and different outputs, with each output having its own volume poti. I figured I should first unbalance the signal to get away with cheaper faders, that do not have 12 pins, if there even are any.
I´ve found this to "convert" the signal.
and luckily found just the other end of my build on the same page.
So the plan was to just chain them together and then im fine.
Just like, ehem, this:
ofc everything twice because its in stereo.
My power gets supplied by this
I already build it, twice.
Naturally, because im a pro straight onto the stripboard.
But as it failed now on the breadboard.
My TL072 get pretty damn hot, I can smell them a little and (I think) the oscilloscope tells me they are self oscillating. At least its defenetly not putting out what Im putting in.
Some questions besides the problem:
1)
Do I have to put a load at the output? I straight up put the oscilloscope at the output, no thing else. Could this lead to the heatup? Though Id find it unlikely as there are so many IC out there running idel, every second board would pop.
2)
Do I have to wire one end of the poti to ground for it to work?
Ok I might have found another mistake. I thought I wired the Poti in my INA217 Mic-Pre to ground, so I did that here as well. But I just noticed that I actually didn´t (in the INA217 circuit). Though when I look that up they all ground one pin...
3)
Is Maybe the PSU is just not smooth enough and the ripple cause the IC´s to fail?
4)
Is it bad to only run one half of the IC? Because I did just that on the breadboard.
Im actually quite sure I build the first half, the input stage, on the breadboard before going to the strip board.
Which worked, so I jumped straight to the next stage. I´ll build the first stage again while waiting for answers to proof that again.
Also a picture of my circuits will follow.
Many thanks in advance! Hey, so im currently trying to build an monitor controller. I want to swap between different inputs and different outputs, with each output having its own volume poti. I figured I should first unbalance the signal to get away with cheaper faders, that do not have 12 pins, if there even are any.
I´ve found this schematic here to "convert" the signal. and luckily found just the other end of my build on the same the plan was to just chain them together and then im fine.
Just like, ehem, this:ofc everything twice because its in stereo.My power gets supplied by this already build it, twice.
Naturally, because im a pro straight onto the stripboard.
But as it failed now on the breadboard.
My TL072 get pretty damn hot, I can smell them a little and (I think) the oscilloscope tells me they are self oscillating. At least its defenetly not putting out what Im putting in.
Some questions besides the problem:
1)
Do I have to put a load at the output? I straight up put the oscilloscope at the output, no thing else. Could this lead to the heatup? Though Id find it unlikely as there are so many IC out there running idel, every second board would pop.2)
Do I have to wire one end of the poti to ground for it to work?
Ok I might have found another mistake. I thought I wired the Poti in my INA217 Mic-Pre to ground, so I did that here as well. But I just noticed that I actually didn´t (in the INA217 circuit). Though when I look that up they all ground one pin...
3)
Is Maybe the PSU is just not smooth enough and the ripple cause the IC´s to fail?
4)
Is it bad to only run one half of the IC? Because I did just that on the actually quite sure I build the first half, the input stage, on the breadboard before going to the strip board.
Which worked, so I jumped straight to the next stage. I´ll build the first stage again while waiting for answers to proof that again.
Also a picture of my circuits will follow.
Many thanks in advance!
I am trying to read a small remote with an arduino and IR sensor. I can get the arduino to read my tv remote but I get unknowns for protocol and value when I try to read the small remote. Reddit and my googling has lead me to I probably need a oscilloscope or logic analyzer. Could someone explain how I would use either or both to figure out the remotes IR signal so I can transmit that signal and if you have recommendations for which models I should consider buying, I would really appreciate it.
EDIT: I wired the button up wrong... But all the tips in the comments should help every thing run smoother in the finished project
I'm kinda new to electronics and everything I heard made it sound like MOSFETs were just bigger transistors. Then I started a project that need a transistor that is fast and can handle more power so I bought some MOSFETs. Once they arrive I built a circuit I saw in a video and am getting REALLY weird behavior. I hooked up a LED and turned on the power supply and the LED immediately lit up dimly and the button I hooked up did nothing. But touching the positive leg of the LED causes it to fully light up and slowly dim down once I let go. It must be something to do with the capacitance of my body since I made sure I was fully insulated. For reference I am using a IRF3205 MOSFET I got from Aliexpress.
And heres a quick and crappy circuit diagram:
I'm looking at devices from the 1980s that have chips with military part numbers. Is there a cross-reference to standard part numbers? If I'm lucky, I'll find the part number on Google, but most of the time it's just junk sites.
For instance, I have a chip labeled "SM-A-915719", which turns out to be the same as NSN 5962-01-102-7613 which is also M38510/40001BQC (where M38510 is a prefix common to all chips), which is described in . From that, I recognized the chip as the Motorola 6800 microprocessor.
There must be a document somewhere that explicitly says "SM-A-915719 is the MC6800" and so forth, but I can't find it. Does anyone know how to identify these chips without a Where's Waldo adventure?
I am repairing an old HP oscilloscope and the hard drive needs to be replaced or recovered. Anyone know where I can either find the recovery disk software or the disk itself? I reached out to Keysight but I don't have high hopes. According to the manuals I found the model is so old that it wont support any upgrades to the software due to ram limitations and I think the motherboard might not support ram upgrades XD
Thanks in advance for any help!
If I have an eight-pole connector listed at two amps, is that for the whole connector or two amps max on each pole?
Here is an example connector: