Hi all,
Thought I'd ask for help in this forum as part of my efforts to get to the bottom of this annoying issue.
I run a small home studio, in a room with a air conditioning unit. Brand is Gree, it uses an inverter and rated at12000 BTU I believe.
Whenever the AC is cooling, it seems to be...
Hi everyone,
I'm new in here. I designed a controller card project and the card can switch some devices with relays, dfplayer mini to play sounds from sdcard, external bluetooth music player card is connected to the circuit. cd4066 used for audio switching between dfplayer and Bluetooth audio...
Firstly im not saying this is a problem, i just want to know what exactly causes it.
When you unplug a charger its still making the transformer pitch sound but it’s instead going high and high in pitch until a buzz is heard and then the sound stops. This lasts 10 seconds. What causes it?
I have a Belkin phone charger and I have noticed that every time I disconnect the phone, It makes a series of strange noises, a high pitched one, a low pitched one and then it continues making a high pitched sound. I know that the transformer is making these sounds but, why does it make that...
I've had a DSO-2250 9-bit/250MSps/60MHz scope for a decade, bought "new", and it's always had a large ripple voltage (about 1/3 of a division) overlayed on any signal. The ripple sometimes made the DSO barely usable. At some stage I put a filter on the USB cable inline with the power; this...
Hello good people,
I need help. I'm posting a schematic of an ultra low noise amplifier. It is to be powered by batteries. For that reason, I need a stable DC solution in the place of R4 resistor. I was proposed to achieve that by using another JFET and an integrator circuit, but I am not...
Hey guys, new to this forum and would really appreciate your help :)
I am making an alarm which will trigger a buzzer from about 30ft away and a noise which will help you find the object that you had lost.
In perspective I am making a lost and found type of device. Whilst there are similar...
I have neighbours from hell with music heard in the street 50 meters down the road, the authorities do nothing so I thought natural law and technology would help.
Other forums give solutions, but miss full instruction, so I thought I would find technical forums and ask qualified people for there...
I'm a little rusty on noise problems from switching power supplies. And I hope someone can offer some advice. There's this new system which relies on a small +12v smps. This system has a separate controller board mated with a motor controller using board connectors. And the 12v smps connects...
Alright, my question is pretty simple to ask but perhaps rather difficult to solve.
I am modelling in LTspice a channel of previous design and analysing various noise figure across the channel.
Currently I am using the stock resistors supplied in LTspice. I was wondering if there is a way to...
Hi all.
I recently purchased a (obviously) second hand CRO oscilloscope.
It worked fine for a couple of days, I was just getting used to it.
Then one day, I left it on for 10 mins or so with both traces active on screen.
A while later, I heard this high frequency hiss, so I switched it off.
The...
Hi!
In order to cool a telcom device I am using 4x 12Vdc fans from Delta Electronics (the exact type is FFB0412VHN-F00). The fans have a 3-wire interface and I operate them by sending PWM pulses at their power supply wire. The pulses are generated from a PIC-microcontroller and are "converted"...