New answers tagged

5

Piezoelectric filters (resonators). These - per marking - are 10.7MHz band pass filters used for FM intermediate frequency (IF) in a typical superherherodyne FM radio receiver. The middle terminal - if present - is a ground connection. Ceramic resonator (Wikipedia)


4

Based on the context this is a current source. Not the most standard symbol for it - most commonly that would be represented by two overlapping circles or an arrow "floating" inside of a circle.


13

That is a current source. It will be a sub-circuit to generate a reasonably constant current through the push-pull output transistor biasing circuit. To avoid cross-over distortion (a discontinuity on the changeover from sourcing current through the upper transistor to sinking current through the lower transistor) on the output the diodes are added to ...


1

A capacitor C charged with u(t=0) = Va follows these equations: An uncharged capacitor C and a voltage source Va in series follow these equations: They are equivalent as they follow the same i-v equations.


3

Your schematic is possibly faulty and you should concentrate on managing the flyback voltage before tackling the actual MOSFET: - A short story So, let's say you have a 100:1 step-up transformer with absolutely no leakage inductance between primary and secondary. When the output voltage is (say) 15,000 volts, the reflected drain voltage will be 15,000 ...


2

A MOSFET transistor should not be dissipating a lot of heat if it works as a switch, has a very low ON resistance (RDS(on)), AND is much faster than the signal that drives it. In this case, the original transistor had about 0.18 ohms or 180 milli-ohms ON resistance, while the primary has at least 2 ohms, meaning if you ran plain DC current through it, it ...


2

I entered the numbers you so plainly showed on the device and got an immediate hit. It is an electronic fuse or Polymer PTC. Here is the link so you can check it yourself: http://www.hr-ptc.com/en/hr250/141-hr250-080.html They have a contact us on the top where you can email them. Try that, Show a picture and state you cannot find a replacement. Be sure to ...


0

The third component is a tuned IFT probably at 455KHz .It is complemented by the orange ceramic resonator .This scheme provides selectivity on the AM section of this multiband receiver. Other tuned transformers and sometimes ceramic resonators tuned usually at 10.7 MHz provide FM selectivity,


2

It's a thermal fuse for safety. It cuts power to something when that thermal fuse heats above the limit.


0

I installed the EC11B15242AF encoders, and they work perfectly. I used a regular soldering iron for electronics. I tightened the encoders to a flat and straight piece of metal, to keep the encoders lined up when soldering. I needed to add spacers to the ends of the shafts (to make the shafts longer by about 1mm), so that the push switch function would work ...


2

It is a HA17431UA shunt regulator chip. Similar to a TL431, Vref = 2.50V. The large chip is probably a motor driver array of some kind. The pins suggest it is for driving a sizable 3-phase BLDC motor.


0

I got the deoxit spray yesterday, and I sprayed all the encoders. I sprayed the encoder housing so the deoxit would work itself inside, and also sprayed the place where the shaft goes into the encoder housing, and operated the encoders. I did fast turns, and also turned them click by click to attempt to clean them. I repeated this 3-5 times. It seems to have ...


1

Power coils radiate heat better when not mating with insulation on FR4 board especially with lower design margins to thermal runaway. PU adhesive with high tensile strength would be used. Resistors tend to be derated 50% when nearby but will also be elevated if lower temps are needed. Caps are already thermal insulators with thin foil and dielectric and ...


14

It is not a capacitor, it's an inductor, and it's not leaking, it is held firmly in place with glue.


6

It's a really common part, or rather was in the days of through-hole technology. A 1.5A 600V bridge rectifier, versions of which were made by most every rectifier assembler in Taiwan, and probably originally GI (a faded memory). We bought a bunch from a company named Tesla in Yugoslavia one time. You can find their current datasheet here. They are probably ...


Top 50 recent answers are included