Thanks for the info guys. I guess my question pertains specifically to what appear to be the variable filters on the diagrams. All filters I'm familiar with need some reactive component, like an inductor or capacitor. Is some technique used to build the reactive elements in the the chip...
I am curious to know how the RF front end of a Wifi receiver works. From my understanding, most RF receivers have to use networks of various oscillators, mixers, and filters to select a given frequency and remain insensitive to undesired signals at different frequencies, and I suspect that WiFi...
I'm working on a school project that requires me to build a RF oscillator that is able to be started and stopped at about 100kHz. Ceramic or crystal oscillators would be good because of their tiny size, however, the high Q factor creates a problem. So my question was, can placing a resistor in...
Hello everyone,
I'm working on a project that requires me to demodulate an NTSC composite video signal into an RGB form. Despite having read a book and visited numerous websites detailing how this is performed, I am still confused. First, it seems that the colorburst signal is not in phase (or...
I've been looking for a good formula to calculate the inductance of a multilayer solenoid within about 10% accuracy or greater. I've used several formulas derived from Wheeler's formula, as well as a few online calculators, however, my results seem to differ wildly depending on what formula or...
Okay, thanks for the information guys. It isn't my own CNC machine, it's at a metal shop in my town. I took the file I had to the guy and who basically said the same thing, that the file is put in the machine and then scaled based on a known dimension of some part of the cutout.
I'm working on a project that requires me to use a CNC metal cutter. I'm using LibreCAD to design the thing I need to have cut (it's a radio chassis). The wiki doesn't really offer much besides a general how-to-use, and after playing around on the program I'm wondering two things. First...
With regards to the 4-QAM; I'm not sure if it's an unrelated discussion but the idea behind this circuit was to try and send two audio channels, a left and right, by QAM to a receiver. A 4-QAM device would have to be used at a much higher frequency to send any sort of "good" sound if used...
A digital process hasn't been ruled out yet, especially given that the output of the 100kHz oscillator is a square wave. I am still testing various methods of getting this phase-shift signal.
Sorry about that. I've succeeded in making an oscillator, and I have also succeeded in using an integrator as a phase-shift circuit, however, due to the level of attenuation it creates I'm looking for a better option, which was why I asked about the circuit configuration used in FM receivers...
Sorry to resurrect this thread, but I recently ran across a phase-shift design used in phase discriminators for FM detectors that uses a capacitor in series with a parallel LC circuit. The original design can be found here: http://www.ajay.keckist.edu.np/ec2/fm_detectors.pdf After running a...
It's for a project that requires me to send and receive an FM signal at about 50 MHz. I was planning on using FET transistors for all the low powered oscillation, mixing, and amplifying stages, and possibly the transmitter output and audio output stages. The transmitter doesn't have to be very...
Wouldn't the stray capacitance be in parallel with the crystal, not series (and the crystal is a series-cut).
Here's a schematic of the oscillator I'm using (attachment). It's a butler oscillator designed for series-operating crystals. And the crystal I'm using is a 100 kHz crystal, but...
Thanks for all the input guys. On the topic of crystal oscillators, is it the load capacitance or the shunt capacitance that is supposed to be placed in series with the crystal? So far I've been using the data sheet's specified load capacitance of 12.5pF, but the data sheet specifies a shunt...