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This is a basic question, when feeding a waveguide with a coaxial cable, using the inner cable pin to feed the waveguide (without a conector, its feeding directly), but the shield of the cable does not touch the waveguide, will the antenna still work or does affect a lot?
Also, is there...
Thanks for the schematic @fiwi.
Unfortunately according to a rude simulation i made (cant confirm or not), that schematic will not work well. The formulas that calculators provides maybe not work in a circular waveguide?
Anyhow, the schematic on rectangular waveguides is a bit different on...
Thanks for the answer.
That makes sense, rectangular slotted waveguides have a offset from the center.
My big confusion is regarding "half guides´s wavelength" and λ0:
Guides wavelenght for a diameter 97.87mm at 2.44Ghz is 181.9, so half guides wavelenght is 181.9/2..?
λ0 is wavelenght in...
Its been a long time i try to design a antenna. I´m trying to build a circular slotted antenna for 2.44Ghz based on the paper "On the Miniaturazation of Cylindrical Omnidirectional Slotted WaveguideAntennas for Wireless Applications"
According to a paper:
1) It uses a C22 waveguide...
Re: Laptop motherboard short circuit?
Thanks for replaying.
I did not measure the temperature, but sure its >60º..enough to burn my finger if i keep it there more than a few seconds. Thats the only component that gets hot, the others are cold. After a few seconds it starts to smell overheated...
I was using my laptop normally and suddenly it goes off..after that no light in the laptop with adapter or battery (tested with two batteries).
When i plug the ac adapter in the Laptop the LED of the ac adapter gets blinking with a on/off buzzing sound...so it looks like a short circuit in...
The first suggestion works great! It allows to enable/disable Vbias, and i can measure voltage (1.76?) from Vbias pin :)
But unfortunately did not resolve my issue..i followed the schematic on page 18. But it still gives positive numbers, it stables at -4000 (example) but i only get...
I´m testing it in a breadboard, following the datasheet pag18 circuit.
But my main issue is to change the code in the microcontroller (Arduino) to activate VBIAS..
The code i use can be found here (https://arduino.cc/forum/index.php/topic,53063.0.html), the part to write to the ADC:
It makes sense on "converting" the bipolar signal from the amp to match the unipolar signal in the ADC. But before try some of the schematics you gave, i looked in the ADC datasheet and it looks like it has a function (Vbias) that should solve my issue:
So using "Vbias" in the ADC should work...
I think this is a very simple issue, but my knowledge is very limited, so here it goes my issue:
-I´m using ADC to connected to a sensor, with the sensor connected directly to the ADC inputs, i´ve positive and negative values.
-I´ve added a OPA227 OP-AMP to do some tests with the sensor...
Thanks for the advices.
What i need to do is cut the line in PIN 3 to redirect to REF, something like this?
About the resistor in series, is one 2.7K resistor soldered in the pins of the geophone?
Sorry for asking for confirmation, but i had bad examples in the past involving electronic...
Thanks for fixing the link mtwieg.
I measured the resistance on the geophone, from my cheap/non precision multimeter it gave me 374ohm..which is close to the 380ohm from the specifications. About the calculations..i will take some time to do that :)
So while this circuit works, the choice of...