1. Luiz Fernando Vieira

    What is the frequency changing when I change the W?

    Hello, I assembled a circuit that is a crossed-out circuit using MOSFETs where I'm working with oscillators with an order of phantom capacitance and an inductor with nano, and I left these values fixed without using .step param in LT Spice. I used the `.step param` method on W to see the...
  2. D

    High-frequency amplifier using bipolar transistors

    Could someone please help design a cascode amplifier with these parameters? Frequency range: 200 kHz to 20 MHz Input signal voltage: 10 mV to 1 V Power supply voltage: 5 V to 12 V Power consumption: up to 100 W And if possible, please also include the calculations showing how to achieve this...
  3. K

    How to Achieve 0.1 Hz Resolution from 0 to 10 kHz Using STM32 Timer?

    Hi everyone, I'm trying to generate output frequencies from 0 Hz to 10,000 Hz using STM32F407VET6 with Timer2 in Output Compare Toggle Mode. The timer clock is 84 MHz. I need to achieve: 0.1 Hz resolution up to 10 kHz Ideally, also support 0.001 Hz resolution at lower frequencies The...
  4. W

    How to Reduce Noise When Measuring 20MHz Frequency Using Relay

    Hello everyone, I'm currently making a test machine for testing (voltage, frequency) PCBs. There are 5 test points on PCB where I need to measure frequency 20MHz. So, I'm using relay to switch around test point and connect to the probe of my oscilloscope (Keysight DSOX1202a). I've found out that...
  5. salhi

    Finding the cutoff frequency of regulator

    Let the following transfert function : C(p) = 0.5926 \frac{1+1.205p}{1+0.4233p} = K \frac{1+a \cdot \tau p}{1 +p \cdot \tau p} with a = 2.848, \tau = 0.4233, K = 0.5926 the marge of phase of this corrector is 28.7° i want to find the cutoff frequency of this correct, the answer was already...
  6. C

    [SOLVED] Occasional High frequency interference

    I have an AMW monitor F199B that occasionally shows a high frequency interference signal on the display screen. Have replaced the BLM1700M10112 board with no change in the behavior. The remaining board is an FSP035-1PI01ZT power supply. All the caps have been replaced on the remaining board...
  7. circ8tz

    Technics SU-CH7 - How can I use a normal speaker with this amplifier? It has 4 connections for each speaker (separated High & Low frequencies)

    Amplifier: Technics/Panasonic SU-CH7 This amplifier belongs to an Hi-Fi Audio system (SC-CH7) that originally comes with speakers (speakers with separate highs and lows too, 4 connections in each speaker). It also needed the Tuner unit (ST-CH7L) in order to turn the amplifier on but I was able...
  8. S

    How do I calculate frequncy for wireless module RF96

    I was reading datasheet for module RF96 (datasheet attached), I understand that we have to set register values to set carrier frequency as descrubed on the page 103, this is also described at some other parts of the datasheet like Pages, 13, 53, 77, 88 Formula described to calculate...
  9. D

    PSRR vs Frequency (PSRR + and PSRR -)

    Hi All, I was recently looking at the Texas Instruments datasheet for the lm324. What I was interested in was the PSRR vs Frequency. I am familiar with the PSRR and its relevance, however the figure below I am seeking further clarification. The way I am interpreting the figure, is that the PSRR...
  10. F

    Modify electric fence circuit from 1Hz to about 8Hz output

    Hi! I'm looking to for some input on how to change an electric fence circuit from about 1Hz (standard) to about 8Hz (7.83Hz is my goal). I am not using the fence circuit for livestock - I am amplifying the Schumann Resonance with this circuit and putting it through a Rodin Coil for broadcast...
  11. mouhkramo

    Using Cobra3 basic-unit

    How to add doppler effect to the interface of cobra3 wich came just with gaz law measurement. IS there any alternatives to use those phywe équipements to measure that effect ?
  12. RipX

    High speed frequency divider

    Hi everyone, I am getting ready to build a frequency divider board for a Z80 game console project. I have a 32MHz active crystal oscillator and want to divide down this to produce the following frequencies that will be used across varying components of the project: 32 MHz 16 MHz 8 MHz 4 MHz 2...
  13. oviniciuslara

    How to increase operational frequency to 70MHz in this Colpitts Oscillator?

    Hello everyone, I'm building a radio transmitter with a Colpitts oscillator schema and everything works fine. I built the circuit and tested in the Oscilloscope and with L=470uH, C1=100pF, C2=100nF I created a 549KHz 6Vpp senoidal (with 5v as source), as we can see bellow: Theoretically, the...
  14. J

    FRF resonant frequencies

    Hi, I'm new here and relatively new to signal processing and analysis. My ultimate goal is to find the mode shapes of a system, but I'm currently working on building the FRF before I move into the next stage. When computing H=Sxy/Sxx (cross power spectrum over input spectrum), I'm getting a...
  15. J

    flashing LEDs circuit

    Found this simple circuit on youtube and I'd like to know the equation for how to vary R and C to change the flashing frequency. Also, how to increase the current through the led with 3.3 V battery as power source to maximize brightness.
  16. S

    Active Band Pass Filter - Design Help

    Hi all, I was hoping someone might be able to provide some guidance/point me in the right direction for the below problem: The objective is to design an active bandpass with the following parameters: Centre frequency Fc = 100kHz Bandwith fH -fL = 10kHz So far I have the following: Given...
  17. Adrienboub

    Remove 10ns jitter from a 1PPS signal from a GPS receiver

    Hello everyone, I'm trying to make a very accurate frequency counter. A GPS receiver allows me to have a 1PPS signal that I use as a reference to do my frequency measurement. According to the datasheet this 1PPS has a jitter of 10ns. In short, the more stable this signal, the more accurate my...
  18. MrsssSu

    Produce high frequency square wave

    Hi readers:), When decreasing R1 value, output frequency will increase. However, I get bad waveform when high frequency. How do I get a good square wave (100kHz) using this LM 741 chip that I bought? Simulation is attached below for your reference and modification to the answer :)
  19. V

    Change frequency of PCB

    Hi, I have some speakers I love, they have a PCB RF reciever inside. I bought more speakers but they are a different frequency.. I'd like to change them so they all match but have no idea what I am doing. Can you help?
  20. M

    Increase clock frequency

    Hi, I’m working on a logisim project for university. I need to increase the clock frequency to 16 Hz, but the frequency must be set in the options to 1 Hz. How can I increase the frequency using only a circuit? Thanks for the help.
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