Thursday, October 22, 2015

PC Sound Card Oscilloscope

Dear DAPJ: I would like to buy a Microphone and either #1. an oscilloscope or #2. sound oscilloscope software. For hobby purposes, I would like to sample different sounds & view the various sound waves studying the amplitudes & frequencies. Do you have a product that would meet these criteria?

Thank you. Respectfully,

Mail from MH - US

No i dont sell anything. But here are a few suggestions.

OsciPrime is an Open Source Android high speed data acquisition hardware platform and Android oscilloscope application. (2015)

Simple solution for only sound - Zelscope buy only software. Test out out, buy if you like it. You need a computer.

Buy a PicoScope or if you want to build one Bitscope

Study also
delabs (2009)

Thursday, October 08, 2015

Usage of Schmitt trigger NAND Gates

I have a question about your "Long Duration Timer" circuit, del20017 found here ..Long Duration Timer Clock

Long Duration Timer

You have labeled U1 as a 4093. A 4093 is a NAND with schmitt trigger inputs, yet the schematic displays only NAND gates without schmitt trigger inputs. Which device did you intend? A 4093 or a 4011 (Quad 2 input NAND gate).

Mail from PB

Where mixed signals are at input both analog and digital 4093 is better. Like digital inputs after going thru a long cable the square wave gets deformed, 4093 refines it to a digital square again. When interfacing with input devices like switches 4093 is better as it works as a noise filter. Generally 4093(++) is an upgrade to 4011, i think it is a pin to pin replacement .

Digital Timers Counters and Clocks

In the circuit above U1C and U1D have to be schmitt trigger nands. U1B also needs a bit of wave cleaning. U1A can be 4011.


The 4093 gate didn't embed properly .. so I have attached it this time. thankyou for your prompt reply. I understand the need for schmitt triggered inputs as you have pointed out. I guess for completeness I was also pointing out that the schematic should show the NAND gates with schmitt triggers as shown below.

2 input NAND with schmitt trigger 4093.

Reply from PB

Sunday, October 04, 2015

How bently nevada proximity sensor works

The following was submitted on February 20th, 2007 at 08:07AM (PST).
Subject:  how bently nevada proximity sensor works

Mail from UM

You have asked the same question in many forums. I found that while searching on the internet. That means you still have doubts.

How bently nevada proximity sensor works

Microwave and RF radiates energy. - You know when a magnet is moved near small nails it make them Move ! If you make an DC electromagnet it make the nails move again.

But when you keep swapping the polarities, That is with an AC supply it generates a field or radiates an energy. Right from the Toy generator with magnets to the Sun it is the same. The highest form of sun is it radiates photons.

RF is nothing but a Magnet rotated at high speed which is called frequency. This energy can cause food to cook in your microwave oven or a proximity sensor to gauge the gap. It even helps people when the have a sun bath.

I have seen even an old Analog Joystick of a Machine has this induction method to position objects. Study Links below for helping you understand better.


Applications of electromagnetic induction - An eddy current is a swirling current set up in a conductor in response to a ... and to provide the necessary energy required for the motor to do work.

Design of an Eddy-Current Proximity Sensor using a Two-Coil Planar ... .However these proximity sensors are not conducive to scaling to conventional integrated circuit levels. This is because most conventional eddy current