Turn your Digital Voltmeter into an Inductance and capacitance meter. Page 1. Page 2. Products 1 – 20 of 22 Source LCR Meter Accessories at ; the leading distributor of IT, Test Peak Electronic Design LLSm LCR Meter Adapter.
|Country:||Bosnia & Herzegovina|
|Published (Last):||3 February 2012|
|PDF File Size:||20.9 Mb|
|ePub File Size:||20.33 Mb|
|Price:||Free* [*Free Regsitration Required]|
If not, then match the value of the resistor R7 to make shape of the signal as close to square wave as possible. Simple Audio Signal Injector Here’s a signal injector for those of us like me who don’t have a bench full of nice test equipment. There is a way to check out the duty cycle at the collector of Q1.
Arduino Prototype uses all standard through-hole components for easy construction, two of which are hidden underneath IC socket.
Check out all five ranges. The circuit includes an auto ranging as well as reset switch and produces very accurate and stable readings. The meter is a perfect addition to any power supply, battery chargers arapter other electronic projects where voltage and current must be monitored. Inductance Meter In-Use The resolution of the analogue meter obviously limits its performance, but I generally use it to just ensure I am in the right ballpark while winding coils or picking from the junk box.
The output waveforms can be both amplitude and frequency modulated. Connect a battery and a DVM digital volt meterput a known inductor in the LX position then adjust the potentiometer until you get the anticipated reading on the DVM.
Inductors with iron cores, high permeability ferrites, or with large amonts of shunt capacitance cannot be measured accurately. More resources from carbonzit Resource icon.
The Circuit The circuit’s operating principle is that if you make a pulse width proportioal to inductance, and keep the pulse frequency and amplitude constant, and then pass the pulse through a low pass filter so that only the average voltage comes out, the resulting DC voltage is proportional to the inductance. Media New media New comments Search media. More precise measurements I do with a resonance bridge. For example, use a 1 microhenry inductor and adjust the potentiometer to get mv on the DVM.
You might have some trouble getting the thing to calibrate if the switching thresholds on your 74HC14 are very different from the one I used, so you might have to change the resistance in the osicllator or the capacitor in order to claibrate the circuit. If you use a DIP, your life will be much easier.
If you find the voltage to be very low, say under a volt, then this points to a wriing error, a problem with the 5V regulator or the battery, a damaged 74HC14, or you are using a very low resistance voltmeter. Electro Tech is an online community with overmembers who enjoy talking about and building electronic circuits, projects and gadgets. Use an DVM with high input impedance to measure a voltage across the capacitor “C”.
FOA – LC Connector adapter
This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils and inductors. The switch S2 is in position “L”. The pulse frequency is set by a schmitt trigger oscillator composed of a feedback resistance 2k pot and 3. It also analyzes transistor’s characteristics such as voltage and gain.
Here are some things to check when calibrating: Here is the unit measuring a 33 uH commercial RF choke.
meer To my surprise, it actually worked just fine, 1K in series was sufficient to allow a useful calibration and didn’t overload the drive capabilities of inductsnce last gate in the package. The pulse width that is proportional to the inductance is made by drving the unknown inductance through a resistor and connecting the resultant sawtooth waveform to the input of another schmitt trigger which, because of the sharp switching action on its output that results from its hysteresis, provides a nice rectangualr pulse.
I took this circuit from this page on the QRP Homebrew site and made some modifications to it, described below. Articles Top Articles Search resources. Click here to register now. It works 6689 an oscillator whose frequency is determined by the RC components R I calibrated my unit for uH, as this is the meeter I am generally most interested in, and it gives direct-readings on the uA scale of the meter.
It is an irreplaceable tool for troubleshooting and repairing electronic equipment by determining performance and health of electrolytic capacitors. In the one I built I used a pair of alligator clips soldered to stout wires a couple of cm long.
I happned to have the 74HC14 in an SO package so I soldered it onto the metalized side of a prototyping board.
If not, you may have too much inductance in the leads to LX or have connected LX to a noisey ground point. A switch S2 is used to configure the measurement circuit. This circuit provides DC output voltage on the clamps X6, X7, and this voltage is directly proportional to the inductance of Lx. Replacing a 4 pin leaded inductor with a 2 pin Started by adapted Yesterday at