Showing posts with label meter. Show all posts
Showing posts with label meter. Show all posts

Saturday, October 25, 2014

LED Power Meter

LED power Meter circuit is a simple RF detector using diodes to charge a capacitor. The voltage developed across the capacitor is indicated by a multimeter set to a low voltage range. The circuit is soldered together without the need for a PC board, as can be seen in the diagram below and paper clips are used for the positive and negative terminals of the multimeter.

The level power output of an FM transmitter is indicated by the illumination of a LED and the voltage reading on the multimeter gives a further indication of the output.

A digital multimeter may be used but the presence of RF may produce a false reading. Likewise, the radiated energy may upset some analogue meters and you may get full scale deflection on the 15v range as well as the 250v range! But the LED wont lie. It will accurately indicate the RF and you can see the change in brightness as you adjust the coils in the output stage. Some of the cheapest and simplest multimeters will give the best results as they have a low sensitivity and the radiated RF energy will not induce a reading. Even a damaged multimeter can be used, provided the 10v or 15v DC scale is operating.

The reading is not calibrated and does not represent milliwatts output. It is only a visual indication. 
We have designed over 10 FM transmitters for inclusion in the pages of this e-magazine and each one has different features and characteristics. Some are designed for 3v operation, some are for 9v operation, some are stable for hand-held situations and others are designed for high output. The illumination of the LED will range from barely visible to very bright. 

LED Power Meter Parts 
1 - 470R
1 - 100p ceramic
1 - 100n ceramic
2 - 1N 4148 diodes
1 - 5mm Red LED
1 - 2in (5cm) hook-up wire
2 - paper clips
No PC board required
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Friday, September 12, 2014

Track the damage capacitors elco with ESR meter

All technicians must have the same experience that the old models of aircraft generally have several common Elco its dry or down in value, mainly found in many brands of china plane. Eco is dry can cause a variety of disorders that are sometimes difficult to trace or even be able to make certain parts do not work at all, especially if used on a circuit that works at such high frequency SMPS (Switch Mode Power Supply) and the horizontal. Elco dry technicians sometimes make headaches and time consuming when you track the damage.


Many technicians get around this problem by directly replacing all existing Elko, the Elko-regardless of whether Elko is corrupt or not. It is generally quite successful. But sometimes the quality is not good substitutes Elko, so the damaged aircraft back after use for some time. Replace all of Elko is also a problem for yourself if the circuit is improved a lot using Elko. The use of ESR-meter proved to be the most appropriate choice to solve the above problems. We suggest that ESR-meter is a must-have tool for every technician after avo-meter.

Using ESR-meter weve made themselves at a cost of less than 50,000 rupiah we recorded a lot of advantages such as:

  • Elko track damaged by the time more quickly because they do not need to remove the Elko (in-circuit tester) one by one.
  • Elko only replaced damaged
  • Can be used to check the quality of new and used Elko. It is certainly advantageous to utilize part of the former ex-change machine pcb. Sometimes the plane is damaged due to repeated just posted a new Elko was poor quality.
  • Elko that if the check using the ohm-meter sometimes the results are deceptive. Because if you checked with ESR ESR-meter turns his already large.
  • Can be used to check the flyback is short in the primary coil (between the B + with a pin-pin-collectors), def a short yoke, the power tranfo a short primer.
  • To find out if re-chargeable batteries are still good. Re-chargeable battery that is damaged ESR was generally higher when compared to a still good.
  • To keep track of printed lines leaking / short
  • By comparing the capacitors are still good, ESR-meter can be used to check the value of thousands pf capacitor.
Note:
  • ESR meter can not be to find Elko leak or short. Fortunately rare short Elko damage.
  • ESR meter to check the fit only Elko with values ​​ranging 0.47uF and above.
Does ESR it actually?Parameters are generally owned by a Elko understood by engineers is the "maximum working voltage" and "capacitance value". In the real case there are several other parameters such as the "maximum working temperature" (85 or 105 degrees C) and "ESR" (Equivalent Series Resistance).Unless the practice is capacitive in Elko also has the characteristics of "resistive" caused by a combination of resistance to the legs, internal connections, plates and electrolyte. Thus form a resistive characteristic ESR, because if it is portrayed as if such be installed in series with the capacitance of Elko.Ideally, an Elko ESR is zero, but in practice this is impossible.Elko High voltage tends to have larger ESR than the low voltage ElkoElko with small values ​​tend to have higher ESR values ​​greater than Elko.Elko 105 degrees (C) tend to have higher ESR than Elko 85 degrees (C).


What Is the ESR-meter?
ESR meter is a kind of ohm-meter that can be used to measure the amount of "resistance" of Elko. Difference if the ohm-meter using a dc current (direct current) to drive the meter, then use the ESR meter ac (alternating current) with a standard frequency 150Khz. As had been explained that ideally Elko its ESR is zero. But this is not possible in practice. Elko good quality 10uF value is close to zero or more generally.


What is the cause of ESR Elko subject to change.
  • The first is caused because of the connection quality is poor constituents. It can be found in Elko Elko New and old.
  • Both are caused due to dry the liquid electrolyte due to evaporate or leak, which can be found at the old Elko. Are the consequences of large ESR Elko turned into?



Consequences of changing the value of ESR Elko
  • Elko is a working principle can be "in-fill and waste of" electric charge repeatedly. Thus ESR Elko-charging current will be passed this exile repeatedly in accordance with the working frequency of the circuit. And we certainly have understood that if bypassed resistor will generate heat flows in accordance with the magnitude of the current strength through resistance value and the corresponding magnitude. Similarly, the Elko with ESR, the greater the greater the ESR value of the heat arising in Elko, and the higher the frequency the greater the heat generated. This heat can eventually cause the electrolyte evaporates into a gas and seeped out, so the value of Elko will turn down. In the specific cases heat can even make Elko explode.
  • On a circuit that works at high frequencies Elko should have zero resistance to the high frequency signal. If the ESR of the resistance turned into Elko is no longer zero, and if the resistance value change is large enough to make the workings of the chaotic circuit.


Our experience with the use of ESR meter in the aircraft repair older model (the old plane), the first one we always do is:
  • Check out all the Elko with ESR-meter at the SMPS, Horizontal and Vertical and immediately replace it if the ESR problem.
  • Check visually (with a magnifying glass if necessary) solder-solder on the SMPS, the output Horizontal, Vertical output, and the CRT socket pcb and soldering again if there appears a problem or suspicious solder it.
  • Both of these were able to eliminate the difficulties that may arise and difficult to trace, so the use of ESR meter can shorten repair time.



How to use homemade ESR meter (calibration)
  • Once the tool is finished
  • Collect some old Elko is still good. Find Elko pcb traces of the plane, made in Japan or Europe the original (former aircraft engine change) because of generally good quality for use as a reference.
  • Grouped on the basis of a value less dar 2.2uF, 4.7uF is less than, less than and greater than 10uF 10uF.
  • Try using the ESR-meter to measure each group, and mark the position of the needle meter on each group
  • These markers can be used as a reference to the appointment of Elko ESR is still good.
  • If the meter needle to deviate less from the reference mark, the mean ESR Elko is not good.


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Monday, August 25, 2014

Sound Level Meter



This is a wonderful schema which gives an attraction for your amp or audio setup so after fixing correctly you will be able to get maximum harvest of it.






Parts List.

Q1 BC 558 PNP Transistor
LED1-LED10 Standard LED or LED Array
R1, R3 1K 1/4W Resistor
R2 10K 1/4W Resistor
R4 100K 1/4W Resistor
R5 1M 1/4W Resistor
D1 1N4001 Silicon Diode
U1 LM3915 Audio Level IC
MISC Board, Wire, Socket For U1
C1 2.2uF 25V Electrolytic Capacitor
C2, C3 0.1uF Ceramic Disc Capacitor
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Tuesday, August 19, 2014

Volt meters ampere meter with PIC

Volt meters & ampere meter with PIC can be used to measure voltage and current simultaneously. The series of volt meters & ampere meter with PIC16F876A PIC is used as a data processor voltage and current are measured. 

This circuit uses the viewer in the form of 16 × 2 LCD used for the data menmpilkan voltage and current measurements. In the article volt meter and ampere meter with PIC are discussed kerannya limited to devices only. More detail can be seen from the image sequence volt meter and ampere meter with PIC below. 

The images of Volt Meter & Ampere Meter With PIC Circuit

Volt meters & ampere meter with PIC 

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