Electronics Forum (Circuits, Projects and Microcontrollers) An electronics forum to talk all about circuits and projects. Thu, 22 Nov 2018 10:25:57 +0000 Thu, 22 Nov 2018 10:25:57 +0000 Electronics Forum (Circuits, Projects and Microcontrollers) http://www.electro-tech-online.com/ Hitachi 50" DLP Rear Projection TV - Help with Blue Dots/Fog Thu, 22 Nov 2018 09:58:09 +0000 http://www.electro-tech-online.com/threads/hitachi-50-dlp-rear-projection-tv-help-with-blue-dots-fog.155467/ http://www.electro-tech-online.com/threads/hitachi-50-dlp-rear-projection-tv-help-with-blue-dots-fog.155467/ invalid@example.com (synergy88) synergy88 Hello, I hope this note finds you well!

I am looking for help with polarizing filter part(s) to fix my Hitachi 50" rear projection TV and your assistance with a source who sells polarizing filters (glass rectangles, I presume) to the public. Any instructional videos would also be helpful as well as tips for a first time DIY repair. I am confident in my repair abilities and just need the part and instructions on the install.

The TV is from 2006 and has served well to date, except for the...

Hitachi 50" DLP Rear Projection TV - Help with Blue Dots/Fog]]> 4 Math Formula to calculate DC power supply capacitor value? Thu, 22 Nov 2018 09:42:05 +0000 http://www.electro-tech-online.com/threads/math-formula-to-calculate-dc-power-supply-capacitor-value.155476/ http://www.electro-tech-online.com/threads/math-formula-to-calculate-dc-power-supply-capacitor-value.155476/ invalid@example.com (gary350) gary350 Is there a math formula to calculate the correct size of a DC power supply capacitor?

Or is it easier to keep making the capacitor larger until AC ripple is gone?

What is best circuit drawing some have capacitors only & some have a choke coil too?

I read bleeder resistor should put 10% load on the power supply? This seems like a lot of wasted power.

I usually use my AC volt meter to check AC ripple on a DC power supply if 20 DC checks 1 volt AC I know it needs more capacitors. I know...

Math Formula to calculate DC power supply capacitor value?]]>
what is ePWM? Thu, 22 Nov 2018 08:52:24 +0000 http://www.electro-tech-online.com/threads/what-is-epwm.155517/ http://www.electro-tech-online.com/threads/what-is-epwm.155517/ invalid@example.com (Shadow_warrior) Shadow_warrior I am using Texas Instrument TMS320F28377S and in that there is Type 0 ePWM module. How it is different than normal PWM modules and what is Type 0 in that?
here is the pdf]]>
Tuning a loopstick to 3rd harmonic Thu, 22 Nov 2018 08:44:57 +0000 http://www.electro-tech-online.com/threads/tuning-a-loopstick-to-3rd-harmonic.155494/ http://www.electro-tech-online.com/threads/tuning-a-loopstick-to-3rd-harmonic.155494/ invalid@example.com (dr pepper) dr pepper I'm revisiting an old project.
I want to pick up 100khz loranc on a loopstick.
I can tune said loopstick to 33 khz 66khz and I sorta get a recognizable loran signal but messed up with local higher power stations, 100khz is completely wiped out by a local transmission.
So before I try some eleborate and therefore non functional filter circuits I was thinking of trying to tune said loopstick to 300khz and see what happens, 300khz is quiet on a comms receiver here.
Any better ideas?]]>
Please help identify a SOT23 diode that goes across the rectified mains? Thu, 22 Nov 2018 08:12:03 +0000 http://www.electro-tech-online.com/threads/please-help-identify-a-sot23-diode-that-goes-across-the-rectified-mains.155515/ http://www.electro-tech-online.com/threads/please-help-identify-a-sot23-diode-that-goes-across-the-rectified-mains.155515/ invalid@example.com (Flyback) Flyback Hi,
We have an offline LED lighting product from an old company. It had been running on the mains for two years.

It has a high voltage linear regulator just downstream of a mains diode bridge (there is no smoothing capacitor after the diode bridge) . The regulator output is 2.5V. It just supplies a microcontroller. Connected from output to input of this regulator, is a SOT23 diode. This diode obviously stands off the rectified mains haversines (339Vpk).

An ex member of staff assures...

Please help identify a SOT23 diode that goes across the rectified mains?]]>
Non polarized radial electrolytic capacitor? Thu, 22 Nov 2018 05:33:24 +0000 http://www.electro-tech-online.com/threads/non-polarized-radial-electrolytic-capacitor.155489/ http://www.electro-tech-online.com/threads/non-polarized-radial-electrolytic-capacitor.155489/ invalid@example.com (Chevboy0167) Chevboy0167 Hello everyone. New to this forum but not electronics. Or so I thought. I mainly work on/repair cb and ham radios. But I do dable in home stereo receiver repair if I think I can. Mainly recaps and power supply rework.

But I have hit a snag. Recapping a 1992 Technics SA GX330 home receiver, and I have found some radial electrolytic caps that look non polarized. Also the board icon shows it looks like a standard ceramic disk cap.

Circuit diagram and parts list show it just like the...

Non polarized radial electrolytic capacitor?]]>
Rotor field and Stator field Thu, 22 Nov 2018 03:52:09 +0000 http://www.electro-tech-online.com/threads/rotor-field-and-stator-field.155516/ http://www.electro-tech-online.com/threads/rotor-field-and-stator-field.155516/ invalid@example.com (blackbeen) blackbeen Hello,
I wanted to understand why the angle between the stator field and the rotor field should be 90 degrees for maximum torque? Just wanted to add it is BLDC motor.
Please advise. Thanks!]]>
Project Thu, 22 Nov 2018 03:18:39 +0000 http://www.electro-tech-online.com/threads/project.155513/ http://www.electro-tech-online.com/threads/project.155513/ invalid@example.com (Happyengineer) Happyengineer A proposed project on an arduino digital fuel level and leak sensor with GSM modem]]> 19 FSK Equations Wed, 21 Nov 2018 23:59:26 +0000 http://www.electro-tech-online.com/threads/fsk-equations.154807/ http://www.electro-tech-online.com/threads/fsk-equations.154807/ invalid@example.com (derick007) derick007 I am trying to derive an equation for an FSK signal in the time domain - see FSKTime

I then want to use Fourier analysis/transforms to find an equation so that I can plot the frequency response - see FSKFreq

I think I am nearly there, but the 2 delta terms and the minus signs in the FSKFreq document are concerning me]]>
Choke Coils Wed, 21 Nov 2018 22:05:23 +0000 http://www.electro-tech-online.com/threads/choke-coils.155512/ http://www.electro-tech-online.com/threads/choke-coils.155512/ invalid@example.com (Lineman) Lineman I am making a woodworking dust control station using a squirrel blower off of an old furnace (1/4 horse). I need to slow down the fan output without raising the amperage. I have learned that I can use a resistor coil (also called a choke coil) to lower the voltage and the amperage. These coils were common on equipment in the 1960's. Can these still be found and if so what size would I use? EV]]> 7 Nissan Transmission Stepper test circuit Wed, 21 Nov 2018 21:03:36 +0000 http://www.electro-tech-online.com/threads/nissan-transmission-stepper-test-circuit.155506/ http://www.electro-tech-online.com/threads/nissan-transmission-stepper-test-circuit.155506/ invalid@example.com (ShawnR) ShawnR Hi All

A friend asked me to test a stepper motor out of his Nissan Murano Transmission. I found a video of someone that did what I wanted to do but the poster has not offered up any info. It looks like an Arduino in the background to me but I have not used one of them.

In my past, I have not yet been successful getting any stepper motor to work with a microcontroller. I stumble around a little with them but I have never had a project for one so never...

Nissan Transmission Stepper test circuit]]>
GPS Satellites Visible But No Fix Wed, 21 Nov 2018 20:55:41 +0000 http://www.electro-tech-online.com/threads/gps-satellites-visible-but-no-fix.155514/ http://www.electro-tech-online.com/threads/gps-satellites-visible-but-no-fix.155514/ invalid@example.com (Nishanthz) Nishanthz Hi,
I am using Quectel L86 GPS Module, I am facing following problems:-
1. GPS Satellite Fix takes more time or sometimes not at all fixing. (Even using external chip Antenna problem exists)
2. Which of these following satellites, I need to enable:- (All I need to enable or according to my location I need to turn ON/OFF)
* GALILEO_Enable
* GLONASS_Enable
* GPS_Enable
3. Even in 12-15 Satellites View also.... The GPS not giving same location repeatedly..It is giving...

GPS Satellites Visible But No Fix]]>
Faulty Spa/Jacuzzi Controller - Possible Capacitor Issue?? Wed, 21 Nov 2018 20:20:23 +0000 http://www.electro-tech-online.com/threads/faulty-spa-jacuzzi-controller-possible-capacitor-issue.155511/ http://www.electro-tech-online.com/threads/faulty-spa-jacuzzi-controller-possible-capacitor-issue.155511/ invalid@example.com (Halsey) Halsey Hi, I am new to this forum and I make no pretence to know my way around small electrons (as opposed to the big ones that drive conveyors and crushers!!!) Hoping someone might be able to provide me some guidance. I bought a second hand spa (2010 Sundance Optima) and installed it two months ago. It ran fine until last week then the controller display started flickering. Usually switching the power off and on again a minute or so later got her running again, however two days ago i got a frozen...

Faulty Spa/Jacuzzi Controller - Possible Capacitor Issue??]]>
Thats a fast reverse gear Wed, 21 Nov 2018 18:01:29 +0000 http://www.electro-tech-online.com/threads/thats-a-fast-reverse-gear.155457/ http://www.electro-tech-online.com/threads/thats-a-fast-reverse-gear.155457/ invalid@example.com (tvtech) tvtech
Creating A New Thread - A Few Tips Wed, 21 Nov 2018 17:12:54 +0000 http://www.electro-tech-online.com/threads/creating-a-new-thread-a-few-tips.108566/ http://www.electro-tech-online.com/threads/creating-a-new-thread-a-few-tips.108566/ invalid@example.com (ElectroMaster) ElectroMaster Please note that in order to create a new thread you must have at least 25 posts and we urge you to read the Rules Thread for this forum.

Creating A New Thread

The following information is required in all threads:

- A description of the product and as much information like model number, brand, etc.
- The terms of the deal such as price, shipping fees, etc.
- Your location (just your...

Creating A New Thread - A Few Tips]]>
Twos compliment in Oshonsoft and Compass calibration Wed, 21 Nov 2018 15:57:54 +0000 http://www.electro-tech-online.com/threads/twos-compliment-in-oshonsoft-and-compass-calibration.153076/ http://www.electro-tech-online.com/threads/twos-compliment-in-oshonsoft-and-compass-calibration.153076/ invalid@example.com (camerart) camerart Hi,
I've asked a similar question in another thread, but this is to clarify a point.

I am getting results of a HIGH BYTE and a LOW BYTE. The D/S points out that these are in 'twos compliment form'

Am I correct that these two BYTEs must be converted to a WORD, then 'twos complimented' or are the two BYTES used 'against' each other in a calculation?

Thanks, Camerart]]>
Need for technical support for IGBT Infineon Wed, 21 Nov 2018 15:50:59 +0000 http://www.electro-tech-online.com/threads/need-for-technical-support-for-igbt-infineon.155510/ http://www.electro-tech-online.com/threads/need-for-technical-support-for-igbt-infineon.155510/ invalid@example.com (nguyenino) nguyenino We are using the IGBT model Infineon FS450R17KE3 with drive ABB model AGDR-71C together. We would like to know that if we replace the IGBT FS450R17KE3 by the new IGBT model FS450R12KE3, is it possible or not?
FS450R17KE3-AGDR-71C (4).jpg]]>
Maxim Analog switch selection Wed, 21 Nov 2018 11:21:26 +0000 http://www.electro-tech-online.com/threads/maxim-analog-switch-selection.155454/ http://www.electro-tech-online.com/threads/maxim-analog-switch-selection.155454/ invalid@example.com (SPDCHK) SPDCHK I have built quite a few solar charge controllers for domestic use on 12V LED lighting.

In my last design I have used the ACS712-05 hall effect breakout board to measure a range of ± 5A fed into the battery from my 150Watt solar panel (via the charge controller)

During daytime when the battery is charging...

Maxim Analog switch selection]]>
Problem in running LTSpice Wed, 21 Nov 2018 02:02:10 +0000 http://www.electro-tech-online.com/threads/problem-in-running-ltspice.155507/ http://www.electro-tech-online.com/threads/problem-in-running-ltspice.155507/ invalid@example.com (Sham J) Sham J I cannot run my diagram...it kept popping out (Could not open library file "DigitalLogic.lib" )
What is the error an how to solve it.
Some components gone missing and I download n save it in lib..I suspect thats the problem
How to solve it?? anyone...]]>
Help to recognize the IC marking Wed, 21 Nov 2018 01:21:45 +0000 http://www.electro-tech-online.com/threads/help-to-recognize-the-ic-marking.155499/ http://www.electro-tech-online.com/threads/help-to-recognize-the-ic-marking.155499/ invalid@example.com (Willen) Willen The IC used in a power supply as a switching IC of KONKA TV mainboard. The marking "out" and other tiny letters seems unique or encoded. There I can see the IC driving a small smd transistor (maybe) and the transistor driving the final MOSFET which is driving the transformer.

So what is the real number/name of the IC (6 pin SMD) so that I can search about it or replace it.]]>