Hi Friends, 

2 years before, we have launched Forums in CircuitsToday with great expectations. However due to lack of time on our side, we failed to monitor the forums properly. Above all the software we bought to power forums was too susceptible to spam activities. We had a tough time dealing with “automated spam” activities in forums. In 2 years time, the forum was dominated by spammers than real users. This was an unexpected and hard situation. Though we still have good intentions to keep the forum alive, we are forced to take it down for technical reasons and quality control.


What’s on the cards?

We are on way to launch a new Q&A platform on CircuitsToday with a modern user interface. The software development is going on and we will be back with new QA section in the coming months. This QA platform will be having a neat, modern user interface. We also expect it to be well built, so that spammers wont disturb our discussions.



  1. Bob Wettermann

    Zener diode allows current to flow in the forward direction as normal, but will also allow it to run in the reverse direction when the potential difference is above a certain value – the breakdown voltage known as the Zener voltage. The Zener diode specially made to cause a reverse voltage breakdown at a specific voltage. To get more information including for pcb and solder paste stencil you can visit soldertools.net

  2. Ian Skeldon


    I have need of a circuit for a specific function. Several drawings have convinced me that I am almost there but my lack of actual electronics knowledge is holding me back.

    I need a circuit that will allow a dc power supply of between 4v to 16v (will be set to a more specific V at time of use) to power a load of about 3amp max. But the circuit needs to have a second power supply similar to the first which will automatically switch in and stay in when V on the primary power supply drops to a (adjustable) voltage, an indicator such as a LED needs to show that this has happened.

    Can it be done? I have been thinking of Zener diode with a darlington pair driving a power mosfet, capacitor across output so that switchover is not seen by the load.

    Many thanks,