Hi guys i am here again with the project of a high impedance microphone and pickups preamp. You can build it easily. It works with Crystal Microphones and all other high impedance microphones. Also we can use it for pre-amplification of any piezo transducer. Also it works very well with a Guitar magnetic coil pickups.
Here is its circuit i designed it and it is very simple and consist of few components. Components can be found at your local radioshack stores. And really no professional experience is required to build it. You can make it within 15mins. It cost only 1$ due to my area where all the things are very cheap for me. But i believe this won't cost you more than 2$.
So have a look of its circuit:
You can click to enlarge this schematic.
Well i built it in a plastic box that is an electric switch box. Mostly being used in home electrical wiring.
Just drill the holes and put the switches and input and output jack. You can use a battery clip for supplying the power. Also put a metal plate and paste it of any of the side of this box and solder the ground wire of your circuit with it. This would be very good for the high quality gain. I have used a DC noise filter circuit in it that is also very simple. You can use it to filter the clean DC power supplies i'll post that circuit too but not now maybe after next project.
Use a 9v battery which is rechargeable and its recharging circuit is also very simple:
It a simple 9v battery charger circuit and it works 100% fine. Remember that the timing of charging depends upon the number of amperes you are supplying. So Google for it.
You need to make connection to the battery and the pre amp with this circuit in such a way that if the switch of preamp is turned on then the charger do not charge. Yes..!! you need a two way switch. Following diagram make the idea clear:
In such a way you need to make the connection. This will not mess your pre-amp. And so the pre amps completed. It will become a small portable and rechargeable preamp. And you can build it and show it easily. From me its a perfect DIY preamp for piezo and crystal mics. And it is unique because its a chargeable pre amp.
You can also connect DC jack direct to the battery but above method is 100% safe for battery and amp kit.
So here are the pictures of my pre-amp
So have a wonderful project..!!
[Next Projects - Guitar Overdrive Pedal DIY and DC power supply noise filter]