[1284] Rewah Pro from Mission Engineering

Date: July 27th, 2012 | Comments : none | Categories: DIY.

This is the new wah pedal that I have on my board, demoed here by JR Taylor:

 

[1277] LM4562 Precautions

Date: July 24th, 2012 | Comments : [1] | Categories: DIY.

LM4652 dual opamp

The LM4562 is an excellent dual opamp with very low noise and distortion. Its performance is tough to beat for audio use.

However, it appears that the chip is easily damaged. I have blown up 2 of them in the past few months, and prior to that, it has been more than 25 years since I last trashed a bipolar or jfet opamp. Also, I have had reports from a few project builders using my pc boards that have tried the LM4562 and also ended up with fried opamps.

You must not apply reverse power voltage or it is toast. Don’t short the output. Also, handle with care, as you would a mosfet chip. Observe these few precautions and you should have good luck with the chip. I use one in my DIY function generator with excellent results, and another for its low noise/distortion in a brickwall filter.

If you are using the LM4562, and your project is not working, sub in a TL072 or 4558 temporarily and see if that fixes it. If so, you might be better off using a 5532 or a fresh LM4562 that has been carefully handled.

 

[1275] More Patents

Date: July 21st, 2012 | Comments : none | Categories: DIY.

I have added a couple of recent patents to the effects patent page:

http://www.muzique.com/misc/patents.htm