Sunday, 26 July 2015

DIY frequency counter

There is no excuse anymore not to provide your receiver or transmitter with a frequency counter.
For 6 euro's I built a counter which measures frequencies from 1 Hz till 50 MHz.
I ordered the "Do It Yourself" kit here:

http://www.banggood.com/buy/Sku184055.html

The counter can also be used as crystal tester.

The counter is designed around a PIC 16F628 that also contains a table with most used IF frequencies which you can add or substract from the measured frequency.

Very nice design with big LED displays !


Kit parts

Half way


                                 The counter works ! 16 MHz X-tal here under test


Close look with 4 MHz X-tal under test

Wednesday, 15 July 2015

Collector items

Yesterday I found a box with old components. Some of them were germanium transistors.
I must have kept those semiconductors since about 1977. I remember building a simple MG-radio receiver with an AC125. 
I am not good at throwing away things. Now these components have become real collector items.

http://www.ebay.com/itm/OC140-Transistor-Vintage-Philips-Stock-/231620456594?pt=LH_DefaultDomain_3&hash=item35eda7b092