Category Archives: Colpitts

Playing with amplifying and tidying up

I sort of reverted back to playing with the amplifier circuit I’d built last month, the little common emitter one with about 10mA collector current on it and about 10 dB gain.  I built it ugly style on a chunk … Continue reading

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Colpitts confusion. Phone a friend?

I read through the analysis presented by Wes Hayward in his Radio Frequency Design book, Chapter 7.  In it he presents the above circuit used for analysis of the Colpitts.  He then proceeds to calculate an input admittance formula as … Continue reading

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Breadboard be gone! And thrill of oscillation and radio.

I discovered (or really re-discovered) that the good old fashioned breadboard, with the little sockets that grasp onto pins and leads, was REALLY messing up my oscillators. I know this comes of no surprise to experienced homebrewers of RF stuff.  … Continue reading

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Oscillating away in Colpitts country

According to Wikipedia, the Colpitts oscillator was developed by Edwin Colpitts in 1918.  I played around with this oscillator when I first started homebrewing around 2002 or so, and never could get it to oscillate for some reason!  Today, much … Continue reading

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