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Thinking Out of the Circuit Board

 A Time Long Ago, Things Were Different.





As a homebrewer (starting back in the early 1950's with a CK722 transistor) I find that today we have lost an important insight into what we do. I didn't; but many have.




Gone is the quest to learn new things and to strike out on our own. Frequent emails to me ask where is the circuit board or send me the Gerber Files. That gives rise to several questions.

  1. So why do you need a circuit board and 
  2. Why can't you design one yourself?
The same applies to Arduino Sketches and Code. Typically, most rigs are not totally dependent on just one set of software to run the radio. The problem maybe is that to write code, one would really have to know something beyond asking for the circuit board.

I really don't have any special radio skills. But what I do have is some processes to attack problems and processes to approach a new radio project.  I call it noodling and there is a lot of research that I do up front. The last thing I do is to turn on the soldering iron. Thank God for simulation programs like LT Spice.

That simple one transistor microphone amplifier (above) was extensively simulated and that effort has borne fruit by the number of excellent audio reports. I didn't start with a circuit board. I started by looking at a basic amplifier circuit and on from there. One soon learns how the value of the emitter bypass cap impacts the circuit performance. Now that exercise is a part of my knowledge base.


There are those who will fester over why the resistors R6 - R8? They are there to simulate a 10K output pot. So, when you build the circuit, you install a 10K pot and no resistors.  The output taken from the center wiper to the 0.22Uf cap which connects to the relay terminal. 


But as I share the circuit -- the question persists where do I get the circuit board frequently arises? Lew McCoy, Wes Hayward, Jean Sheppard and James Lamb would not even think of circuit boards! Excelsior!

This is what happens when your mind is on circuit boards and not the circuit... you Strike Out!


That has to HURT!

73's
Pete N6QW


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