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Tried to add two attachments at a time --- Didn't work...8^( -- Chuck, W5USJ (ex K2OFN) Point, Rains Co, TX? EM22cv

Jerry, I get about 3 kHz with a pair of crystals on 7MHz using the "fixture" in the picture.? I measured that with a 10V tuning range. The SA612?oscillator is running from the 6V regulator circuit

Rob, I would say a couple terms into a calculus sequence for that equation to lose its mystery. So by the end of a freshman year for an engineering student. There is some physics there too, a math

I am a 60 year old retired computer programmer......... with failing vision. I have written software for everything from tiny microcontrollers to track satellites with DOS computers to IBM mainframes

Rob, Ouch! That's going to leave a mark! It's a fair cop, as the Brit villains say. I went through college begging for a grade in calculus, retired two years ago and *finally* started to do some of

And while I'm at it, I'll recommend two other books: The Art of Electronics, Horowitz and Hill. A classic RF Circuit Design, Chris Boswick. Lots of practical design info and exercises Eric KE6US

About 15 years ago, I had a website appropriately called KE6US.com. I actually reviewed both EMRFD and Intro to RF Design. Wes was kind enough to send me a thank you email for the reviews.

It's one thing to build a known good design. Quite another to design something that is fundamentally novel, making the necessary calculations and measurements to get it performing well. Yes, you can

This reminds me of the question I asked in the old group regarding an oscilloscope. I wondered if it was possible to homebrew a sideband transmitter without one, and the answer was "definitely!" It

You will find that there are online calculators or models you can use for most everything you might want to do. The tougher issue is to understand the how and why of electronics. On your own, that

Chuck, that looks pretty good. How much tuning range do you get? Is it best to have the crystals of slightly different frequency, and by how much? How sensitive is the tuning to changes in battery

It all depends on how deep you want to go. For example, most radio amateurs would evaluate an antenna system by measuring the SWR. But you won't really understand it unless you embrace the notion of a

Rob, Start with college-level algebra. My professor called algebra "the language of mathematics". Then, Calculus (1, 2 and 3) along with engineering level Physics (physics with calculus). Then

I agree with Diz on empirical design.? Although I find that collage?algebra** 101?can be most?useful.? Also some high school trig and calculus.? That so when you are reading a paper about

OK...I'll start a fire here... I believe that empirical RF designs will outperform mathematically designed RF hardware every time. Let the flame war begin :) Seriously, I personally do not go beyond

What level of math course would I need to study to learn how to comprehend the equations presented in design books like Introduction to Radio Frequency Design?? by? W7ZOI. I have been tinkering

JT, Kinda late with this.? Attached a schematic and picture?of a simple RX that I've built?like you mentioned.? They are based on versions of the original MRX-40 in 1997 QST, the original Sudden

The Rugster from AA7EE we've been discussing here uses the HiPerMite audio filter, which is a very good CW filter but I think a beginner's receiver should just let them hear the whole audio

Jerry, Just a coincidence but I've also been searching for an interesting project for young builders to tinker with radio circuits.? AA7EE's receiver sketch might serve the purpose.? Would there be

Using the 40A for WES today, set at 1W output and it is still a lot of fun. So far QSOs to IN and OH. Did anyone ever successfully extend the tuning range of this project to take in more of the