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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

Just FYI: From the assembly manual, p.2:? "A user wanting a volume control may substitute a 100k audio potentiometer for R11 and R12." Jerry AA6KI

Thanks Jerry, that helps quite a bit. I may change out t a different BPF design as I have no strong signals of any kind near me. I live out in the middle of the woods and don't have any neighbors.

Correction: freq = 1/(2*pi*sqrt(L*C)) So doubling both L and C with cut the frequency in half. Not to a quarter of the original frequency.

The HiPerMite has no volume control: http://www.4sqrp.com/hipermite.php And this radio has no AGC. So AA7EE's 1k pot is also your only volume control. Jerry

That AA7EE front end is fairly straightforward. The 1k pot is for RF gain in case you are dealing with very strong in-band signal, the SA612 doesn't have a whole lot of dynamic range. The tuned