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Re: What level math is in the RF design books?
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
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Michael Maiorana
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#364
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Re: What level math is in the RF design books?
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
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Chuck Carpenter
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#363
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Re: What level math is in the RF design books?
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
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w8diz
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#362
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What level math is in the RF design books?
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
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Rob <roomberg@...>
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#361
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Re: 7 MHz Oscillator Ideas
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
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Chuck Carpenter
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#360
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Re: Plug and Play Receiver
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
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Jerry Gaffke
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#359
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Plug and Play Receiver
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
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[email protected]
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#358
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Re: Norcal 40a (Was Re: [qrptech] Group Introduction: If you're going to post on the group, reply here!)
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
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Curt
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#357
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Re: 7 MHz Oscillator Ideas
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
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bleepingbeep
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#356
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Re: 7 MHz Oscillator Ideas
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.
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JT Croteau <jt.tobit@...>
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#355
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Re: 7 MHz Oscillator Ideas
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.
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Jerry Gaffke
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#354
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Re: 7 MHz Oscillator Ideas
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
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Jerry Gaffke
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#353
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Re: 7 MHz Oscillator Ideas
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
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Jerry Gaffke
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#352
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Re: 7 MHz Oscillator Ideas
I've been thinking of taking AA7EE's approach at using NM0S's HiPerMite as the audio chain. I don't fully understand his use of a tuned BPF, my lack of experience is showing here. AA7EE Rugster:
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JT Croteau <jt.tobit@...>
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#351
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Re: 7 MHz Oscillator Ideas
I used a 7.16 mHz ceramic resonator with great success. http://www.learnmorsecode.com/DC/index.html I had those resonators left over from the VK3YE regen projects.
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Rob <roomberg@...>
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#350
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Re: 7 MHz Oscillator Ideas - good enough
JT, This is exactly how I used my old Ramsey kit back in the early '90s.? Had it next to my bed. It was the same NE602/LM386 design. An LC osc using the NE602 internal should work fine. A varicap
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wb6ogd
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#349
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Re: 7 MHz Oscillator Ideas
I like the receiver section of the SST xcvr for an application like this. It even has a simple AGC that works pretty well. You will probably need another stage of audio amplification if you want to
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W0PWE
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#348
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Re: K1SWL has done it again, the Phaser!
Dave has posted on the CWTD Group his thoughts on using a DC Receiver with the Phaser Transceiver: "We considered interoperability between Phaser users to be an important design goal.?? That drove
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Pete WB9FLW
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#347
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Re: 7 MHz Oscillator Ideas - good enough
Hi Bill, CW only. I just want something to monitor 7030 and 7040 while I am smoking a pipe and reading in my single room cabin or drifting off to sleep. 73
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JT Croteau <jt.tobit@...>
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#346
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Re: 7 MHz Oscillator Ideas - good enough
Hi JT, What modes do you have in mind? CW and most of the digital modes are not particularly fussy about a little drift. A free running, L-C VFO should give you what you *need*. The ones I have that
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Bill Cromwell
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#345
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