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1500 questions
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How do businesses develop and test amateur radio products in the US if you cannot be paid for amateur radio use?

Certainly there are companies in the US (like Kenwood) that develop HAM products that transmit. For development and QA they would likely need to test the product outside of a Faraday cage. How can companies test those products in the HAM bands if…
KJ7LNW
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Purpose and sizing of capacitors placed across RF push-pull power amplifier transformer windings

I keep finding RF push-pull power amplifier designs specified with a small(-ish) capacitor across the primary (or secondary) windings of the coupling transformers. Here's an example: This is one example with capacitors across all windings, but I…
Buck8pe
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Transmitting Morse Code as Tone vs. Carrier

Normal CW is just carrier on/off; this means simple transmitters are possible. The BFO of the receiver is adjusted to give a tone in the speaker within the audio passband. Narrow band filtering is done and noise performance is good. I have seen some…
Autistic
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Extra class first?

I want to get my ham license. The first 2 exams are not bad but the 3rd one is really hard. I heard it's best to start with the 3rd license because one can get a good call sign. Is this true and is it worth it?
Ownt
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So how do HF nets work, anyways?

I'm familiar with VHF/UHF repeater-based nets and the general concept of how nets work (net controller that you check in with, net controller says who talks, people send it back to the controller after talking, and so on). But how do HF nets work?…
QuantumMechanic
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How much attenuation (dB) from a balun is expected?

I'm building a dipole antenna for 433 MHz, first one ever. I will have to use a ferrite bead to balance the feed. How many decibels of attenuation should I expect from the ferrite bead?
AllYourBaseAreBelongToUs
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FT8 etiquette when no reply after responding to CQ?

When you respond to an FT8 CQ and the other side doesn't respond after a couple of your transmissions, what is proper etiquette? (Assuming you're working split and not transmitting on his receive frequency.) Should you keep transmitting so he knows…
QuantumMechanic
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Simple AM receiver with gnuradio / RTL-SDR

EDIT: I have succeeded in getting the AM receiver to work, by replacing the AM Demod block with a Complex To Mag, and a Band Pass filter (this is noted as an alternative in the AM Demod docs). Consequently, while I've proved that most of what I did…
Toby Eggitt
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Replacing hand-wound inductors with store-bought versions

I'm wading through some schematics for a direct conversion I-Q SDR receiver, and there is an L-C band-pass filter on the input. Each inductor is specified by an inductance, a toroidal core material, a wire gauge (AWG), and a number of turns. I…
W5VO
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When is a balun a Guanella?

I've searched this site, wikipedia, other sites, and haven't found a clear answer: What features or parameters of a balun or choke put it into the category/definition of a "Guanella"? Where does the name come from?
Jay Rabe - KJ7TTT
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Why does a sine wave show two peaks in the frequency domain on GNUradio?

I constructed the flow graph in GNUradio 3.7 as below: I know a sine wave has only one frequency, so what causes the frequency sink to show two peaks?
kittygirl
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Operating on foreign US soil

Some places, like embassies and military bases, are considered US soil, even if not traditional. Can one operate with a US call sign in such situations, and how should it be done?
PearsonArtPhoto
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Using standard headphones with the Yaesu FT-60?

I just got a Yaesu FT-60R handheld, along with the MH-37A4B earpiece. After having it around for a couple days, I think I'd like to be able to connect standard headphones to it, so as to be able to listen privately without carrying around an extra…
Kevin Reid AG6YO
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Does the waveform of the VFO necessarily have to be sinusoidal?

Looking around for a VFO online, I see most kits/manufacturers make it a point to mention the waveform. Sinusoidal is a fundamental shape, whereas others (sawtooth, square) are a composite. I recall reading online (can't remember where it was) that…
VU2NHW
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Where can one get a "listed" SO-239 lightning arrester?

According to this summary of NEC requirements for radio antenna grounding (from 2014, but hopefully still somewhat accurate): https://www.mikeholt.com/files/PDF/Radio_and_Television_2014NEC.pdf It says "Antenna lead-in surge protectors must be…
User5754448
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