Amateur Radio Stack Exchange
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What does a SSB frequency actually indicate?

An SSB signal is an AM signal with the carrier and other sideband filtered out, if I understand correctly. As such, when specifying an SSB frequency do you specify the carrier frequency, then state which sideband, or do you specify the frequency the…
Adam Davis
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Is there a special name (and if so what is it) for this flush-style SMA variant?

I have some radios that have a special antenna connector. It looks like an SMA connector, but the dielectric is flush with the end of the connector: rather than recessed the way "normal" SMA connectors are: The consequence of this is that the…
user3486184
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Resort FM radio station

I stayed at a resort in the U.S. recently that is located in an unpopulated area with virtually no radio reception. To fill the gap, the resort has its own FM station that can be heard only within the resort (about a minute after you drive off the…
JoelFan
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How is the IF for a superhet selected?

There seem to be almost as many choices for the intermediate frequency (IF) as there are superheterodyne receivers and transceivers out there. The ones I have come across are 455 kHz, 452 kHz, 1.6 MHz and 6 MHz. What would be the rationale for…
VU2NHW
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Why does the FCC put restrictions on symbol rates?

This answer claims that Mostly, on HF, the FCC has chosen to limit modes of transmission and symbol rates rather than bandwidth Why does the FCC limit symbol rates?
Geremia
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What "test transmissions" are allowed above 51MHz?

The ARRL's band plan chart includes the following text in its legend: Test transmissions are authorized above 51 MHz, except for 219-220 MHz What FCC regulation is this referring to? Aren't all ham bands available for transmitter testing and other…
natevw - AF7TB
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Amateur radio in an EOC?

Consider a small town's emergency operations center. While there are amateur radio operators involved, they primarily work for government or public safety, and there is no active ARES participation. The EOC is reasonably well-equipped, with…
Dan KD2EE
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What kind of antenna is that one?

Yesterday I saw the following antenna: I am very puzzled, at first glance it seems a simple dish but: The mesh is really wide (low frequency?). It is pointing to Zenith. I think that most dish antennas rest in zenith position to offer less…
Seitam
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How to do APRS in real wilderness?

I'm a relatively new ham (licensed a couple of years ago, occasional activity on 70cm and 2m, mostly repeaters). I'm looking to extend my ham experience and am interested in digital and packet modes. I'm interested in APRS. The main reason is to…
hamster
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Why does "high SWR" damage transmitters, instead of "impedance mismatch"?

In the audio realm, where cable lengths are insignificant compared to the signal wavelength, I would understand an impedance mismatch damaging an amplifier as follows: Take an audio amplifier that can deliver 100 watts of power into an 8 ohm speaker…
natevw - AF7TB
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What is the origin, history behind "Ben's Best Bent Wire"?

Bens Best Bent Wire My uncle, who was a Merchant Marine in WWII used to tell me this. He was a ham, and said it would develop my fist musically. I was a small child at the time, and through his enthusiasm for all things geeky, especially Ham Radio,…
tallship
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What is the difference between channel & frequency & band in RF?

I am reading about wireless networks basics. I found three terms I cannot find exact definition for: channel, frequency band, frequency. Can anyone give exact definitions for them?
ashok
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How much RF energy do trees and branches absorb?

For the 20m - 10m and 6m bands, will having my dipoles below the tops of trees (I live in redwood forests) drastically affect the RF power out or radiation patterns of my dipoles if I can still get them at least 1/4 wavelength above the ground? Or…
gdc
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What are the relative bandwidths of the amateur bands?

While I was operating on 40 m for Field Day, I noticed a higher SWR than when I first set my antenna tuner for the band. This happened, of course, because I was in a different part of the band, but I hadn’t done enough HF operation to expect the…
Kevin Reid AG6YO
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What is generally considered "too much" power for JT-65 on HF?

Recently, I have begun experimenting with JT-65A, mostly on 20 meters. I usually run about 5 watts with that mode, since I know that JT-65 is a weak-signal mode. Is that still too much power? What is generally considered excessive power on JT-65?
krzysz00 KF5SOQ
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