Viewing profile — Johnythree
Johnythree
HN member- Joined
- Sat, Aug 02, 2014, 3:18 AM UTC
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About Johnythree
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Recent public activity
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Comment #43373067
I'm puzzled by this claim. I wouldn't call it a myth, but all the same... I grew up on a vineyard. Each harvest time the grapes would hang down heavily and almost touch the ground.…
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Comment #41961546
AM is a type of modulation which is widely used by many different services (eg Shortwave broadcasting, CB radio, Aircraft VHF, etc). However "Longwave and Mediumwave Broadcast" una…
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Comment #41961488
Transmitters need only be re-certified if they are to be sold in quantity. Once-off Broadcast Transmitters need only demonstrate that they meet the relevant standards. Many of the …
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Comment #41837551
It doesn't. In both it depends on what the stations engineer chooses to transmit.
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Comment #41837522
Most cheap FM receivers definitely use a PLL to detect FM. Giving automatic tuning is just a side benifit.
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Comment #41837501
Most FM receivers can lock on the carrier because they have a "Phase locked loop" to cancel any tuning errors. Many good AM receivers do exactly the same thing, especially those re…
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Comment #41837448
Is commonly known as "Bass Boost". As the OP has said, it cannot give louder bass, but simulates the bass harmonics.
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Comment #41837419
This is yet another myth: The "Woolyness" of AM broadcast (at least in America) is due to the stations purposefully tailoring their audio processing to suit typical cheap AM receiv…
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Comment #41837353
Only while signals are strong. On weak signals however, AM has a considerable benefit in intelligibility over FM.
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Comment #41837347
This is a myth. There is no reason that channel spacing need limit the modulation bandwidth. The only downside is that listeners to adjacent stations will hear a slight "monkey cha…
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Comment #41837298
Yes, this is one of the proposed methods. It's known as "Independent Sideband". It works, but it is a fairly expensive method to implement.
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Comment #41837277
There were a number of successful AM stereo broadcasting methods proposed and trialed. These were completely compatible with conventional AM transmissions. The conceptually simples…
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Comment #41837130
There is no reason that the channel spacing need limit the sideband bandwidth. The only downside to this is that listeners on adjacent stations hear a slight "monkey chatter" from …
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Comment #41478200
The pickle will shunt (steal) some signal, but the radiated power from the antenna will be very much greater than that flowing through the pickle.
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Comment #41478191
Because your nerves don't respond to high frequencies, you cannot "feel" RF current. What you do feel is the intense burning associated with the RF energy being converted to heat.
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Comment #41478149
You have it backwards: Fessenden is famous for developing a electomechanical RF generator which put out a clean sinewave (eg a coherent wave), which helped replace the earlier Spar…
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Comment #40509453
Or even simpler, use a Neon bulb. or even a Fluro light.
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Comment #40437507
The alternative is to do the standard sitting exercises intended to avoid DVT. eg wiggle your toes, flex your leg muscles, rock your feet, etc. All you need do is avoid pinch point…
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Comment #40437416
There are simple exercises that you can do while seated to avoid DVT. Just wriggling your toes help a lot, or flexing the muscles in your legs. I fly a lot on routes over the tropi…
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Comment #40366168
Likewise "Pavane", an alternative history science fiction novel by British writer Keith Roberts.
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Comment #38935599
Any Antenna designer wants to see the antenna being an elevated ground-plane or dipole mounted clear of obstructions well above the phone. However he is stuck with a compromise des…
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Comment #38935383
> antenna is tuned to the maximum allowed emission power per local regulations Actually it's not. The antenna is tuned to give a peak in output. It's either correctly tuned, or it'…
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Comment #38935276
Different body positions are going to affect the antenna tuning differently. And of course different surroundings will also effect the directivity (eg the radiaton pattern). So som…
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Comment #38922935
A more likely theory is that the fob transmitter (and antenna) is tuned to put out max signal when near the body. This is it's normal use. If however you tested it with the fob som…