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0 pointsnovok4y ago0 comments

Maybe they are not regulating radio receiver usage, but the just the possession of it, which would be a separate kind of regulatory space.

0 comments

blantonl4y ago

All radio receivers have local oscillators built into their receiving circuitry that actually transmits energy that can be detected by specialized receivers.

xxpor4y ago

Not only are there radar detector detectors, but then there are radar detector detector detectors, and radar detector detector detector detectors. A hilarious arms race.

ianhawes4y ago

You should be fine with a trace buster.

worik4y ago

> All radio receivers have local oscillators built into their receiving circuitry that actually transmits energy that can be detected by specialized receivers.

All efficient radio receivers....

It is possible to build radio receivers without such. I built a crystal set as a child that could power an air piece without a battery using only the AM signal.

someguydave4y ago

Not so much with modern ADC based receivers, it is possible that the only oscillator is at a fixed frequency and the only “tuning” happens in a computer.

hammock4y ago

That is accurate. Your vehicle is not allowed to be equipped with a radar detector that is powered or accessible to the driver.

The police even have radar detector detectors.

cjrp4y ago

I can’t be the only one thinking “so how do you build a radar detector detector detector?”

VistaBrokeMyPC4y ago

It's basically just a more sensitive radar detector. Instead of picking up the main frequencies radar guns use, it picks up the harmonics emitted by the oscillating crystal inside the radar detectors. All radar detectors leak on harmonic frequencies of the frequency they pick up on, it's just a matter of how much. Those cheap Walmart radar detectors leak so badly they detect each other. Pricier ones are more sophisticated in how they shield.

function_seven4y ago

Could one build an SDR version of a radar detector that doesn't have a detectable oscillator? (Or, if it does, it's oscillating at a much higher frequency?)

I'm no RF guy, so I'm clueless on this stuff. But my understanding is that SDRs aren't radio receivers in the traditional sense. That's the whole "SD" part of it, the device scoops up everything and FFTs it or something.

2 more replies

randombits04y ago

You could tune an antenna to trip a detector detector (side note: which would be some great civil disobedience!), but I don’t think you can get to the detector detector detector without an interaction with law enforcement. Layer eight problem.

CodeAndCuffs4y ago

Some Troopers have a Radar-detector detector (such as the VG-2).

There are Radar Detectors that have VG-2 (Radar detector detector) detectors on them.

I haven't heard of a radar detector detector detector detector. Such a thing would be pretty useless for a cop's intent and purposes.

Wistar4y ago

How do radar detector detectors work? A video.

https://m.youtube.com/watch?v=upCm4ONlvBY

throwaway0a5e4y ago

Which is stupid if the goal is safety. A radar detector makes the user slow down for a much longer area than the sight of a cop car does.

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