Instant On detection question

[aradarnut]

Well now getting back to my point.

If its in standby mode this is good. Surely there is some type of harmonic or oscillation going on inside the unit. If so these frequencies ought to be detected by our RD. Im not talking about X, K, or KA band.

Why not have a Radar Detector that detects a radar gun in standby mode by picking up these oscillated frequencies? Kinda like a RDD picking up our RD but just the opposite!!

Of course the radar guns will need the STi stealth detection feature but for now why not take advantage of this possible idea to help protect against IO radar? Maybe the same idea could also go towards laser guns before they are turn on.

Any thoughts on this?

I certainly am no expert on this, but I don't think units in "standby" mode emit enough RF energy from the counting portions of the unit to be detectable within a useful range. Maybe a few feet at the most.

[bart99gt]

Unlike a super-heterodyne type receiver, a radar gun just mixes the return signal with the fundamental, ie., the transmitted X, K, Ka band signal. There's no LO so to speak, like you would find in a radar detector or radio receiver. When its off, there are zero emissions from the radar.

Whatever little EMI is generated by all of the components inside the counting unit is certainly not enough to be detected by something in another vehicle.

[kpatz]

The "release" button would have to do with the "Lock" feature. On all of the units I own, the IO buttons are labeled as: HOLD or STBY (standby), depending on the model. Pressing the lock/release button only locks a speed on the display while the transmitter keeps on going, until HOLD or STBY are pressed again.

My MPH K-55 has a switch labeled STBY/RUN, and the remote has a 3-way switch labeled STBY, FRONT, and REAR. Either switch in STBY causes the unit to not transmit. It also has a LOCK/REL button, which locks the speed on the display.

My Stalker ATR has a button labeled XMIT/HOLD which turns the transmitter on and off, and a LOCK/REL button to lock the speed display. When used in handheld mode with the trigger grip, the trigger turns the transmit on/off, or if switched to constant-on mode via the XMIT/HOLD button, the trigger toggles the display lock/release.

If its in standby mode this is good. Surely there is some type of harmonic or oscillation going on inside the unit. If so these frequencies ought to be detected by our RD. Im not talking about X, K, or KA band.

The radar gun transmits NO microwave frequencies when on standby. The Gunn diode in the transmitter gets no power during standby. About the only emission would be much lower frequencies from the control unit/microprocessor, and just about any device with a microprocessor inside would emit such frequencies, so it can't reliably be used to identify a radar gun from, say, a cell phone, or your car's ECU, your kid's Game Boy or even your car radio. Unlike RDs, radar guns don't have a local oscillator (I don't think), other than the radar transmitter itself. In fact, a basic radar unit such as the MPH K-55 is a very simple device, less complex than an RD in fact.

[aradarnut]

The "release" button would have to do with the "Lock" feature. On all of the units I own, the IO buttons are labeled as: HOLD or STBY (standby), depending on the model. Pressing the lock/release button only locks a speed on the display while the transmitter keeps on going, until HOLD or STBY are pressed again.

My MPH K-55 has a switch labeled STBY/RUN, and the remote has a 3-way switch labeled STBY, FRONT, and REAR. Either switch in STBY causes the unit to not transmit. It also has a LOCK/REL button, which locks the speed on the display.

Yes, switches too. :wink:

[Buford T. Justice]

I sure like to place a radar gun in standby and have a spectrum analyzer take a lookie.

[KustomEagle]

I sure like to place a radar gun in standby and have a spectrum analyzer take a lookie.

You wont find anything interesting. When no power is getting to the gunn oscillator there is nothing coming out period, at least nothing more than what any electrical device would generate. Radar guns are very simple devices when you look at them; there is a gunn oscilator; a gunnplexer mixer some wavegides and a frequency counter that may or may not have DSP to determine same lane direction moving etc that shows the targets speed which is derived from the doppler shift frequency.

The only thing you MIGHT pickup is the quartz oscillator inside that gives the DSP or counting unit its reference signal. And that quartz is a different frequency for ever gun and probably different revisions of the same gun.

if you could pick that up you'd pick up EVERY other device inside the cop car that uses an oscillator which is well, EVERYTHING.

I understand what you want to do but it's really not possible without some sort of active scanner that scans for microwave waveguides gunnplexer/mixer gunn oscillators etc etc.

[KnightHawk]

Of course the radar guns will need the STi stealth detection feature but for now why not take advantage of this possible idea to help protect against IO radar? Maybe the same idea could also go towards laser guns before they are turn on.

Any thoughts on this?

There's nothing to detect when in standby/hold mode.