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Home > Mobile Electronics > Radar Detectors > K40 RD850

K40 Portable All-Band Radar And Laser Detector - RD850 - RD850

Abt Model: RD850

Discontinued Product This item is no longer available from our website.

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K40 Portable All-Band Radar And Laser Detector - RD850

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K40 Portable All-Band Radar And Laser Detector - RD850/ Detects X, K And Superwide Ka Band Radar And Laser/ Patented Intermediate Frequency Rejection Software/ Unique "5-Window" Design/ VG-2 And Pulse Protection/ Signal Alert And Band Indicator/ Ticket-Free Guarantee

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Product Details

K40 Portable All-Band Radar And Laser Detector, Model RD850

The only portable all-band radar and laser detector with a ticket-free guarantee. This is total speeding ticket protection! The only portable detector you'll ever need. And only from K40 Electronics. Designed from the same technology as our signature Undetectable Remote Systems, the RD850 is a technological marvel in a sleek package that requires no installation. Just mount it on your dash, visor, or windshield, and plug it into your cigarette lighter (can also be connected to your fuse box). Dismounts in seconds too. So it's perfect for second cars or rental cars.

Features:

Detects X,K and Superwide Ka band Radar and Laser
Advanced Microwave Radar Receiver Design
For exceptional performance to all radar guns, including DSP driven Ka band radar.
Patented Intermediate
Frequency Rejection Software
Reduces non police signals without sacrificing performance to true police radar.
Unique "5-window" design
Helps this detector pick up laser signals front and rear, even off axis signals.
VG-2 Protection
Prevents detection from the VG-2 Gun (radar detector detector) while emitting a brief audible and visual alert.
Pulse Protection
Immediately alerts you to police "Instant on" radar.
Signal Alert Indicator
Four LED's illuminate as the strength of the police radar signal increases.
Band Indicator
Audio and visual alerts combine to alert you to radar or laser signals.

K40 RD850 Guarantee:

Total Immunity From Speeding Tickets
We'll pay any or all radar or laser speeding tickets you get for one year after purchase.
Total Guarantee Of Performance
If your new RD850 does not outperform any other Radar/Laser detector you've owned, return it within 7 days for full product credit.
Total Guarantee Of Quality Workmanship
We'll pay for any and all repairs or replacement of defective parts for 12 months after purchase.

Approximate Weight:

Shipping: 5 lbs

Product Review Summary

4.5 (based on 10 reviews)

90% of respondents would recommend this to a friend.

Pros

Good Sensitivity (9)
Clear Alert (8)
Easy To Mount (8)
Versatile (6)
Durable (5)
Neat Features or Extras (3)

Cons

Best Uses

Highway Driving (9)
City Driving (6)
Rural Driving (4)

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Showing 1-10 of 10 Reviews

5.0

This detector is GOOD [*]

Reviewed by AskHack (Owned 9 detectors) from Chicago, IL on Jan 06, 2010

BOTTOM LINE Yes, I would recommend this to a friend.

[*] This radar detector even though old and hard to get now has BETTER K band than the newest passport 9500i. The ka band reception is really good as well, but I don't have a permanent source to test that. It's competition of the era was the passport 8500 and was proven to exceed it's performance. Just today it picked up laser scatter a MILE from a laser trap that had 9 state troopers. I have only had one other detector detect scatter (passport 9500i) and it was nowhere near as thick as the traffic was today, and at nowhere near the range.

Best Uses:	City Driving, Highway Driving
Cons:	Does not talk
Pros:	Good Sensitivity, Low False Alerts

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1.0

K40 RD850 SUCKS!

Reviewed by speed racer (Commuter, Tuner) from Boston, MA on Dec 06, 2008

BOTTOM LINE No, I would not recommend this to a friend.

Bought this for my trips from MA to MD and my commute to work. Does not detect the troopers @ all! Only thing that will go off is those construction electric road signs and those portable radar checkers that shows your speed.

Pros:	Easy To Mount
Cons:	Gives False Reads, Inaccurate

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4.0

Jury still out on this one.

Reviewed by Dave (Practical, Commuter) from Danville, CA on Nov 30, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

I am still learning how to recognize real alerts from false alarms, they are difficult to distinguish, but this is my first detector, and this may be normal.

Cons:	Gives False Reads, Goes off alot w/o reason
Best Uses:	Highway Driving, City Driving, Rural Driving
Pros:	Neat Features or Extras, Good Sensitivity, Versatile, Clear Alert, Durable, Easy To Mount

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5.0

VERY VERY GOOD RADAR DETECTION

Reviewed by DMANDRUMMER (Commuter, Gearhead, Practical) from WYOMING on Nov 12, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

I HAVE HAD MANY REDAR DETECTORS IN THE PAST BUT THIS ONE HAS SAVED ME TIME AND TIME AGAIN. IT IS BY FAR THE BEST I HAVE PURCHASED. i HAVE HAD MINE SINCE 2001 AND IT STILL DOES NOT SKIP A BEAT. GOOD JOB K40!

Pros:	Good Sensitivity, Easy To Mount, Clear Alert, Durable, Versatile
Best Uses:	Highway Driving

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5.0

My 2nd K40

Reviewed by Duane (Practical, Commuter) from Dallas, Tx on Nov 07, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

2nd model has fewer false alerts It works great, neither model has ever failed me!!

Best Uses:	City Driving, Highway Driving
Pros:	Easy To Mount, Good Sensitivity, Clear Alert, Versatile

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5.0

One great radar detector

Reviewed by mrcool (Practical) from enid, oklahoma on Oct 29, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

Love the radar detector. This is my second one. Wife wanted one that didn't cause the cell phone to mess up. This one fits the bill.

Best Uses:	City Driving, Highway Driving
Pros:	Good Sensitivity, Best detection, Easy To Mount, Clear Alert

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4.0

Best of three I have owned

Reviewed by The dog guy (Practical, Commuter) from Idaho Falls, Idaho on Sep 20, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

I wish the signals were easier to read so I knew what radar was being used. Alert is excellent.

Cons:	Exact type of signal
Best Uses:	Highway Driving, City Driving
Pros:	Versatile, Durable, Easy To Mount, Good Sensitivity, Neat Features or Extras, Clear Alert

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4.0

So far so good

Reviewed by Cal the Commuter (Commuter) from Milwaukee, WI on Sep 04, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

I commute 140 miles a day and have found the K40 to be a reliable source to detect police radar. So far I have been "warned" of police radar roughly 1/4 mile before seeing the squad.

Pros:	Clear Alert, Durable, Good Sensitivity
Best Uses:	Rural Driving, Highway Driving

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5.0

Best detector on the market!

Reviewed by online shopper (Tuner, Gearhead, Practical, Commuter) from Brimingham, AL on Aug 07, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

I have owned an Escort X50 and a Beltronics and the Valentine 1. All 3 were more expensive and had more false warnings. I purchased the K40 RD850 after tons of online research. It's old school display grows on you with it only being Led's. The volume is plenty loud even if you run your radio at its highest volume like me. [...] I have used the unit for almost a month and it's surpassed all my high expectations as far as performance. I like the fact it came with all the needed accessories for mounting. I do not like the suction cups in the middle of the windshield and the wide spiral cord hanging down the windshield. It screams to cops and thieves "hey look....I have a nice radar detector. I used the visor mount and straight power cord to mount the unit. I tucked the straight cord into the installation around the window and ran the wire myself under the steering wheel to the cig outlet. Piece of cake for even me. The unit is now at eye level and still hidden from thieves or cops. I love it. [...]

Pros:	Best unit for the money, Versatile, No visible wires, Clear Alert, Visor mount, Unit is small, Unit is lightweight, Durable, Good Sensitivity, Easy To Mount
Best Uses:	Rural Driving, Small Cars, City Driving, Mount it on the visor, Larger Cars, Highway Driving

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5.0

Excellent Purchase

Reviewed by Cop Target (Practical, Commuter, Gearhead) from Indian Harbour Beach, FL on Jun 13, 2007

BOTTOM LINE Yes, I would recommend this to a friend.

Great Price [...] I recently bought a new Mustang GT and feel like a cop target, It's nice to know where they are before they see me! If this detector saves you one ticket, it just paid for itself. [...]