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Originally Posted by phunk
Anyone know what it means when the V1 is giving a brief radar warning then instantly makes a different beep sound and the display reads and flashes the letter "J"?
I get that maybe once a day, never figured out what it means.
i love this thing. saved my ass countless times.
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http://www.6speedonline.com/forums/s...threadid=21599
This is what Mike Valentine (W8MM) said about the "J" function on the Valentine One.
"A New Warning
V1 has a new feature. When the signal identification system determines that a current warning is not, in fact, a radar threat, it notifies you with a "dee-dah-doo" sound and terminates the warning. At the same time, the letter "J" will flash briefly in the Bogey Counter."
"J" stands for "J"unk signal.
OK, why did we add this new feature? Because it was the best way to give beyond-line-of-sight warning capability for POP-radar signals while not burdening the user with an excess of unresolved alerts (false alarms).
POP signals are short bursts of radar that last only some tens of milliseconds. They are made short in an effort to escape the notice of radar detectors. Simply speeding up the search process of a detector allows high probability-of-intercept for the POP transmissions but introduces another nasty problem -- microwave interference generated by radar detectors in other vehicles causing false alarms.
There are many hundreds of thousands of certain model BEL, Cobra, Radio Shack, and Uniden detectors that manage to transmit radar-like signals that mimic POP bursts to an infuriating degree. They litter the airwaves with interference bursts on the same, exact frequency as, and similar duration to, a real POP-radar signal. Without some way of fending off these "J"unk signals, a detector would constantly nag its user with false alarms from these poorly designed "poluters" in other cars.
The common method of reducing the number of false POP alarms used by our competition is to reduce the sensitivity to POP signals (and their Junk kin) while leaving longer-lasting (over half a second) signals unmolested. This method requires reducing POP-radar range to line-of-sight-only distances in order to give enough relief from detector-generated false alarms to be worthwhile. I wasn't satisfied with only line-of-sight range for POP radar reception, so we pushed for a better solution.
I did nearly 10,000 miles of development driving, dodging speed traps and logging false alarm situations, while our engineers reorganised and optimised the false alarm rejection methods we finally chose. After lengthy deliberations, we realized that it was almost impossible to prevent every POP-like false alarm without taking too large a hit in POP-radar over-the-hill range. I decided that letting in a few POP-junk false alarms initially that were later announced to be "J"unk was less of a problem than not finding out about a POP radar until too late. I hope you'll agree."
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