From: utzoo!watmath!decvax!harpo!floyd!gjw
Newsgroups: net.auto
Title: Re:Radar Detectors
Article-I.D.: floyd.336
Posted: Wed Jun 30 14:01:32 1982
Received: Thu Jul  1 00:45:56 1982

        Over the last few years Car & Driver have been doing some very 
comprehensive tests of radar detectors. Unfortunately I can't recall the
dates of the issuses but they started their reports about four years ago.
I will breifly recap some of the things they've said and some of my findings:

	Radar detectors fall into two categories, passive detectors (some
RF engineers sometimes refer to them as video detectors) and superheterodyne
types. The passive detectors generally cost less than half the price of 
the superhet types but the performance of the superhets is of course much
superior. The police are allowed to use only two frequencies for their radar
units; the X band frequency 10.525 GHz and K band 24.150 GHz +/- 50 MHz
tolerance on each of the bands. These frequencies are assigned by the FCC
specifically for police radar and commercial intrusion alarms. Don't pay
attention to any balony a salesman may tell you about experimental bands.
The superhet detectors are tuned to the above frequencies  with a relative-
ly narrow bandwidth of a couple of hundred MHz. The passive types have much
wider bandwidths on the order of several GHz. These bandwidth differences
generally make the superhets less prone to giving false alarms. The superhets
have sensitivities that are about two orders of magnitude greater than the
passive detectors. This translates into a much greater range of warning to
contact with the radar source. However, this high sensitivity makes the 
superhets respond to distant supermarkets, stores, or warehouses with micro-
wave burgler alarms. The passive units are set off by a larger number of sources
such as nearby TV and radio stations and terrestial microwave communication 
links.
	I've had experience with both types of detectors. Four years ago
I purchased a Fuzzbuster II which has since then been superceded  by the 
model III. At the time it was a top rated passive unit and I've found its
range barely adequate for medium size and larger cars. At the time I was 
driving a small fiberglass bodied sports car (Saab Sonett III) and its per
formance was fine. Recently I purchased an ESCORT made by Cinncinati Micro-
wave and this unit, by any standards, is first class. It's been a top rated
unit by Car and Driver in their last two tests. The cost is $245 and it 
includes a very nice carrying case and handy visor clip. It is available
only direct from the factory by mail order so you don't pay any middlemen.
There are other superhet units available from electronic specialty stores
discounted into the $230 - $250 price range from Whistler, Fox, Bel, and
K40, but none of them approaches the features and quality of the ESCORT.
There is a new unit out by Fuzzbuster called the SUPERHET. Although its 
quality doesn't seem as good as the ESCORT it has the same features; vari-
able rate beep, volume control, automatic indicator light intensity adjust-
ment, signal strength indicator and city/highway sensitivity switch. If its
sensitivity is good it would be an excellent alternative to the ESCORT. I've
seen it dicounted to the $180 price range.
	The range at which a police radar can clock you is a function of a
car's radar profile. Larger cars generally have a greater profile and
vice versa. If you drive a small car a passive detector's sensitivity may 
be adequate for you. All the above mentioned manufacturers,except Cincinn-
ati Microwave also sell passive detectors. Most passive detectors can be 
found discounted to the $75 to $100 price range. The passive unit I would
recommend would be either the model III or ELITE made by Fuzzbuster. Elec-
trolert Inc. (the manufacturer of Fuzzbusters) is established and has a 
good reputation. I've had good experience with one of their earlier models
as I mentioed before. A good price for the model III is around $80 and for
the ELITE $100.


					Happy Motoring,
					Greg Wroclawski
					BTL  Whippany