dei tech tip 1923

Thanks to all for the help!

Some more info and a question... I just got a Clifford 50.7x which uses this antenna. I took the covers off and did some measurements. The red wire supplies 5v. The control center LED is connected to +5 thru a 200 ohm resistor on the circuit board, and draws about 6.5 ma. The pink wire is grounded by the brain to turn on the LED. The Grey wire is connected thru the button on the control center and a series 5K resistor to +5v. The grey wire goes to 4.17v when the button is depressed. This kind of surprised me -- I would have thought that the grey wire would be grounded when the button is depressed -- not sure why it is designed this way. Now my question, can I shorten the antenna lead without any detrimental effects to the units range? I've read somewhere that the antenna lead should be fully extended and not be bundled or coiled up, so I'd like to shorten it. Thanks.. Ed

Sure you can shorten it.  When DEI's antennas had actual coaxial cable, I did it all the time.  Why not!

However, with the design of the receiver being built into the antenna,  I think shortening the cable now is just to make it a cleaner install.

BTW, I've experimented with the straightened out verses bundled... Not in a car, but on a test board, and it yielded no different results.   Now in a car.. if the bundle was in a bad location (near some oscillator), I'm sure it could have some kind of effect.   But poor decision making like that would affect the rest of your install too probably

Thanks a bunch Mark! I was thinking along the same lines, the receiver is in the antenna and the antenna cable is just a 6 conductor parallel cable, I don't think it's even twisted pair. I would think that the cable is carrying digital signals to the antenna which then creates the broadcast radio signal, so shorter is better. I feel better getting advice from someones real world experience, thanks again. Regards.. Ed