[injectorman]

Hi Guys.
Ive just had the RF looked at on the car decoder.

a)The antenna should be as vertical as possible with a slight kink in the middle.

This will mean it needs to pass up and into the cockpit in most cases.

b)The antenna length remains the same at 28mm. Somehow some escaped into the wild at 34-39mm! Just trim to 28mm.

c)No need to pass antenna to outside of car. This is not recommended and also to retain car aesthetics.

d)The antenna tip should not be near the motor. and clear (on top of) any other wiring.

Rick

 

[injectorman]

QUOTE (h00ch @ 4 Feb 2012, 03:29) <{POST_SNAPBACK}>Before I start trimming my antenna, I just wanted to make sure about the length. Should the length of 28mm be measured from the top surface of the chip to the tip of the antenna, or should the 28mm length also include the antenna wire that is soldered into the chip?
Good question, 28 mm from surface of PCB.

QUOTE (Merc_A @ 4 Feb 2012, 05:56) <{POST_SNAPBACK}>In cars having no issues, i have followed the rules like pointed out in the beginning: straight as possible, away from the decoder in a straight angle, away from the motor, no wires (metal) on top of the antenna.

With cars having lap counting issues, I have experienced better reception (that is to say, no more missed laps) after repositioning the car decoder antenna.
In most cars, i managed to position the antenna (sort of) to shape D: straight up, then a slight bend into the cockpit.
In this way, the antenna tip would be higher than any metal part or wire in the car.

It seems like some cars are very forgiving when it comes to antenna positioning, others very demanding.
My Ninco Mosler kept having issues until i positioned the antenna straight up, into the cockpit. My SCX Bugatti however, is on the inside crowded with wires and stuff, the antenna lies suboptimal in the car but it has not missed a single lap - and it has made quite some laps the past weeks.

I have three questions:
1. How come this new advice - out of testing, empiric / experience, or some other source?

2. it try to understand why the antenna length is so critical for good reception - will a too long antenna have distorted reception / broadcasting? I'm not into R/F tech knowledge, but i'd like to understand it.

3. My english fails me at times: what exactly is a kink in the middle? shape A (straight up, then somewhere 90 degrees bend), B (small S or Z shape), C (big S or Z) or D (like i have in most cases)?

Merc

Hi Merc,
1. I had Seppo take another look to be sure thats things are optimised.
2. 28 mm is simply the optimum length, but will work on other lengths to a lesser quality
3. D is the one youre after.

Cheers
Rick

 

[injectorman]

Hi Guys,
Any demand for an insulated car decoder? ie cannot short out anywhere? I can now clear gel coat car decoders with a non corrosive material. Iy looks neat too.

Rick

 

[injectorman]

Hi Guys,
Any demand for an insulated car decoder? ie cannot short out anywhere? I can now clear gel coat car decoders with a non corrosive material. Iy looks neat too.

Rick

 

[injectorman]

Hi Guys,
Any demand for an insulated car decoder? ie cannot short out anywhere? I can now clear gel coat car decoders with a non corrosive material. Iy looks neat too.

Rick

 

[injectorman]

....or do it yourself
Manufacturer: Dow Corning
Description: "3140 RTV Coating'" " Non Corrosive silicone rubber flowable".
Part No: 5 948 920 010

My advice just try one and test for a while before going over all your chips.

Rick