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tom91ita
08-24-2004, 11:57 AM
i am preparing my 1985 honda CRX ITA/H5 car and want to know the advantages of the types of transponders. it looks like the direct wire is the best deal ($$).

is there a preferred location to install? any major advantages to the battery version?
any suggestions on the best place/region for deals?

tia, tom

Greg Gauper
08-24-2004, 12:30 PM
Go with the hardwired version and wire to your ignition switch, or fuel pump wiring, so that you can't forget to turn it on. You could wire it to the hot side of the kill switch since the current draw is very, very low (similar to the draw from a radio for storing preset channels).

joeg
08-24-2004, 01:02 PM
Greg is correct. Hardwire version all the way.

Make sure you fuse it, however.

Cheers.

Speed Raycer
08-24-2004, 03:36 PM
The only advantage I can see to the battery versions is if you're fielding multiple cars. Of course, if you're running multiple cars, you can probably afford to buy multiple hardwired Transponders http://Forum.ImprovedTouring.com/it/wink.gif

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bill f
08-24-2004, 04:58 PM
Greg,

Did you mean to say "hot side of the kill switch"? That would leave the transponder on all the time, would it not?

We solved the "multiple car" problem by identically wiring both cars. A simple two wire connector common between the cars allows the transponder to be easily removed from one car, and put into the second car in seconds.

Pick a cool, out of the way, location that is safe. Ours was a fab'd bracket just below the frame rail in the front of the car. It was able to pick up ambient cool air that bypassed the radiator.

Good racing.

Bill

[This message has been edited by bill f (edited August 24, 2004).]

Festus E. Simkins
08-24-2004, 05:29 PM
What size fuse should you use? http://Forum.ImprovedTouring.com/it/confused.gif I have installed mine but didn't fuse it. http://Forum.ImprovedTouring.com/it/eek.gif I think the fuse would kill a voltage spike and save the transponder. http://Forum.ImprovedTouring.com/it/biggrin.gif I bet they don't repair these things. http://Forum.ImprovedTouring.com/it/rolleyes.gif Probably just have to buy another one at $260+. http://Forum.ImprovedTouring.com/it/frown.gif


Drive well.

Greg Gauper
08-24-2004, 07:21 PM
Oops! I meant the switched side of the kill switch!!!!!! Car won't run if the switch is off, so you can't forget to turn the transponder on. The battery draw is very, very low so it isn't like it will kill your car battery (just like your stereo in your street car draws juice to retain the preset stations). If you are worried about the draw, it's easy enough to turn the kill switch off between weekends. A small 1 amp fuse is more than enough to protect the wiring to the transponder. Use one of those cheap in-line fuse kits.

[This message has been edited by Greg Gauper (edited August 24, 2004).]

RacerBill
08-26-2004, 08:45 AM
Tom: Having worked with electronic timing devices since they were first brought out to the Indianapolis Motor Speedway in 1989, I thought I would add my two cents worth. The easiest installation by far is the self contained model, just slap it in and go. No wires, no mess. Oh, did you happen to remember to charge it up before you left for the track? What do you mean, it's still on the kitchen (whatever) counter? Remember, I said the easiest, not the best.

As others have stated, the hard wired version is probably the most reliable (using connectors runs a close second, but you add the possibility that the transponder is in the wrong car - perhaps a pilot light on the transponder side to indicate that it is connected). The only bit of advice the I would add for the hard wired transponder is to be very careful routing the wires, avoid anything that could melt or rub the insulation on the wire and short out (We gave up on the wired ones at Indianapolis for that reason). Also, follow any directions that come with the transponder about placement. Just hooking it up to a battery does not guarantee a strong signal to the receiver loop.

Take care!

BMW RACER
08-26-2004, 03:59 PM
While on the topic of transponders, I have a question. How important is it to mount your transponder as far foreward as possible? I've heard conflicting responces.
Thanks.
John

apr67
08-26-2004, 06:12 PM
These are timing devices, not scoring.

Scoring is still done by hand.

So, it should not matter where on your car you mount the device.

dickita15
08-27-2004, 07:25 AM
Originally posted by apr67:
These are timing devices, not scoring.
Scoring is still done by hand.
So, it should not matter where on your car you mount the device.

In theory that is correct but stuff happens and it has happened where the scoring misses things so the transponder results are the only back up. I do not think it will ever determain a win but a race for 4th. it could happen. in my car if there was just not a good place to mount it the front i would not worry but all thing equal why not be safe.

a while ago the amb newsletter featured a cartoon of a vintage racer with the transponder velcroed to the dash and a slingshot for the last lap.
dick

RacerBill
08-27-2004, 08:17 AM
Regarding using transponders for scoring:

Again, fourteen years of experience yields hundreds of stories. In IRL (I can't speak for CART), the transponders are used for scoring as well as timing, with the location of the transponder defined in the technical specifications for uniform mounting. This rule was implemented after the Unser/Goodyear finish. The original calculation for the margin of victory was changed when it was discovered that Al's transmitter was located in the nose pod, forward of him feet, and Goodyear's was mounted in the side pod, about three feet back. Al was running a Galles chassis that year, and the nose was the only place we could put the transmitter where we could get a reliable signal.

Then there is the story about an event that took place on a weekday practice day. The track had gone yellow for debris and all the cars were in the pits. All of a sudden, the system recorded a car that had just turned a lap of something like 300 MPH! Not a car on the track at the time! Then another lap, and another. We were all standing in the scoring booth with our eyes bugged out and our jaws on the floor. Then we noticed a driver sitting on the pit wall, looking at his watch. At the appropriate moment, he leaned over the wall, and swung his arm, with a transmitter in his hand, over the timing loop! Good thing we were not feeding data at the time to a live broadcast company.

Hope everyone has a safe weekend.

Greg Gauper
08-27-2004, 08:52 AM
Two years ago I had a great race with Kevin Ruck at Road America. I crossed the line about two feet ahead of Kevin, but our transponders gave identical times. I kept that result sheet ( A margin of victory of 0.000 seconds looks pretty cool).

I have mine mounted on the engine side of the inner fender well, about 12-18" away from the front of the bumper. The location is safe and per the installation instructions, it has open space down and slightly forward.

I was at the June Sprints in 1979 when the FVee race finished in a dead heat. Dead Heats can and do happen.

Eagle7
08-27-2004, 08:57 AM
Originally posted by dickita15:
a while ago the amb newsletter featured a cartoon of a vintage racer with the transponder velcroed to the dash and a slingshot for the last lap.
dick
Now would you please come and wipe the coffee off my screen http://Forum.ImprovedTouring.com/it/biggrin.gif

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Marty Doane
ITS RX-7 #13
CenDiv WMR

apr67
08-27-2004, 11:49 AM
Mine is inside the shroud that protects/covers the fuel filter. Wired to the fuel pump or something.