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Ok that looks easy, Lets give it a try !

Just a word before we start. This is a small circuit board. It requires tools ( soldering Iron/solder ) designed to be used on it. In this case HEAT is not your friend!! So tin the wire first! Clean the surface of the antenna carefully but thoroughly! Blow off all dust after cleaning. Then Tin the Antenna. Position the wire, then solder quickly. DO NOT leave the heat on the part long. Test your connection with an ohm meter. Place one test lead on the Antenna, Not the wire end soldered to it. Then place the other test lead on the free end of the wire. It should show Zero. If it does your good to go.

It comes apart well, as described. This is the case opened up.
IMGr_2165.JPG

Back side of board removed from case. Notice the membrane water shield.
IMGr_2167.JPG
This is what I used to hold the board. Fly tying anyone?
IMGr_2168.JPG
The back side with the water shield removed, exposing the antenna part labeled as XTAL
IMGf_2169.JPG
The antenna with 4 3/8 inches of wire soldered to it.
IMGr_2170.JPG
Wire and board back inside the water seal. ( Note: wire has to be thin or you will not be able to reassemble the case ) sorry about the wire color. It's all I had on hand that wire size laying around.
IMGr_2173.JPG

With all that done I ran a test to see how much Distance I gained.

I was able to operate the locks from 90 feet before the mod. I can now operate the locks from 125 feet before it gets iffy.

Is it worth it ??

Dom
 

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Nice DIY, Dom. How about tuning the antenna for resonance?

Can do !! V=FL Is the formula. Its the equation which ties together wavelength, frequency and velocity. In reality it would be L= 468 over F, f is the frequency. Or maybe I'm just rusty. I'll look it up. Or I could just cheat.
Do you know the frequency? I don't have my oscilloscope set up. The wife would go nuts, If i had all the stuff out on my desk.


Dom
 

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Oh, it's more fun to be an agent provocateur and leave the actual work to others. Besides, I think your scope is feeling neglected. :)


Uh.

And so am I!


Dom
 

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Fyi

That component that you soldered the wire to isn't the antenna.
That component is the crystal or ceramic oscillator chip. Almost
all car remotes work on the UHF frequency band so they’ll use a
loop type. antenna. Think of it as a small version of the old UHF
loop antenna on TV's.

1.JPG

I don’t think you can solder anything to this antenna loop without
detuning the oscillator circuit.
 

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That component that you soldered the wire to isn't the antenna.
That component is the crystal or ceramic oscillator chip. Almost
all car remotes work on the UHF frequency band so they’ll use a
loop type. antenna. Think of it as a small version of the old UHF
loop antenna on TV's.

View attachment 63391

I don’t think you can solder anything to this antenna loop without
detuning the oscillator circuit.

Thanks for that. The gain that I got must be from the Proximity of the additional wire going over the Antenna wire. I understood that the crystal clock oscillator Is what generates the proper frequency I thought that from the Vid, they had integrated the antenna into the case. As electronics get smaller, the parts integration becomes more prolific. I have been out of the industry for ten years now, so I am falling behind with development.

After looking at the printed board, I believe you are correct. The antenna loop is an integral part of the oscillator circuit. therefor adding wire to it would in in fact alter the impedance.

Nice Job.

Dom
 

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You might try capacitive coupling the new antenna.
Try hot gluing the wire in parallel to the antenna loop.

View attachment 63392

In essence I believe that's what gave me the 30+ foot gain in the transmitter distance.

Upon retest of the XTAL case, I find that it's not grounded.
So in reality that wire is not connected to anything.

That indicates that just by placing a wire inside the case, as you have shown does produce a small increase in overall transmitter signal propagation .

Dom
 

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It's nifty in theory...if I could just keep my doors from automatically re-locking before I get to the car. Maybe I could run...hahahahahaha.

I wonder if the receiver antenna could be extended.
 

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Without a schematic That would be imposable to answer accurately.
Page 130 of the electrical troubleshooting manual, just shows a box labeled " keyless receiver unit " . No specifics at all.


Some cars use the entire frame as an antenna. Others use the Radio antenna. Then just for no reason, others have one built into the receiver case. I have no clue what the design is for ours. If I took it apart and looked I may be able to figure it out. However the gain may work out to another minimal gain.

I just don't feel the need to do that.

Dom
 

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I was skeptical at first but it works.. heres a trick to try for yourselves if you think Im crazy. If you find yourself out of reach hold the key fob under your chin ( I tuck it in behind my chin above my adams apple) and TAH DAH.... I guess the theory is your skull acts as a funnel/ amplifier of the signal... I use it all the time and it works !
 

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I was skeptical at first but it works.. heres a trick to try for yourselves if you think Im crazy. If you find yourself out of reach hold the key fob under your chin ( I tuck it in behind my chin above my adams apple) and TAH DAH.... I guess the theory is your skull acts as a funnel/ amplifier of the signal... I use it all the time and it works !
far out, radio skull funnel!:cool:
 

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