OT: Keyfob transmitter broken.

[DSpeck]

Since this is where the technical electronics types hang out, I thought I'd ask this here... /ubbthreads/images/graemlins/wink.gif

I have a Chrysler car, with a remote that doesn't work. One of the components in the remote has a broken lead, and I think it's the transmitter. I can easily replace the component, but I don't know what it is, or where to get a new one... /ubbthreads/images/graemlins/frown.gif There is a picture here of the circuit board. The component in question is the large round one at the top of the board. The component has 3 leads, one of which is not used, and one of which hass broken off flush, such that I can't solder onto it.

My questions are these:

What is the component?
Who makes it (that stylized M)?
Where can I buy a new one? /ubbthreads/images/graemlins/wink.gif

Thanks! /ubbthreads/images/graemlins/smile.gif

Doug.

 

[brickbat]

Without seeing the entire PCB, I can't be sure, but it might be a SAW resonator. These are used to control the frequency of the transmitter oscillator and I've seen them packaged in this type of case. Also, the '315' on the part is a clue, as 315MHz is a very common frequency for remote keyless entry in the USA. I don't recognize the logo, but RF Monolithics, Inc makes similar parts. Check their p/n RO2073, for example. http://www.rfm.com/RFMhtmlie.htm

 

[paulr]

Not sure but I think that part might be an xtal or xtal oscillator. Easiest is probably get another remote on ebay.

 

[gwbaltzell]

I'm fairly sure its a SAW filter at 315.000 Mhz like this one (in pdf). I was thinking the symbol was used by a company called Matek of Mastek or some such but the closest I can find was on this Russian site is for Matsuo Electric which does not show SAWs in their current product line.

 

[paulr]

Looks like you can get those transmitters for a few bucks on ebay.

 

[DSpeck]

I think I'll just get one off ebay - unless someone knows for sure the replacement part?

 

[louie]

I think the logo is Matsushita (Panasonic). If they are SAW resonators, an old Digikey catalog shows 315 MHz SAW resonators from Panasonic, but the current catalog shows the 315 MHz units as non-stocked. Also, there are 1 port and 2 port versions (beats me).

Digikey part no. for 1 port is PX315S1-ND; 2 port is PX315S2-ND

Digikey PDF of SAW resonators, but no 315MHz stocked (very end of page 699)

OK, doesn't help you buy one, I guess ebay is still the easiest.

 

[gwbaltzell]

I think ebay would be the easiest. Murata (no, they use an italic M) has this sheet that talks about one port SAWs. And there is the possibility this is a two port that had one leg deliberately clipped to use as a one port! Likely if the reciever uses a two port, so they only had to stock one part for both.

 

[snakebite]

that is a s.a.w and is a matsushita(panasonic) part.
should be easy to find a distro that has it.

 

[gwbaltzell]

Well, it is Panasonic. However, they discontiued their metal can SAWs 4 years ago. Only surface mounts. Would either have to salvage one, find new old stock, or find an equivalent from another maker.

 

[DSpeck]

Thanks for finding out for me, guys. /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/thumbsup.gif I have put a bid in on an original remote on ebay, and I'll probably just transplant it from the new board to the old one. It saves reprogramming the remote & car.

 

[PlayboyJoeShmoe]

On a similar note, the remote to my (sister's) '95 Lincoln Town Car won't lock the car/set the alarm anymore. The other buttons still work.

What Is involved in getting a new fully functioning remote???

 

[PhotonWrangler]

[ QUOTE ]
PlayboyJoeShmoe said:
On a similar note, the remote to my (sister's) '95 Lincoln Town Car won't lock the car/set the alarm anymore. The other buttons still work.


[/ QUOTE ]

That's gotta be a bad contact under the button. If the buttons are the type that are molded into a single rubber sheet, you might be able to transplant the whole sheet from another broken remote. If the contact pads aren't actually broken, it might come back to life with a simple cleaning of the contacts.
/ubbthreads/images/graemlins/thinking.gif

 

[PlayboyJoeShmoe]

But we got the car a little over a year ago with two remotes. One died completely, batteries nor anything else would help.

If this one goes down completely, then what? And the point of my question was how do I get a new remote?