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Garage Door Opener / Garage Door

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Speakerguy

Active Member
OK, so all of a sudden my wireless garage door opener operates intermittently. As in maybe once in every 20 times I push the button on the wireless opener it works. I opened it up, cleaned up some corroded contacts but no good.

Any ideas on what might cause all of a sudden such intermittent operation? I have a scope and can look at all the signals on the transmitter if need be, but there's also the possibility the problem is in the receiver.

Edited to add: The antenna? looks like a 1.25" long piece of 0.25" cardboard tube with two loosely spaced windings around it, and there is some small metallic thing inside the tube?

What sort of signal (and where) should I be probing to check the proper operation of the wireless transmitter? I figure these things are pretty generic, so if someone has worked with them before I'd appreciate any help.
 
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Speakerguy

Active Member
OK, so I probed the two loose turns of wire that are around the cardboard tube. I get a very nice 1.5Vpk-pk square wave that alternates between a low frequency square wave and a high frequency square wave, about 8 cycles of the LF square wave then transition to 16? cycles of the HF wave. At 200uS/div I get two full cycles of the lower freq waveform and 4 cycles of the higher freq waveform per division.
 

user_88

Member
Just a thought or two....

Have you had any serious line voltage phenomena lately? .... lightning strikes ..... power outages?

Sometimes the MOVs on the receiver boards are insufficient, particularly if the receiver is several years old.

If you open the receiver unit, is there any sort of adjustment device? This might be a variable capacitor with an aperture for a screwdriver type tuning tool ... or a small dial of some sort. If you find any component that looks like it is adjustable, first make a pair of reference marks with a sharpie pen or something similar.... then try small adjustments either way to see if you obtain an improvement.

Is there any adjustable component on the transmitter board?
 

HiTech

Well-Known Member
What brand of opener is it? Often the receiver modules fail and most of them can be easily replaced with a screwdriver and a ladder. Have you tried visiting the mfgr's website under the customer support category?
 
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