How to fix circuit board for wireless garage door opener

Thread Starter

kje

Joined May 6, 2012
27
What component is this on the circuit board for my wireless garage door opener? I tried to solder it to the board but it seems that I have to buy a new component.

What component is this and what can I search on ex Ebay?
20190907_133038.jpg
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
+1 on the 26mhz xtal.
27Mhz is an old common freq. for remote control uses, now modern openers for garage doors, typically use a much higher frequency.
Max.,
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
If you cannot find the exact xtal, and that receiver just ends up with a relay contact-closure, I picked one up on ebay for $6.00, key fob transmitter and 4 channel receiver.
There is also single channel if needed.
You just need 24vdc for the 433Mhz receiver.
Max.
 

MisterBill2

Joined Jan 23, 2018
18,167
That device is indeed a crystal, it appears to be for setting the local oscillator frequency for a CB receiver with a 455 KC IF (intermediate frequency). The brand is "NDK", a company that is still around. You may be able to recover a replacement from an old early 23 channel CB radio, but you may need to order one from a crystal company. That will cost about $10 if you are not in a rush.
From what I see of the circuit board it appears that it is a higher quality system, worth repairing. And it is probably a much better quality than anything made currently for the consumer market.
 

DickCappels

Joined Aug 21, 2008
10,153
The 23 channel rigs used crystal frequency synthesizers, beating different crystals together to get 23 channels from 11 crystals, none of which are the same frequency as any channel. Best to order the 26.540 MHz crystal or as MaxHeadroom suggested upgrade to a modern transmitter and receiver. The later might be a better choice because after changing the crystal it might be necessary to fine tune the oscillator or worse, the IF strip if the oscillator cannot be fine tuned. How would you do that unless you are lucky enough to have the right equipment?
 

MisterBill2

Joined Jan 23, 2018
18,167
I have at least one older CB radio that has crystals for each channel. Yes, the later versions used crystal mixing and it worked fairly well, but the very first 23 channel ones were less optimized.
But if the crystal is available from Mouser then that would be the way to go. There might be a need to tweak the alignment for maximum range, as a worst case possibility.
If the TS can show us a picture of the whole circuit board then it should be possible to provide additional correct advice, rather than best guesses.
 

Dodgydave

Joined Jun 22, 2012
11,284
That device is indeed a crystal, it appears to be for setting the local oscillator frequency for a CB receiver with a 455 KC IF (intermediate frequency). The brand is "NDK", a company that is still around. You may be able to recover a replacement from an old early 23 channel CB radio, but you may need to order one from a crystal company. That will cost about $10 if you are not in a rush.
From what I see of the circuit board it appears that it is a higher quality system, worth repairing. And it is probably a much better quality than anything made currently for the consumer market.
There must be a Chip on the other side, to encode the signal for the receiver.

Newark do Xtals usa.
https://www.newark.com/abracon/ab30.../Element14_US/c/crystals-oscillators/crystals
 

MisterBill2

Joined Jan 23, 2018
18,167
Really, there must be quite a few parts on the other side of the board. And a replacement crystal should be installed with the leads a bit longer to avoid a repeat of the incident that resulted in the destruction of the crystal. And I hope that the remote transmitter is in good condition, since those often suffer abuse bouncing around in a car or a pocket.
 

jpanhalt

Joined Jan 18, 2008
11,087
Sounds interresting. How do I know It will work with 433 mhz and how do I power it?
I think this is a good indication it twill work with 433 MHz:
upload_2019-10-12_15-17-53.png

As for the 12 V power, you need to know what available on your motor unit. There is probably 12 V there (if still working) or get an equally cheap mains power to 12V wall wart and plug it into or attach it to the motor supply.
 

MisterBill2

Joined Jan 23, 2018
18,167
OK folks, connecting a circuit board receiver and a wall wart supply could possibly work, BUT the typical garage door opener installation would make that addition a pain. Replacing a broken crystal will allow using all of the original hardware mounted in it's original location with the same wiring and the same code. THAT lack of pain is sort of important. Even if the crystal cost a fair amount more it is the way to go, if the rest of that receiver is working.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
OK folks, connecting a circuit board receiver and a wall wart supply could possibly work, BUT the typical garage door opener installation would make that addition a pain. Replacing a broken crystal will allow using all of the original hardware mounted in it's original location with the same wiring and the same code. THAT lack of pain is sort of important. Even if the crystal cost a fair amount more it is the way to go, if the rest of that receiver is working.
Still old technology and the old, un-encoded, 72Mhz was open to spurious opening from other sources.
The old RC frequency!
Max.
 

MisterBill2

Joined Jan 23, 2018
18,167
Still old technology and the old, un-encoded, 72Mhz was open to spurious opening from other sources.
The old RC frequency!
Max.
OK, Max, but given the crystal frequency, 26.540, the transmitter is probably on the CB radio control channel "A". And we don't have much information on what part of the world the TS lives in. And some governments are not very patient with those who use unauthorized frequencies.
 
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