I believe the IR receiver in my satellite box has failed. Not really sure 100%, but since multiple working remotes fail to work with the box, and all components surrounding the IR device look fine, it seems to be the best place to start.
It is shown in the attached picture, middle device. It looks like a 3 legged device, surrounded by metal shielding. It may be that the IR device is not permanently attached to the metal shielding, but I will only be able to tell that when I desolder it, and I don't want to do that until I acquire a replacement. It is clearly marked -71Y4, but a search brings up no datasheet.
There seem to be some cheap offerings on ebay.
TSOP4838 looks just like it would without the shielding: 38 kHz Remote TSOP4838 DIP-3 IR Receiver Infrared Radiation Module GM | eBay
VS1838B is another, but very different in form: 10X Universal Integration IR Infrared Control Receiver TL1838 VS1838B Head FC | eBay
So, are these IR receiver devices all similar enough that I can try replacing with one of these above mentioned devices?
It is shown in the attached picture, middle device. It looks like a 3 legged device, surrounded by metal shielding. It may be that the IR device is not permanently attached to the metal shielding, but I will only be able to tell that when I desolder it, and I don't want to do that until I acquire a replacement. It is clearly marked -71Y4, but a search brings up no datasheet.
There seem to be some cheap offerings on ebay.
TSOP4838 looks just like it would without the shielding: 38 kHz Remote TSOP4838 DIP-3 IR Receiver Infrared Radiation Module GM | eBay
VS1838B is another, but very different in form: 10X Universal Integration IR Infrared Control Receiver TL1838 VS1838B Head FC | eBay
So, are these IR receiver devices all similar enough that I can try replacing with one of these above mentioned devices?
Attachments
Three leg IR receivers - ground, power, output. Aim a remote designed for the thing, and scope the output pin, do you see signal pulses appear? It may be working and the problem elsewhere. Your TV remote and your stereo remote don;t operate each other, and that is not due to the IR sensing transistor.
I bought one of those Chinese component testers for general use and when it arrived I found that it also has a remote receiver built in that displays the ID waveform of the handset plus another bit of waveform that changes depending on the button pressed.
I can find the web link for it if you are stuck.
I can find the web link for it if you are stuck.
The remote and box actually do work, just extremely poorly. The remote buttons have to be pressed repeatedly and for long periods of time, to the point of being unusable for practical use. I have not tracked it down for sure, but I see it as an analog failure mode related to IR receiving on what is mostly a digital piece of electronics, that's why I went there first. I have a scope but it won't be set up for a while.
Much appreciated but please don't go to that trouble. I won't be spending that much $$$ to fix this.
Oh. Well the first ten things on my list of possible causes are the up,down volume button, and the other ones you use most.
Most remotes use a rubber membrane for the buttons and they have conductive rubber contact points in each button that shunts across PC board traces on the remote board.
Chances are real good your remote board has gotten dirty over time and the black rubber contacts on the button sheet are worn. There are places online selling replacement remotes for most everything.
Sometimes a bit of alcohol and a Qtip helps. They do sell little bottles of stuff to dab on the rubber contacts to give them fresh surface.
Digital cameras, and likely the camera in a smart phone, respond to IR light as well as the visible band. They record the IR as red. SO if you aim the remote at the camera, and press a button, you should be able to see it on the camera screen. If it doesn't reliably blink with every push, then the remote is faulty.
Most remotes use a rubber membrane for the buttons and they have conductive rubber contact points in each button that shunts across PC board traces on the remote board.
Chances are real good your remote board has gotten dirty over time and the black rubber contacts on the button sheet are worn. There are places online selling replacement remotes for most everything.
Sometimes a bit of alcohol and a Qtip helps. They do sell little bottles of stuff to dab on the rubber contacts to give them fresh surface.
Digital cameras, and likely the camera in a smart phone, respond to IR light as well as the visible band. They record the IR as red. SO if you aim the remote at the camera, and press a button, you should be able to see it on the camera screen. If it doesn't reliably blink with every push, then the remote is faulty.
Kontact Chemie Graphite is what I use to repair remotes. Spray on a flat surface, dab a Q-tip on the liquid and touch /paint the remote membranes. Just touch them, if You put too much it will crack. But, first clean the remote PCB and the rubber. Use Isoprophyl alcohol.
To test remotes, Your mobile phone camera is Your friend. Of course it only tells You if the thing is emitting IR, not the waveform. Others use pencils to coat the rubbers.
By the way, IR receivers work at different frequency carriers 19KHz, 38KHz and Bang & Olufsen uses 56Khz I think, so You must use a TSOP for that frequency.
To test remotes, Your mobile phone camera is Your friend. Of course it only tells You if the thing is emitting IR, not the waveform. Others use pencils to coat the rubbers.
By the way, IR receivers work at different frequency carriers 19KHz, 38KHz and Bang & Olufsen uses 56Khz I think, so You must use a TSOP for that frequency.
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