JP1 Remotes

mitten58 · Joined: 23 Nov 2008 Posts: 34

My Cinema 7 just stopped working. That is, no light from the red (non-IR) LED, and it doesn't operate the TV, etc.

Exchanging batteries from an operable remote didn't help.

But.....connected to IR, it still uploads, and the remote's LED blinks twice to signal completion of the upload.

For curiosity's sake, what part of the remote's circuit is IR bypassing? The entire microprocessor?

(Looks like I'm in the market for a new remote. Atlas and Comcast types seem to be highly recommended lately.)

vickyg2003 · Posted: Mon Aug 03, 2009 9:55 pm Post subject:

My condolences. Cinema 7s are my absolute favorite remote.

The Robman · Posted: Mon Aug 03, 2009 10:09 pm Post subject:

Check to see if you have a button trapped in the ON position.
_________________
Rob
www.hifi-remote.com
Please don't PM me with remote questions, post them in the forums so all the experts can help!

mitten58 · Joined: 23 Nov 2008 Posts: 34

Thank you for the suggestion.

All of the buttons press down and spring back up. I even tried holding the remote upside down on the odd chance that one of the conductive pads had come loose and was resting on the circuit board. Nope.

Looks like this one is gone. Maybe I can salvage the memory chip for another remote.

The Robman · Posted: Tue Aug 04, 2009 9:41 pm Post subject:

The fact that the red LED blinks when you do an upload makes me believe the remote is still good. In most other cases when people have written posts like yours it has turned out to be a trapped button, so I'm surprised that that isn't the case this time.

Have you tried taking the remote apart and then putting it back together? The URC-7800 is one of the easiest OFA remotes to disassemble, I can separate the two parts of the casing using just my fingernails.

If you want, and are willing to pay return postage, I'll take a look at it, no guarantees of course.
_________________
Rob
www.hifi-remote.com
Please don't PM me with remote questions, post them in the forums so all the experts can help!

vickyg2003 · Posted: Wed Aug 05, 2009 5:41 am Post subject:

I saw that the LED wasn't flashing at all, I didn't read down to where the LED was flashing on reset.

mitten58 · Joined: 23 Nov 2008 Posts: 34

I had the remote apart, and went over it with a 10X loupe. Nothing unusual.

It managed to kill a set of fresh batteries in short order, so I suspect the electrolytic capacitor or one of the other discrete components has developed a leak.

I appreciate the offer for further assistance, but I think that I'll check the capacitor, or try hooking it up to a 6V transformer and see if something starts cooking.

If not, I'll look forward to picking out a new remote.

Thanks again.

Tommy Tyler · Posted: Mon Aug 10, 2009 4:37 pm Post subject:

This is an interesting problem. In the Cinema 7, one end of the red LED is connected directly to +6 volts and the other end to one pin of the processor via a small resistor. The two infrared LEDs are wired in series from +6 volts to ground through a resistor and a transistor. The transistor is driven by yet another pin of the processor. The two operate somewhat independently. That is, while the infrared LEDs are being pulsed at the carrier frequency to transmit a control signal, the red LED is turned on steady for visual feedback. And the processor flashes the red LED twice to let you know an upload or download was successful.

The very short life from a fresh set of batteries is an important clue. Yet if the main electrolytic capacitor were shorted there would not be enough voltage for the double blink. And if it is just very leaky, the symptoms should be very short useful life of fresh batteries, not complete failure.

I don't think the problem is failure of one of the components in the infrared transmitter circuit, because the processor would have no way of knowing that and so would still turn on the red LED during transmission. A hypothetical scenario might be that some sort of short circuit in the infrared transmitter circuit PREVENTS the processor from turning on the red LED by dragging the battery voltage low while trying to transmit. Since the transmitter is not trying to transmit during upload or download, it doesn't interfere with the double blink. This would also cause short battery life. Have you tried to tell if the remote is sending an infrared signal, such as by looking at it with the view finder of a digital camera or camcorder while pressing a button?

Many of us old-timers in the forum have a sentimental attachment to the Cinema 7, and hate to see any of them go belly-up. If you still want to try to salvage it, I'll keep thinking and suggesting. But I have to admit it does sound like something very serious, and if you've made up your mind I understand.

Tommy Tyler · Posted: Mon Aug 10, 2009 4:47 pm Post subject:

P.S.

You asked