'Power on' problem with PVR

[Offside13]

Hello - For some time I've had a minor problem with a PVR unit that refuses to power on by remote control. It's obviously not a problem with the remote itself as the original has had to be replaced by a programmable Logitech one that sees the same issue. Everything else works perfectly, including being able to turn the PVR off from the remote.

The simple description of he problem makes me think that there could be a relatively simple solution, however I'm definitely an electronics novice. Can any of the clever people here give me some optimism and suggest how they might go about investigating/fixing?

Thanks in advance! Sarah

 

[kneegrow]

hook up your logic analyzer to the IR receiver

 

[Offside13]

"Thanks"

 

[quantumtangles]

I am not one of the clever people here but if you tell us the model name and manufacturer of the unit we may be able to help.

Sometimes the 'mode' a unit happens to be in can prevent remotely turning the power on (for example, a combined DVD and VCR unit may appear to be unresponsive via remote control because it is necessary to switch from DVD mode to VCR mode or vice versa to enable the relevant 'power on' function remotely).

If you provide more information, serious minds may be able to help

 

[Offside13]

Thanks very much for this, quantumtangles. The PVR is a Sagem DT6400.

I would hope that I'm not being so blonde as to miss something really straightforward like a mode change. The only issue is trying to power it on from the remote control, and even then it gets weird.

In its normal 'on-but-off' state, the time is displayed. if I want to turn it on, e.g. to see the EPG and set up a recording, I have to press the power button on the machine itself - the remote power button does nothing. However, with existing timer recordings having been set up, the Sagem will switch itself on at the appropriate time, without any intervention from me being necessary. The remote power button always works to turn the machine off.

Hope any of this helps. It's more of curiosity than a problem to me by now, the PVR does everything it should do apart from this one minor flaw.

 

[quantumtangles]

Thanks very much for this, quantumtangles. The PVR is a Sagem DT6400.

I would hope that I'm not being so blonde as to miss something really straightforward like a mode change. The only issue is trying to power it on from the remote control, and even then it gets weird.

In its normal 'on-but-off' state, the time is displayed. if I want to turn it on, e.g. to see the EPG and set up a recording, I have to press the power button on the machine itself - the remote power button does nothing. However, with existing timer recordings having been set up, the Sagem will switch itself on at the appropriate time, without any intervention from me being necessary. The remote power button always works to turn the machine off.

Hope any of this helps. It's more of curiosity than a problem to me by now, the PVR does everything it should do apart from this one minor flaw.

Sometimes, pressing (remote control) buttons other than the power button can bring a device out of standby. It can appear to be a common problem with remotely controlled Televisions... they do not respond to the 'red' power on button on the remote, but spring to life when a channel button is pressed on the remote (e.g. channel 1, 2 or 3 etc). If this is not TV remote control power syndrome, it may be a software issue.

In that event, download latest updated software from the manufacturer's website. No obvious schematic for your machine but there is probably going to be a USB connector attached to the motherboard. Load updated software via the USB and check again for the anomaly.

Another possibility is the infrared LED at the top of the remote control is not (for some reason) working when you press the power button. If you have a photosensor (light sensitive diode for example) in your parts bin, you may be able to check this. Hope this helps

 

[Offside13]

...it may be a software issue.

In that event, download latest updated software from the manufacturer's website. No obvious schematic for your machine but there is probably going to be a USB connector attached to the motherboard. Load updated software via the USB and check again for the anomaly.

OMGOMGOMGOMG!!!!!! You did it, QT!!! Thank you, thank you thank you so much!!!

After years of assuming, with plenty other Sagem users, that they had forgotten about this old model when doing firmware updates, an over-the-air one was offered at Christmas. i refused it, just in case it did anything catatstrophic before I could watch or backup all the recordings.

Too curious to resist seeing if your suggestion might be right, so I downloaded and I installed the firmware via USB - et voila, it works! Twice I've tried it and it works!!

So after years of grumbling about the back-breaking, humanitarian crisis of having to get off my backside to switch the PVR on, it's cured. I can now spend days fighting with the programmable remote to get it to talk to another box.

Thanks again so much QT, you are a gentleman and scholar!

 

[quantumtangles]

Most welcome. Lucky guess on my part