RM-F04 remote not working

A

aod

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My Humax RM-F04 remote has (mostly) stopped controlling my HDR-Fox T2.

The remote does continue to control my Philips TV.

I have replaced the batteries with brand new ones, and tried leaving the remote with the batteries out for 5 mins to see if this helps reset it.

I have found if I put the remote very close to the Humax PVR (almost touching) it does work intermittently.

I have powered off the Humax at the switch on the rear for 5+ mins, but that didn’t make any difference.

Can anyone suggest what the problem may be, and how to fix it?
 
aod said:
My Humax RM-F04 remote has (mostly) stopped controlling my HDR-Fox T2.

The remote does continue to control my Philips TV.
Click to expand...
This sounds more like the IR sensor on the Humax front panel failing rather than the remote.

If possible borrow a remote (from any humax product) or try a universal remote to see if it responds to them.

If you install the customised firmware and web interface you can use a PC or mobile phone as a remote control.
 
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MymsMan said:
This sounds more like the IR sensor on the Humax front panel failing rather than the remote.

If possible borrow a remote (from any humax product) or try a universal remote to see if it responds to them.

If you install the customised firmware and web interface you can use a PC or mobile phone as a remote control.
Click to expand...
Ok thanks a lot! Not sure I know anyone with a Humax remote to borrow from, however is it possible to replace the IR sensor in the unit? Thinking about it, the remote does seem to have been getting less responsive over the last few years - even after changing batteries - however it could just be the sensor, like you say.

I'm fairly confident with electronics and replacing components, so it might be an option to do this if the parts are available.
 
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MymsMan said:
replacing the entire front panel might be easier - spares might be found on ebay from those selling for parts or on the dead humax thread

I would still wish to confirm the sensor is at fault before taking the panel apart. whereabouts do you live - you might find another local forum reader,
Click to expand...
Currently there is a compatible panel from a DTR-T1000 going for £8 including P&P.

https://www.ebay.co.uk/itm/185297360160
 
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Maybe there's a big dead spider blocking the front panel IR reception..
Also check
your TV receives IR ok - eg VOL+, VOL- , mute, P+, P-, all numeric keys etc (may confirm functioning remote keys)
try same key patterns against the HDR - after blocking/shielding the HDR from everything else
try the front panel buttons to see if they work ok.
Comparing test results should give you an idea of what to check or test next.
 
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MymsMan said:
There is a guide to disassembly https://hummy.tv/forum/threads/hdr-fox-hardware-commissioning-disassembly-repair.5728/

I don't know if the ir sensor is easily replaceable, but replacing the entire front panel might be easier - spares might be found on ebay from those selling for parts or on the dead humax thread

I would still wish to confirm the sensor is at fault before taking the panel apart. whereabouts do you live - you might find another local forum reader,
Click to expand...
Thanks, I'll take a look, although like you say I need to 100% confirm the issue first of all.

I'm in west Norfolk, if anyone local happens to be able to help
Luke said:
Currently there is a compatible panel from a DTR-T1000 going for £8 including P&P.

www.ebay.co.uk

BT Humax DTR-T1000 YouView Replacement Front Bezel With LCD Display & Buttons | eBay

Find many great new & used options and get the best deals for BT Humax DTR-T1000 YouView Replacement Front Bezel With LCD Display & Buttons at the best online prices at eBay! Free delivery for many products!
www.ebay.co.uk
Click to expand...
Cheers, that's useful, I'll bear it in mind
bottletop said:
Maybe there's a big dead spider blocking the front panel IR reception..
Also check
your TV receives IR ok - eg VOL+, VOL- , mute, P+, P-, all numeric keys etc (may confirm functioning remote keys)
try same key patterns against the HDR - after blocking/shielding the HDR from everything else
try the front panel buttons to see if they work ok.
Comparing test results should give you an idea of what to check or test next.
Click to expand...
Good point about the blockage.

I have previously checked that the TV receives IR ok as use the Humax remote for this most of the time anyway. I can control the vol/channel/power etc for the TV using the Humax remote.

The HDR doesn't receive IR signals unless very close. as mentioned. The Front panel buttons do work fine.
 
There is an alternative or temporary solution - install the custom firmware and IR for the WebIf https://wiki.hummy.tv/wiki/WebIf_Remote_Controller
From your description the remote physically works - but can't tell which end has the fault.
Is it the handset transmitter struggling to send the correct IR signal (to the HDR) or the receiver not able to interpret it?
 
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bottletop said:
From your description the remote physically works - but can't tell which end has the fault.
Is it the handset transmitter struggling to send the correct IR signal (to the HDR) or the receiver not able to interpret it?
Click to expand...
It doesn't seem very likely that the handset is faulty. I might be prepared to postulate it had "forgotten" the HDR codes or was set to the wrong control channel if it didn't work at all, but working sometimes rules that out.

That it controls the TV indicates the handset hardware is fine, so that leaves the HDR IR receiver or downstream. Installing CF will provide more diagnostic opportunities.
 
aod said:
I'm fairly confident with electronics and replacing components, so it might be an option to do this if the parts are available.
Click to expand...
In that case you could try fitting a new sensor. They are readily available from Ebay (from £1.30 including post UK seller).
You need a VS1838/TL1838 this has the correct pin out.
 
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This is a close-up of the IR receiver on the front panel circuit board. It looks fairly straightforward to replace, although the metal shroud will need some fiddling with (and is bespoke).

(Not having done it myself) I suggest the easiest way would be to cut the legs of the old device with everything in situ, high up, and see if it can be extricated without having to remove the shroud (which could be tricky). The remaining legs will then be easier to remove from the PCB one at a time, or could be left in place and the new part soldered to them.

...But it also occurs to me this might be another example of capacitor rot.

F0E5DADD-2992-442F-B8A0-0B8A1E429744.jpg
 
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Black Hole said:
...But it also occurs to me this might be another example of capacitor rot.
Click to expand...
You may be correct.

I have just checked the circuit, the sensor is powered from the 5v supply via a 100 ohm resistor and decoupled by a 47uF capacitor, if the capacitance value reduced it could cause these symptoms.
The fact that aod said "Thinking about it, the remote does seem to have been getting less responsive over the last few years" could be another clue.

Checking the in-circuit ESR reading on mine = 8 ohms this is poor for a 47uF and does, as BH suggests, lead to it being another suspect capacitor and a possible source of problems and would be worthwhile replacing first.


Edit: In the datasheet for the IR receiver the recommended capacitor value is 100uF.
 
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Stummery said:
Checking the in-circuit ESR reading on mine = 8 ohms
Click to expand...
How did you measure that with the cap still in circuit? Some exotic tester or just a multimeter? If the latter, how have you accounted for other current paths, particularly through the IR receiver chip? Or is it conventional wisdom that semiconductors don't turn on at the test voltage?
 
I use an EDS-88A CapAnalyzer (from USA) that is designed for in-circuit capacitor ESR testing and uses less than 50 millivolts.
As you can see a 47uF ESR at 8 ohms is well into the red part of the chart! So I shall be replacing mine.

Edit: Measuring my capacitor value out of circuit reads 26uF and the remote control range was about (12 feet) 4 metres.
So it suggests that BH's theory that this is a capacitor to suspect, especially if your remote control range reduces, is correct

(not my photo)

EDS-88A.jpg
 
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Stummery said:
I use an EDS-88A CapAnalyzer (from USA) that is designed for in-circuit capacitor ESR testing and uses less than 50 millivolts.
Click to expand...
Also, I now realise that as high is bad, if there are other current paths the ESR test would give a false negative (pass) rather than a false positive (fail).
 
Correct, that is why the EDS-88A does a low voltage DC resistance test first. As you say capacitors and other components can fail low resistance/short circuit as well.
 
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aod said:
The HDR doesn't receive IR signals unless very close. as mentioned
Click to expand...
Coming in late on this, this has the feel of there being another pulsed IR source in the room. I've not read through this entire thread but it would be easy enough to check by testing the HDR in another room.
 
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I'm also coming in late, but it may be useful to know that the camera sensor on the average smartphone is sensitive in the infra-red spectrum. You can point an IR remote at the camera, press buttons on the remote and check that IR is being sent. I've also used this to determine exactly where on the remote the IR LED sender is, in order to clean the right area.
 
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Andrew Benham said:
it may be useful to know that the camera sensor on the average smartphone is sensitive in the infra-red spectrum
Click to expand...
Smartphone camera sensors now typically include an IR-blocking filter (so as to produce a more natural colour reproduction), so don't rely on it and always compare with a known working IR source. My Apple iPad Pro Mini MM192B/A (for example) shows up IR with the selfie camera but not the rear camera.

From Things Every... (click) section 13:
Black Hole said:
To test whether a handset is transmitting when expected (and not when not expected), view the emitter with a digital camera (eg the camera on a mobile phone). Digital cameras (not all - check with a known working remote) are sensitive to IR (Infra-Red) and the flashes will show up in the viewfinder (electronic, not optical). The iPad3 rear camera is not sensitive to IR but the front one is, so this is my favourite way to test IR handsets because it is like an IR-vision mirror.
Click to expand...
 
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