HDMI handshaking

rpb424

Active Member
The missus and I both have identical HDR-Fox's.

A couple of months ago, hers started to have a problem in terms of the TV randomly saying 'No Video Input' when the source was switched over to it. Within the last week, mine started to have a slightly different problem whereby, every time it was started, the TV would display 'Video output not supported' until the vFormat button was pressed to force a HDMI handshake. In neither case did replugging the connections at either end have any effect.

The solution in both cases appears to have been a very simple one - dust in the machines! Her problem went away as soon as I'd had the lid off and blown all the dust out with an aerosol duster, and my problem has been fixed today in the same way.

Both HDRs must have HDMI circuitry that is somehow sensitive to our house dust, but I'm not convinced whether it is conductive in any respect or not.
 
Thin, and no more than you'd reasonably expect after several years. Certainly not thick to the point where it obscured anything below it on the pcb.
 
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The DTR-T1000 YouView box, which has some hardware similarities with the HDR-FOX, is notorious for HDMI failures and it has been reported that this is related to the processor getting hot: see here. Even a thin layer of dust would act as insulation. Even if this only made the processor a couple of degrees warmer it could make a difference. With custom firmware, you can install the fan package and keep the unit cooler in operation.
 
Yes, I've got custom firmware including the fan package, graphs show temperature usually hovers around 42degC, Fan off.
 
The catch with fan off is that parts of the box could be much warmer than wherever the temperature is being measured. Running the fan all the time at a low speed should help reduce hot-spots, even though the reported temperature may be much the same.
 
The temperature is taken from the disk stats. Silicon under a layer of dust could be much hotter locally.
 
Conscious that we're straying into custom firmware territory on the wrong forum (although the original issue did not relate to it), but I might be misunderstanding the terminology here.

When I say 'Fan off', what I mean is that my disk temperature graphs are completely shown in green, with the legend stating that green means 'Fan Off'. However, the 'minimum speed' slider in the fan package is set at 49%, so I would take that to mean that the fan never goes below 49%, but that would contradict the graph legend if 'Fan off' really means what it says.

The wiki seems a bit ambiguous as to how this is supposed to work

This utility allows the user to set a minimum continuous fan speed between 0% and 100%, By setting a minimum fan speed higher than zero it is possible to prevent the fan ever reaching the noisier 70% setting. If the Humax requests a higher speed setting, this higher speed will be used

First it states that 70% won't ever be reached, but then states that the Humax can request higher speeds (including 70% ?).

Am therefore not sure what fan setting is the best to use.
 
That quote is trying to say that by setting a minimum fan speed rather than letting the system turn the fan off completely (as standard), the system won't go through hot - fan on - cold - fan off cycles, eliminating the peak temperatures by using a user-defined "average" fan speed (with the compromise that it is never silent). Thus the fan should never (under normal circumstances) go to the higher (and noisier) fan speeds, but it will if increasing temperature warrants it.

However, you need to check whether the fan package is working at all (I don't know what the current situation is, but I recall a problem with it in the past), and whether the actual physical fan is working - but the detail of the Sysmon graph should give you enough information to deduce those. See Commissioning an HDR-FOX (click).
 
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The graph doesn't actually look at whether the fan is running. The different colours just reflect the temperatures at which the fan would run with the stock firmware (before the fan package).
 
That quote is trying to say that by setting a minimum fan speed rather than letting the system turn the fan off completely (as standard), the system won't go through hot - fan on - cold - fan off cycles, eliminating the peak temperatures by using a user-defined "average" fan speed (with the compromise that it is never silent). Thus the fan should never (under normal circumstances) go to the higher (and noisier) fan speeds, but it will if increasing temperature warrants it.

Thanks. I think your response reads better than the Wiki, the use of the word 'ever' being the confusing part and leading to what reads to me as a contradiction.
 
I trust that the fan has not been clogged up with dust. I once had a PC with a light coating of dust inside, but the fan filter & fan itself were totally encrusted in muck extracted from the air.
 
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