Power Supply issue?

moosey

moosey

Member
Hi All,

One of my HDR-Fox-T2's has recently had an issue on powering up from standby.

Initially (a couple of days ago), for a couple of seconds, I got a message on a grey background saying "This channel is scrambled or unavailable" quickly followed by "No programmes are currently being broadcast on this channel". After a couple of seconds normal service was resumed and I could see the broadcast signal. This startup with the grey screen has increased in length over the last couple of days and has now got to the point where the grey screen doesn't go away by itself. I have to let the box "warm up" for a few minutes, re-boot and if I'm lucky programmes will be back.

I've tried switching off at the mains and re-starting but I still get the grey screen plus warnings.

I set up a couple of recordings last night and both failed (unable to track programme).

I was wondering if this is symptomatic of a PSU problem or something else.

Thanks,

Peter
 
Something else. More symptomatic of a low signal strength.
Please report Menu>Settings>Signal detection strength and quality.
Or on the Web I/F, Diagnostics > Mux Info. But bear in mind the latter is just as snapshot taken just after boot (I think)
 
Hi Trev,
Thanks for the thought.
Signal strength is fine. I am getting a good signal strength and 100% quality. In any case, no/low signal gives a different grey screen warning - "The receiver is not receiving a signal or the signal is too weak".
Peter
 
Then I give in. Wait for an expert.:roflmao:
But just one more stab in the dark.
Presumably you have checked that the box is actually tuned to the transmitter that you think it is, and that you have no channels in the 800's indicating it's tuned to multiple transmitters?
Could it be too much signal? You just said 'signal strength is fine'. What is your interpretation of 'fine' as indicated numerically on the box.
I get similar symptoms due to (I think) co channel interference (CCI) from the continent on occasions.
 
Hi Trev,

Signals from one transmitter only (Hannington) - see attached:
Hummy.jpg
The one channel I have in the 800s is due to Hannington having local services for both Reading and North Hants. My other Fox T2 has similar signal levels (fed from the same aerial) and is working fine.
 
moosey said:
I was wondering if this is symptomatic of a PSU problem or something else.
Click to expand...
Hard to say; I don't recall anything like this being reported before.

"Scrambled" generally means a data stream can't be decrypted (or attempts to decrypt it fail). The broadcast stream isn't encrypted, so this might be referring to the TSR buffer (which is). We are aware that the unit can appear to occasionally forget its encryption and/or decryption key (circumstances unknown, hypothesis unconfirmed), but I would expect that only to be cleared by a reboot and not of its own accord.

Try starting up without the HDD connected (so there is no TSR buffer) and see what happens.
 
moosey said:
Signals from one transmitter only (Hannington) - see attached
Click to expand...
Be aware this is only a snapshot indication of signal, taken at the time of retune. For a proper analysis of current reception conditions, only an extended live observation of each mux listed under Menu >> Settings >> System >> Signal Detection is sufficient (looking for momentary dips in the quality reading).

Further tools in the hidden service menu allow for examination of the function of each individual tuner - see
Things Every... (click) section 9.
 
Signal detection shows signal strengths are all in the 60% area apart from the two Local muxes which are 40% and 25%. Quality on all is 100%. Again, my other box from the same aerial and similar levels is working fine.
I did have a couple of re-boots on this box this morning as well. Whilst in the grey screen phase I can play previous recordings.

I'll try the box without HDD when I get a moment.
Cheers.
 
Hi All,
Previous recordings are all decrypted.

Just tried the box with HDD disconnected and no difference.
Whilst the lid is off I took a look at the PSU capacitors and no bulging seen.
Whilst a signal was being received I used some freezer spray to try to find any weak component(s) and all continued to work as normal. I even tried the freezer spray on the main board with the HDD/fan unit removed and again was unable to locate any weakness.
Put the box into standby for 10 mins and it started fine. I'll leave it fully powered off at the mains for an hour or two to let it cool down and try again.

Cheers,
Peter
 
moosey said:
Just tried the box with HDD disconnected and no difference.
Whilst the lid is off I took a look at the PSU capacitors and no bulging seen.
Click to expand...
I would be tempted to try swapping the power supplies between the two boxes to see if if the fault moves with the power supply.
 
Hi Martin,

That would be an idea, but at the moment the box has started to behave itself! After an hour+ of letting things cool off it is still starting as it should. Whilst the covers were off I did remove the HDD/Fan unit and disconnect/reconnect the cable between PSU and main board just to make sure it was seated correctly. With the HDD/Fan re-fitted all is working at the moment. I'll keep an eye on things and if it does become repeatable then a swap of the PSU boards would be useful to narrow down the problem.

To Black Hole - I did check the hidden menu and both tuners are reporting the same signal levels for each Mux.

Thanks,
Peter
 
moosey said:
Initially (a couple of days ago), for a couple of seconds, I got a message on a grey background saying "This channel is scrambled or unavailable" quickly followed by "No programmes are currently being broadcast on this channel". After a couple of seconds normal service was resumed and I could see the broadcast signal. This startup with the grey screen has increased in length over the last couple of days and has now got to the point where the grey screen doesn't go away by itself. I have to let the box "warm up" for a few minutes, re-boot and if I'm lucky programmes will be back.
Click to expand...
I occasionally see those message on SD channels but not long term and have just put it down to one of those Humax oddities.
moosey said:
Whilst the covers were off I did remove the HDD/Fan unit and disconnect/reconnect the cable between PSU and main board just to make sure it was seated correctly. With the HDD/Fan re-fitted all is working at the moment.
Click to expand...

Since reseating the fan seems to have helped it could be temperature related, do you have the Sysmon package to maintain a record of past temperatures?
It would also be worth installing the Fan package, for many users with the fan set to around 50% it is (virtually) inaudible and stops the disk ever reaching the alert temperature
 
Hi MymsMan,

Yes, I have got Sysmon and Fan packages already installed and over the past 30 days temperatures have never exceeded 40 degrees (Fan package set at 50%). Do you see these messages just at startup or at other times? I am seeing them on all channels, SD and HD.

After my box had a bit more time to cool down after this mornings activities the grey screen at start up has returned. I think that whilst playing around with HDD/Fan the unit was powered up long enough to cause the problem to eventually disappear. After a bit more rest/cool down time the problem has come back. I'll leave it a couple more days to see how repeatable it becomes before swapping over PSU boards especially as I don't have much spare time at the moment.

Luckily, this is happening on my secondary box that is generally used as a Freeview tuner for an older TV in the bedroom.

Cheers,
Peter
 
FWIW I get the "No programmes are currently being broadcast on this channel" message every time (IIRC) the machine is
rebooted from the WI or exiting maintenance mode and I don't think it's ever sorted itself out. A proper reboot the machine and all's well.
 
everthewatcher said:
FWIW I get the "No programmes are currently being broadcast on this channel" message every time (IIRC) the machine is
rebooted from the WI or exiting maintenance mode and I don't think it's ever sorted itself out. A proper reboot the machine and all's well.
Click to expand...
Unfortunately, when mine gets in this state even a full power cycle doesn't fix it.
 
Update.
An exchange of PSU boards between my two units shows that the problem is NOT with the PSU.
Use of a hairdrier and freezer spray on the faulty unit seems to indicate that the problem is on the main board with either the large component with the winged heatsink (microprocessor?) or IC parts immediately adjacent to it. I've run out of freezer spray so am unable to narrow down the problem part any further. In any case I would guess that there's not much I can do about it if this is where the problem lies.
Last night, from cold it took over 20 mins to warm up to a point where programmes were watchable, so it looks as if this particular box is not going to be of much use in the future and I will probably keep it for parts - at least the front panel and PSU seem to be fine and the enclosure is in good shape!
 
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