Beyonwiz T4 set top box suddenly cannot see any channels (and 1 tuner disappeared)

[michal]

Suddenly as of this morning my Beyonwiz T4 set top box cannot see any channels and only has three tuners (A, B and C with D missing).

A location scan finds no channels and the antenna is working as I get DVB-T channels if I plug directly into the TV. I also tried plugging the antenna directly into each tuner.

I was unable to find any troubleshooting for this on the website. Does anyone here have any suggestions

Thank you.

[MrQuade]

Suddenly as of this morning my Beyonwiz T4 set top box cannot see any channels and only has three tuners (A, B and C with D missing).

A location scan finds no channels and the antenna is working as I get DVB-T channels if I plug directly into the TV. I also tried plugging the antenna directly into each tuner.

I was unable to find any troubleshooting for this on the website. Does anyone here have any suggestions

It's likely to be a problem with the regulators that feed the tuners on the T4's motherboard and is a known issue with the hardware once it reaches a certain age.

It is however more common to loose two tuners (either A&B or C&D), so I am not sure how you lost just one in this case, but I think it is still likely the same problem.

You can do some troubleshooting by connecting the antenna to Tuner A, and then making sure Tuner A is the preferred tuner for Live viewing, and changing channel to ensure that the T4 is trying to use Tuner A. Then plug the antenna into Tuner B, and set the T4 to use Tuner B as preferred for Live viewing and change channel. Repeat for Tuner C.

That will test each tuner in turn and tell you if only some or all are dead.

Either way, I think you will need to contact either Beyonwiz or Warkus for a repair. Operating the T4 with dead regulators is VERY bad for it, and should be avoided, as the problem is likely to spread and eventually become irreparable.

[michal]

This post goes into some detail regarding replacing the regulators. viewtopic.php?f=53&t=12841

I'm not sure if I was measuring at the right point but the two regulators that protrude from under the heatsinks gave me a reading of 3.3v. One heatsink is certainly warmer than the other.

I had already tried each tuner directly and didn't get any to work. Might they be interfering with each other as suggested in the regulator replacement post?

Logs show a lot of this error looping:

Code: Select all

{2235}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 
{2235}[SemcoAPI_TDA18250A_Tune] (0) err: 270413833
{2235}[DNOQ44QAH109A_TuneTer] (0) SemcoAPI_TDA18250A_Tune fail.
{2235}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 

I'll take any tips I can get.

[MrQuade]

I had already tried each tuner directly and didn't get any to work. Might they be interfering with each other as suggested in the regulator replacement post?

No worries. You only mentioned that you had connected to each tuner, but didn't say if you had manually configured the T4 to use each particular tuner as you were testing. I just included that measure to be sure you'd tested properly.

The most blunt approach to rule out a software issue, is to re-load the firmware from USB.
If that doesn't work, then it boils it down to your T4's tuner or tuner regulators being bad and the unit will need repair.

[michal]

I rebooted again and it's just dropped down to two tuners (A and B).

Logs at boot include:

Code: Select all

DVB: registering new adapter (dvb)
{138}[SemcoAPI_TDA18250A_Init] (0) tmbslTDA18250A_HwInit err: 1
{138}[DNOQ44QAH109A_Open] (0) SemcoAPI_TDA18250A_Init fail.
{138}[SemcoAPI_TDA18250A_Init] (1) tmbslTDA18250A_HwInit err: 1
{138}[DNOQ44QAH109A_Open] (1) SemcoAPI_TDA18250A_Init fail.
dvb dvb.0: DVB: registering adapter 0 frontend 0 (DVB-T/T2 NIM)...
dvb dvb.0: DVB: registering adapter 0 frontend 0 (DVB-T/T2 NIM)...
BKNI_P_GetTrackAllocEntry_resize: resizing from 5376->8704
BKNI_Malloc(linuxkernel) top users:
    blocks,   bytes, filename:line
       915,   54900, nexus/base/src/nexus_base_scheduler.c:451
{236}[ioctlVideo_SelectSource] (0) stream_source (0 -> 1) 
{236}[ioctlVideo_SelectSource] (0) stream_source (1 -> 0) 
__clk_enable: network [1]
bcm7425_pm_network_enable 00
__clk_enable: enet [1]
bcm40nm_pm_genet_enable 00
IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
bcmgenet bcmgenet.0 eth0: link up, 1000 Mbps, full duplex
IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
{542}[ioctlVideo_SelectSource] (0) stream_source (0 -> 1) 
{542}[ioctlVideo_SelectSource] (0) stream_source (1 -> 0) 
{547}[video_videomodepreferred_read] mode(0) not found!!!
{547}[video_videomodepreferred_read] mode(0) not found!!!

I guess the next step will be to pull off the heatsinks and measure the voltage on the remaining regulators..
Do you know if removing the regulators would simply leave the tuners unpowered without causing any further damage? I may be able to find one compatible regulator lying around somewhere but I doubt I have four.

[MrQuade]

I'd advise that it would be a bad idea unless the repair is done completely and properly with new regulators that have a current rating that exceeds that of the stock ones, and that you devise a better heatsink connection using a compound that won't break down and damage the motherboard.

I'm not an expert in that area, other than to say you shouldn't half do the job of you want your T4 to last

[prl]

The actual direct cause of the problem isn't necessarily the regulators themselves. Breakdown products from the cement holding the heat sinks to the regulators can damage the circuit board and create a number of different issues (it rendered our T4 unbootable).

However, it's probably a good idea to replace the regulators anyway, if only to use pairs of regulators with the same package height to make it easier to bond the heat sinks cleanly onto the regulators.

And use a good quality thermal cement to bond the heat sinks to the regulators.

[michal]

Does anyone have an idea of what the cost to have someone do this might be?

[peteru]

Parts only, including delivery would be under $30. Equipment required to do the job without causing damage runs into many hundreds, if not thousands, of dollars. There is also a non-trivial amount of skill required to perform the job.

I'd expect that if you get the job done properly for under $150, you are doing very well.

[prl]

Both Grumpy_Geoff and I have had repairs of circuit board damage around the tuner regulators done by Warkus for less that $100, including postage.

The cost of repairs could depend on the extent of the damage.

The important thing to note is that the damage is progressive, and will continue while the degraded cement is in contact with the circuit board. Warkus has told me that it can progress to a stage where he can't repair the circuit board.

If this is suspected to be the problem (usually indicated by the cement holding the heatsinks to the regulators discolouring to brown or black), then get the repair done, however you choose to do it, as soon as possible.

[michal]

That sounds very reasonable.

Honestly though it doesn't LOOK anywhere near as bad. Apart from the dust I don't notice any discolourations and both regulators are measuring at 3.3v. That's not to say there isn't a problem with them, just that it's not apparent.

[prl]

You're right that it doesn't look too bad. On the other hand, it's the V1.1 boards that seem to be susceptible.

The circuit board damage doesn't necessarily directly affect the regulators themselves. In my case it appears to have shorted out the 5.5V switching regulator downstream from the tuner regulators (U32) and it went into shutdown, denying power to the tuner regulators, but also to enough of the rest of the board that the system wouldn't boot.

Grumpy_Geoff posted shots of his tuner regulators on Whirlpool. My regulators didn't look nearly as bad (the visible cement was more milk chocolate brown), but it still bricked the box.

This is what Warkus found when he took the heat sinks off (resolution reduced from the original):

PCB regulator damage.jpg (278.74 KiB) Viewed 19973 times

[MrQuade]

That's not to say there isn't a problem with them, just that it's not apparent.

Mine looked like yours with the heatsinks on, but similar to prl's post, once the heatsinks were off, Warkus said that the board damage was about as bad as he'd seen.

[prl]

This is the PCB after removing the regulators and cleaning the board. Patches where the solder resist was stripped off my the cement can be seen around the regulator locations.

PCB after cleaning.jpg (381.24 KiB) Viewed 19961 times

[stevebow]

Apart from the dust I don't notice any discolourations and both regulators are measuring at 3.3v. That's not to say there isn't a problem with them, just that it's not apparent.

Note that there are TWO regulators powering each pair of tuners, 3.3V (U45 A/B, U47 C/D) and 1.25V (U44 A/B, U46 C/D).

You can measure all 4 voltages at the inductors just above the regulators:

Tuners A/B:
3.3V - L56
1.25V - L57

Tuners C/D:
3.3V - L61
1.25V - L59

Measure each voltage at the end of the inductor closest to the tuners. If the voltage is not what is expected, measure at the end closest to the regulators to eliminate the inductor as the issue (very unlikely, but good to be sure).

[stevebow]

This is what Warkus found when he took the heat sinks off

prl, IIRC I believe you leave your T4 powered on 24/7? When I replaced my (3.3V) regulators and heatsinks, the amount of black discolouration was very minimal, and only between the regulators. But I do power down my T4 when not in use.

[prl]

This is what Warkus found when he took the heat sinks off

prl, IIRC I believe you leave your T4 powered on 24/7?

No, our T4 is powered down when not in use.

[Grumpy_Geoff]

This is what Warkus found when he took the heat sinks off

prl, IIRC I believe you leave your T4 powered on 24/7?

No, our T4 is powered down when not in use.

My T4 is in deep standby when not in use - but look at the photos (as linked by prl) to see what happened to it

[michal]

I won't get another chance to measure voltages till the weekend, but I thought I'd chime in to say mine is powered on (in standby) 24/7 so that it's ready to start recording if I add something via IceTV remotely.

[Paul_oz53]

I won't get another chance to measure voltages till the weekend, but I thought I'd chime in to say mine is powered on (in standby) 24/7 so that it's ready to start recording if I add something via IceTV remotely.

I'd be interested to know if yours is a Rev 1.1 or a Rev 1.2 board.

Unlike the photos above, my Rev 1.2 board shows no signs of similar damage nor any visible hint of the cement that appears to fail in the photos posted by prl. I wonder if Rev 1.2 was to address this problem?

Regardless, the relevant heatsinks definitely run at high temperatures and I am still considering replacing them while the regulators are still working in mine.

[Paul_oz53]

Parts only, including delivery would be under $30. Equipment required to do the job without causing damage runs into many hundreds, if not thousands, of dollars. There is also a non-trivial amount of skill required to perform the job.

I'd expect that if you get the job done properly for under $150, you are doing very well.

Indeed, I got the parts for less than $20 but after your earlier warning, I began watching YouTube videos of experts repairing failed SMD devices. Guys like Louis Rossman make it look easy if you have the gear. (Louis rants a lot against Apple's hostile attitude to repairing devices so be warned if you're an Apple fan. But he has a point - if you pay 5K for a Macbook and break it, you should be able to get it fixed for a reasonable price.)

Preheat ovens, computer controlled hot air rework stations, thermal masking tape, microscopes, solder paste and rework flux, ultrasonic bath, etc, etc. You could easily spend $10k kitting up for the job and no guarantee that you won't damage the board if you slip up even slightly! The regulators are relatively free of nearby components so at least that is less of a worry. My trusty Weller temp controlled iron just doesn't measure up.

[prl]

Parts only, including delivery would be under $30. Equipment required to do the job without causing damage runs into many hundreds, if not thousands, of dollars. There is also a non-trivial amount of skill required to perform the job.

I'd expect that if you get the job done properly for under $150, you are doing very well.

...
Preheat ovens, computer controlled hot air rework stations, thermal masking tape, microscopes, solder paste and rework flux, ultrasonic bath, etc, etc. You could easily spend $10k kitting up for the job and no guarantee that you won't damage the board if you slip up even slightly! The regulators are relatively free of nearby components so at least that is less of a worry. My trusty Weller temp controlled iron just doesn't measure up.

When Warkus repaired my T4, he replaced all four regulators (which might be feasible to do with a file-tipped soldering iron), but also two damaged SMD capacitors, which would be well beyond my confidence, skills levels and equipment to do.

[Grumpy_Geoff]

Unlike the photos above, my Rev 1.2 board shows no signs of similar damage nor any visible hint of the cement that appears to fail in the photos posted by prl. I wonder if Rev 1.2 was to address this problem?

If I understood Mark correctly, the Rev1.2 boards don't have the issue as they used good quality Japanese thermal paste (c.f. the crap Chinese stuff used in the Rev1.1 boards).

[prl]

Unlike the photos above, my Rev 1.2 board shows no signs of similar damage nor any visible hint of the cement that appears to fail in the photos posted by prl. I wonder if Rev 1.2 was to address this problem?

If I understood Mark correctly, the Rev1.2 boards don't have the issue as they used good quality Japanese thermal paste (c.f. the crap Chinese stuff used in the Rev1.1 boards).

My reading of it is that while the Rev1.1 boards appear to have the problem and the Rev1.2 boards don't, it doesn't have anything directly to do with the board Rev itself. Rather, it reflects the time when the thermal adhesive was changed. I think it's more to do with production runs, rather than the board version, but the board revision may reflect the relevant change in materials in the production runs. But it's possible that the change in the thermal adhesive happened in a later production run that used Rev1.1 boards.

The evidence seems to be that T4s with Rev1.1 boards seem susceptible to the problem, and that T4s with Rev1.2 boards don't seem to be affected, but it seems less certain to me that all T4s with Rev1.1 boards have the problematic adhesive (though it may be the case).

[Paul_oz53]

Thanks Grumpy_Geoff & prl,

You give me hope mine may last.

Still, these particular heatsinks do get quite hot if left on or in standby. When I get some space to breathe I'll probably jury rig a fan or replace the heatsinks since I have the parts. My biggest concern is how strong the heatsink adhesive is to break it off without ripping the traces.

[michal]

My biggest concern is how strong the heatsink adhesive is to break it off without ripping the traces.

^^^ This. I've got something sharp to try and cut it away with but it looks pretty solidly stuck down.

[michal]

Turns out my fears were well founded. Pulled the top off one of the regulators.

When I measured at L56 I got around 2.1v rather than 3.3v. Both regulators at the C/D tuners seem fine.

I don't dare turn it on now..

Does anyone know what the current ratings for the existing voltage regulators was?

[Paul_oz53]

Turns out my fears were well founded. Pulled the top off one of the regulators.

When I measured at L56 I got around 2.1v rather than 3.3v. Both regulators at the C/D tuners seem fine.

I don't dare turn it on now..

Does anyone know what the current ratings for the existing voltage regulators was?

Damn. I'll leave mine alone for now. The replacement I have is an LM1117 DT - 3.3.

[prl]

My understanding is that when Warkus replaces the regulators, he uses replacements that have the same package height for the pairs sharing the same heatsink. That makes for much better thermal contact between the pair of packages and the heatsink.

[prl]

Turns out my fears were well founded. Pulled the top off one of the regulators.

But from the discolouration under the heatsink, at least you now know that the job has to be done.

[peteru]

Yep, that regulator was cactus. First thing you need to do is remove all the contamination from the board. Isopropyl (at least 95% pure) is your best bet. Do not use water or any other solvents that could damage the board or components.

As far as the choice of the regulator to replace with, see the previous repair thread that has the discussion. In particular, pay attention to the advice to go to a larger package size.

Also see this thread.

[michal]

Would Shellite be suitable for cleaning?
I have Isopropyl alcohol but in the past I've always used Shellite for this sort of thing.

[peteru]

Definitely not. You want a non-residue cleaner, not an oil based solvent. It may work, but is not the right thing. Chances are that the crud that was there has already damaged things, so you really, really want to be careful and use the correct chemicals. IPA is the thing for cleaning PCBs and solder joints - NASA use it.

[michal]

Interesting. Thanks for the info.

I did some work experience at an electronics repair place when I was young and they swore by Shellite so I've always thought it was the thing to use.

Will switch to IPA from now on.

EDIT:
- Also what's the story with the 1.2v regulators?
- Are they unaffected by these problems?
- Should they also be changed?
- Has anyone done so and if so which regulators did they use? I can't really read the model number of the existing 1.2v regulator so I don't know what the current requirements are. Would this be suitable? https://au.rs-online.com/web/p/low-drop ... s/1677423/
- Scratch the above.. Minimum order of 20.. Could someone suggest an alternative available on RS?
- How about https://au.rs-online.com/web/p/low-drop ... s/8294373/ ??
- I had a look at fans for the 20mm x 20mm heatsinks I plan to mount.. but WHAT?!?! These prices are insane!

fans.PNG (69.14 KiB) Viewed 19735 times

[michal]

Things don't look particularly great for the other voltage regulators.

IMG_5541.jpg

(659.06 KiB) Not downloaded yet

I'm confused by the LM1085 as that's not a 1.2v regulator.

[MrQuade]

Those fans are 17,000 and 15,000rpm respectively.

The specs also say 25dB and 23dB, so I don't know for that works .....

Something that fast shouldn't be that quiet......

[Paul_oz53]

Things don't look particularly great for the other voltage regulators.
IMG_5541.jpg


I'm confused by the LM1085 as that's not a 1.2v regulator.

The LM1085 has an adjustable version with the output set by two resisors. I expect these are on the M/B. As such, a replacement must match.

There is no obvious need to replace the existing 1.2v regs if they are ok but matching the package height is critical if you do.

Check carefully and leave well enough alone if you can.

[peteru]

I'm confused by the LM1085 as that's not a 1.2v regulator.

It's an adjustable regulator. R531 and R532 nearby set the desired output voltage by acting as a voltage divider on the GND/ADJ pin.

[michal]

There is no obvious need to replace the existing 1.2v regs if they are ok but matching the package height is critical if you do.

RS has none with the required dimensions so I guess I'll just leave them alone. I've not heard of them dying for anyone else so hopefully all will be well.

[stevebow]

With my own experience replacing the 3.3V regulators and heatsinks: T4 - Tuners A/B have died

The original 3.3V regulators (LM1117DT-3.3, SOT-223 package) are very fragile, the cases can split quite easily despite care in cutting the thermal adhesive, but no problem really as they were being replaced anyway.

Use a single-sided blade, such as these from Bunnings: Uni-Pro Paint Scraper Blade - 10 Pack - these will let you cut in parallel to the heatsink without a bulky handle getting in the way. Due to the angle of the heatsink (because of the use of the SOT-223 3.3v regulator), start carefully cutting in on the 1.25V regulator end (LHS looking from the front). The adhesive is quite tough but perseverance pays off, take your time. As mentioned, despite care, the 3.3V case will possibly come apart as you gently lift the heatsink while cutting, but both 1.25V regulators seem to have survived the ordeal quite well.

[stevebow]

There is no obvious need to replace the existing 1.2v regs if they are ok but matching the package height is critical if you do.

RS has none with the required dimensions so I guess I'll just leave them alone. I've not heard of them dying for anyone else so hopefully all will be well.

No, as far as I am aware the 1.25V regulators have been fine, it's the 3.3V regulators that have been giving grief.

[michal]

I just got around to replacing the regulators and wanted to remove the board.. But that ribbon cable.. has it become FUSED with the connector or something? It IS supposed to be removable right? It's sitting in there so tight I can't get it out.

Any tips?

[michal]

Doesn't look so great underneath either.

IMG_5565.jpg

(473.37 KiB) Not downloaded yet

[prl]

I just got around to replacing the regulators and wanted to remove the board.. But that ribbon cable.. has it become FUSED with the connector or something? It IS supposed to be removable right? It's sitting in there so tight I can't get it out.

It is removable. I know because I've done it. I even managed to put it back, which is possibly more important

To remove it, I held the ribbon using the thumb and first finger of each hand (one hand each side of the cable), and firmly and evenly pulled it out of the socket on the main board.

To replace it, I reversed the procedure, being careful to hold the ribbon as close to the end being inserted as possible so that it didn't buckle, and taking care not to insert it at a skewed angle (which may damage the edge of the cable).

[michal]

Replaced the two regulators and fitted the heatsinks.

I now see all 4 tuners in the info, unfortunately I still get no signal.

Screen Shot 2019-05-21 at 6.07.44 pm.png (20.13 KiB) Viewed 19579 times

[michal]

Spoke too soon! A local rescan fixed it..

I guess I was thrown by all the previous rescans where there were no channels.. They must have replaced the previous config.

BIG thank you to you all for your help!

[michal]

Again, spoke too soon

Started off working but now every few seconds signal goes from 0% to 100% on all tuners.. Totally unwatchable..

No idea what the problem is.

This is all that I see in dmesg:

Code: Select all

IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
{536}[ioctlVideo_SelectSource] (0) stream_source (0 -> 1) 
{536}[ioctlVideo_SelectSource] (0) stream_source (1 -> 0) 
{543}[video_videomodepreferred_read] mode(0) not found!!!
{543}[video_videomodepreferred_read] mode(0) not found!!!
{594}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 
{543}[ioctlAudio_SelectSource] (0) stream_source (0 -> 0) 
{543}[ioctlVideo_SelectSource] (0) stream_source (0 -> 0) 
{606}[DNOQ44QAH109A_TuneTer] (1) PLLState = 1 
{594}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 
{606}[DNOQ44QAH109A_TuneTer] (1) PLLState = 1 
{594}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 
{606}[DNOQ44QAH109A_TuneTer] (1) PLLState = 1 
{594}[DNOQ44QAH109A_TuneTer] (0) PLLState = 1 
{606}[DNOQ44QAH109A_TuneTer] (1) PLLState = 1 

[michal]

I just don't have the stamina or time to keep hammering away at this tonight, but I think I measured 0v across L56 and L61..

But maybe I'm just too stressed by having it working for a short while only to have it fail again. It all makes a lot more sense now as sometimes the signal would falter quite frequently and I guess these regulators were probably the cause.

No idea what the next step is. I certainly can't afford to have it repaired anytime soon

[IanB]

New regulators not properly thermally bonded to heat sink and entering thermal shutdown mode ???