Tm 6900 hd super combo Power supply problems?

[zudrick]

My tm 6900 hd super combo powers up ok and after a few mins the screen flickers and the whole set freezes can not do anything with it other than switch it off wait then switch back on but it will do it again in a few mins. I have noticed that if i've got my usb drive pluged in it seems to do it sooner. Any help on this matter would be most helpful.
:bowing-036:

[holmroad]

Suggest you take alook at my thread here mate:-
https://www.satpimps.co.uk/showthread.php?150508-USB-on-TM6900HD-Super&highlight=capacitors

I experienced much of what you are - alongside USB's ceasing functioning - and changing the capacitors etc as described in this thread have so far corrected my problems!
Good luck mate!:respect-050:

[whompus]

There are problems with capacitors failing on the power supplies, https://www.satpimps.co.uk/showthread.php?150508-USB-on-TM6900HD-Super&highlight=USB+fault this thread will give you more info.

[betas]

Try resetting box turn power off hold down menu switch on a while holding menu appears on screen choose reset and see if it helps

[zudrick]

Got a new Power supply from Technomate but am still having the same problem, tried resetting the box by turning power off hold down menu switch on a while holding menu appears on screen choose reset did not help, have loaded firmware (original 7.42 and Phamtompatch 7.45p) via serial cable still same also it seems whenever i use the 8281 it locks up i have installed a fan but still same problem am thinking it could be the LM317T Voltage Regulators thats at fault?

[holmroad]

Got a new Power supply from Technomate but am still having the same problem, tried resetting the box by turning power off hold down menu switch on a while holding menu appears on screen choose reset did not help, have loaded firmware (original 7.42 and Phamtompatch 7.45p) via serial cable still same also it seems whenever i use the 8281 it locks up i have installed a fan but still same problem am thinking it could be the LM317T Voltage Regulators thats at fault?

And have you tried loading patch after first factory resetting as described previously mate:-
Backup channel list
Factory reset
Load 742 orig firmware
Factory rest
Load patch 745P
Load Add-on
Factory reset
Reload channel list
Load latest softcam

Off you go!

Did you do all this to remove any built up extraneous crap first mate?

Please advise!:respect-013:

[zudrick]

Will give it a go and report back my results

[zudrick]

Well have tried what you said

Backup channel list
Factory reset
Load 742 orig firmware
Factory rest
Load patch 745P
Load Add-on
Factory reset
Reload channel list
Load latest softcam

It did work for about half an hour watching the free FTA but as soon as i switched to a scrambled channels it did the same as before the only thing i think it might be is the LM317T Voltage Regulators on the main motherboard it's near the LNB tuners. All the electrolytic capacitors on the main board are ok or should i say look ok?

[zudrick]

Well everybody here is an update to the problem i've still got. Running Phamtom patch 7.46p. If i only use 1 card sharing server and don't have a usb drive plugged in it works ok, this means i carn't record anything or watch anything i've recorded which is a bit of a bitch to say the least. Will keep you informed on my progress!

[stroker]

I have been having USB trouble on my TM6900HD Super recently but I have managed to overcome the problem by fitting a 0.1uF capacitor between the middle(output) pin of U18 and 0V(front end of R13).

U18 is a variable voltage regulator(UZ1085LADJ), producing 5V, mounted flat on it's back near the front panel display connector which is near the front right corner of the main board. I am thinking that there is some sort of instability or oscillation going on in this part of the circuit.

I did this before noticing the posts about the power supply capacitor problems. I have not changed the power supply capacitors and do not intend to unless the problem returns. I found that a 0.01uF capacitor also did the trick but thought the higher value would be better.

If you still haven't solved your problem perhaps you can try this fix. I hope this helps.

[Hamrag1]

Faulty Power supply Capacitors cause a voltage ripple on the supply rail to the 5 volt regulator et al.
placing a small capacitor across the 5 v regulator, could indeed, for a time reduce the ripple at that point, but the
supply caps can only get worse, and eventually blow.