TM 6900 lnb power problem?

[harhosk]

My TM-6900 HD Super seems to have a problem with its LNB power supply. It worked straight out of the box, but not for long. After a few seconds (or minutes, if I am lucky) the picture vanishes, and a pop-up says that there is no signal. In the satellite setup menu, the signal strength and quality bars show as red. If I switch off LNB power, then switch it back on again, the bars show as blue and yellow (strength 95% quality 75%) and normal function returns. But the signal drops after a short time, and the strength and quality bars return to red.
I have a Titanium quad LNB (TQSG), which is connected to 3 TM 1000-D Supers, as well as the 6900. All the other receivers work perfectly. If one of the other receivers is switched on, the 6900 works perfectly. Presumably LNB power is supplied by the other receiver.
I have installed the software update of 10/10/08 (version 6.60), and done a factory reset, and switched it off at the back, etc, etc.
I have checked all connections, and tried swapping cables & receivers, with no improvement.
Is the TM-6900 Super faulty? Or is there a problem with my setup?
I have contacted Technomate support. None of their suggestions worked. Any ideas?

 

[Robbo]

It may be an overheating problem, have a look half way down this thread:-

http://www.satellites.co.uk/satelli...4-new-motorised-dish-assembly.html#post778353

 

[thecaretaker]

Hi, it was me with the overheating problem.

Try opening the front flap and putting a desk fan in front of your receiver. If after a a couple of minutes the signal returns, remove the fan and see how long it takes to fail again. If you do this a few times and it works every time, then I'd say it was a similar heat problem.

I wouldn't recommend doing what I did (unless you really want to), if you don't mind being without the box, get in contact with Technomate and get the box exchanged. Or maybe your supplier would be prepared to do that anyway.

However, the fan does give the added safety net of making any cams (I have a Diablo) run cold as ice which can't be a bad thing.

I suppose if a number of users have this issue, then Technomate really ought to be made aware. It does seem a recent issue and maybe due to a different/cheaper component or slightly different component spec/build. Mine wasn't the new super, but it was purchased a matter of weeks before the super was officially released.

EDIT: Oh, I will add I only had the issue on a few channels. Some channels were fine, I only lost signal on a few odd transponders on each satellite. It didn't relate to signal strength or quality, even Sky News at 28.5E which I get at 89%/86% suffered this problem, so it is not related to a weak signals. Some very weak signals at 30% were perfectly watchable. It really didn't make sense. Melodyzen HD at 9E I found to be the most troublesome.

Hope this has been some help to you.

 

[harhosk]

thanks for that, but I don't think it can be overheating. there's plenty of space around it, and it can cut out seconds after switching on. If it overheats that quickly, it's defective, and will have to go back.
The weird thing is, the signal & picture return as soon as I switch another receiver on, connected to the same lnb. I suspect some kind of voltage problem, as it sometimes runs for a while on an H tp, but goes off when it encounters a V tp.

 

[thecaretaker]

thanks for that, but I don't think it can be overheating. there's plenty of space around it, and it can cut out seconds after switching on. If it overheats that quickly, it's defective, and will have to go back.
The weird thing is, the signal & picture return as soon as I switch another receiver on, connected to the same lnb. I suspect some kind of voltage problem, as it sometimes runs for a while on an H tp, but goes off when it encounters a V tp.

As you suggest, could the lnb not be supplied power from one of the other recievers when you turn them on?

Does the problem still occur when the Technomate isn't using loop through?

From what you say, if it definately occurs with V pol and not H, then there is something else causing the problem like the switching circuit if assuming the lnb is working with other recivers OK.

Give my heat test a try, you never know. It sometimes only took mine 30 seconds or so before I'd loose the signal. Before it totally failed, I'd get a lot of popping and cracking sounds where the box was trying hard to produce a picture.

 

[satelliteman]

Get it repaired properly

 

[harhosk]

Thanks thecaretaker. Our posts crossed, but I have now tried your cooling trick, perching a small computer fan on the drop-down flap. Unfortunately it didn't work: the signal went just as quickly as before. I think I will try and return it to Technomate for testing or replacement.

 

[hill_piper]

Hello,
and sorry for this very late answer but same problem happened to me : once plugged, the signals from lnb were all good before fading out slowly (less than a minute). Disconnect, reconnect the F connector from lnb and same thing starts again : good signal drops down to 0 rapidly. I've just spend whole saturday getting very frustrated. I don't know if you've find out what was wrong with your lnb, as for myself, I just happened to disconnect the F connector at the back of the receiver and once properly reconnected, the signals were all stable after that ! ! A strike of luck more than anything else

I don't have a clue how a loose connection can lead to such weird symptoms but I may as well let others know. It might save someone a frustrating afternoon ! ! !

Regards

 

[harhosk]

Thanks for your contribution. I have (at last) been able to test my receiver on a friend's professionally installed Sky minidish (as recommended by various people). It showed exactly the same fault as it did on my setup. As a result the supplier has taken it back for testing and possible replacement.
I will report back when I know the result.

(by the way, I went through every variety of uplugging/replugging, cable tightening/swapping, etc, without solving the problem)

harhosk

 

[hill_piper]

Unfortunately, I'm not over with my setup yet !
Problem with the signal fading out is over so far but I still can't operate my new motor properly.
Convinced my lnb was the weakest link, (it's an old one for a start and everything gets wrong once it is connected... whereas my motor is brand new ! ) I was browsing on different internet sites to get a new one ... but now after I've red your answer, I'm not sure anymore who's the culprit ! I may as well test my axil box first. Could be that the power supply to motor/lnb is not up to the mark anymore

I've been up till 4 this morning with my multimeter testing the various combination (I know, how crazy is that ?) but I wanted to pinpoint what was wrong. Here are the figures :

lnb / motor dish power supply is OK (15/19 V depending on the transponder)
Power consumption (BTW, the lnb output of my axil is expected to supply 400mA, which is far more than what I need) :


motor alone not moving : 30 mA
motor + lnb not moving : 130 mA (channel reception is as good as it's always been before I changed the motor)
motor alone moving (without any problem !) : 180 mA
motor + lnb moving (with lots of problem !) : 250/270 mA
It usually works for 3-4 seconds the first time I press west or east on the remote (moreover, the motor sounds really slow), 1-2 seconds the second time I press the remote (the motor is in agony now) and the third time, power consumption goes from 250 to 0 mA almost instantly!! (not even 30 or 130 but 0.08 mA !). And that's it. My setup is brain dead and won't respond to any stimuli. To get it back to life, I have to disconnect the dish motor from any power supply for it to get out of this "error" mode and then I connect it back to the box.
Same story when I operate the dish directly from the motor (pressing the west/east button)



If anybody has any suggestion (specifically : how do I know that the lnb output is up to the mark ??), don't hesitate because I'm getting tired )(-red...in every meaning of the word U-zzz
I'll keep the forum posted.

Regards

 

[hotkich]

hi I have a tm-6900 super box which I have not setup yet, can you please tell me what I need I have disque 1 motorised system which I have been using with my tm-7755 2va 2ci box, no problems no hd,. thankyou for your intrest best whishes all hotkich

 

[harhosk]

Having started this thread, I think I am going to bring it to a close.

After testing my receiver on a friend’s dish, I found that it had exactly the same fault as it did on mine. The people I bought it from (Satellite Superstore) then agreed to take it back for testing. Unfortunately they found nothing wrong with it. They think there is something wrong with my setup, but apart from a vague idea about a faulty lnb, can’t suggest anything.

I now have it back, and it is malfunctioning exactly as before.
I have tried swapping cables, updating software, etc, as before, with no improvement.

It does work, proving I leave another receiver switched on and connected to the quad lnb. This is a minor inconvenience, but I think I can live with it.

So, unless some genius out there can come up with an answer, I think I am going to draw a line under this problem.

Thanks to all who have replied.

 

[thecaretaker]

Well, I had an electrician look at my original TM (after buying a super to replace it). It seems it is due to a faulty power supply capacitor. He said with power supply capacitors, when you turn them on from cold they out put their required power but as they warm up (which can be very quickly m8) the power output from them does drop slightly. Normally it isn't enough to cause any problem. But if the company sources cheap or unknown origin capacitors then for equipment as sensitive as a satellite reciever can run into problems.

My SkyHD box blew up after just a year thanks to the cheap crappy capacitors that Thompson use and it is such a big known problem that companies now offer quality DIY replacement power supply kits as Sky will only replace like for like or a refurbished box.

My electician friend could replace the faulty capacitor, but I've told him not to as I now use the Super model.

I'm only suprised that Technomate couldn't find the fault for you or maybe they supplied another box with the same fault.

Guess it is down to the quality of componants that technomate purchase and might say a lot about the quality of Technomate recievers.

So, if this is the same issue as you had, we were both right. :-)

Cooling my box did cure it for a while but I then found that no amount of cooling would keep a picture on some channels for more than a couple of minutes. The capacitor was just failing and dieing a death.

 

[harhosk]

Funny you should mentioned crappy capacitors. My Pinnacle Soundbride internet radio recently died when the power supply failed. Luckily I found someone to reair it. He says that cheap capacitors cause regular failures in that product, ususally just after they are out of warranty.

As for the TM6900, I will just have to live with the problem.