Hi together,

I already postet this in the german forum but didn´t receive any answer yet...

From one day to the other my LC2 stopped reacting to IR remote commands. It´s still possible to turn on/off and dim the light by touching the glass of the LC2 however it no longer reacts to remote commands. I have two different remotes and the same problem appears using both of them (I already changed batteries, but this didn´t help either - on the other hand, my Ouverture and my TV are still working). Meanwhile I found out that the LC2 isn´t damaged totally. When exposed to light, it starts reacting to IR commands again! The brighter the light the better the LC2 is working. Seems to be something wrong with the operating point of the IR receivers of the LC2.

Anybody ever experienced the same problem? Or knows a solution? Is there a service manual available for the LC2? 

Hi,

es gibt die IR Platine separat zu kaufen. Und es gibt sie mit einer neueren Revision, Plasmafernseher störten sie in der alten Version.

 Diese kleine Platine ist harmlos zu wechseln und kostet auch nicht viel... ich hatte vor einiger Zeit ein paar davon da wegen einer Blitzschlagreparatur. War so um die 20 Euro pro Einheit.

In München gibt's einige B&O Reparaturshops mit den Teilen ;)

Gruss

Martin

It sounds to me that you may have a Plasma TV near your LC2 or something similar

If you do have a Plasma monitor it will produce light and electrial noise which will cause no or poor remote control.

It is the light noise (370 kHz ) as well as the electrical noise from the plasma monitor. The noise level is approximately 20 dB stronger than the IR codes from the IR terminal. The 370 kHz IR light from the plasma monitor is disturbing the 455 kHz carrier wave for B&O IR codes.

I suggest you replace PCB 1 part no. 8000664 which is an updated version.

Keith Saunders:

I suggest you replace PCB 1 part no. 8000664 which is an updated version.

 Will it completely solve the problem? 

Hi together,

thanks for your replies. However there is no plasma TV in my room and I didn´t change anything else (as far as I´m aware). I detected that even the sensitivity of my Ouverture has reduced since some time. While I could point with my remote anywhere in the room to control the Ouverture, now I have  to point more directly to it in order to control it safely. My MX5500 TV however seems not to be affected.

I will try to get the supposed replacement part for the LC2 as I´m assuming that something got damaged in the LC2. I even took it to another room to exclude the effect of any interference with other stuff (like a plasma TV - that I don´t own).

I would welcome any hint on these problems though... 

Hi,

Maybe a stupid suggestion but, have you checked the batteries in your remote. When they are almost dead it is possible that an LC2 or Ouverture does not react while yor TV still reacts to your remote.

 Good luck! 

Hagen,

If you do not have a Plasma monitor, then it is something else creating interference at around the same frequency as the B&O remote.

Since the problem started what new electrical/electronic equipment has been newly installed within 20 metres ?

Sorry, my mistake. Good luck!

Hi Keith,

the last recent purchase was a DECT headset added to my Beocom 6000. I can not imagine that this is creating interference but I will make some investigations...

To bring the topic up again:

When taken to another room, the LC2 is reacting (almost) normally!

Created also a new topic as also my Beosound Ouverture seems to be affected... (see More IR problems)

Hi Keith, 

In the mean time I bought another LC2 and experienced the same problems as with my old one! I took both LC2´s to my office and - voilà - here they are working perfectly, even in total darkness. Something must be going on in my appartment...

I made some examinations with an IR receiver and an oscilloscope to be sure that there isn´t any infrared source disturbing the LC2. However I couldn´t detect anything unnormal.

Must have something to do with the power line or any other RF interference... 

Hagen,

Well, lets recap on the information to date:-

• The LC2 works perfectly in your office.
• You have purchased a second unit which fails in the same way as your original.
• You live in an apartment..

Well the problem must either be caused by:-

• RF interference, either from within your own apartment or from a nearby apartment
• Mains born interference such as the use of mains networking products.

So, given I believe you have already ordered an updated module for your LC2 and are just waiting for its arrival, we should look at the mains situation. The easiest way to eliminate the power as a possible cause is to connect the LC2 up to the supply in a room as far away from its normal position and determine if it works or fails. As all your rooms will be on the same mains supply, if the LC2 now works correctly then it will NOT be a mains born interference. If it still fails, then I would ask a person in a nearby apartment if you could try it again in their apartment.

Having said all this, and I do think it is important to go through the process, I still believe that you have an RF interference issue here and it may not be coming from within your apartment. One way to test this theory is to make a small Faraday Cage out of chicken wire (mesh) and connect it to ground and put it around the LC2, if the LC2 now works you know it is RF interference which is causing your problem.

What is a Faraday Cage 

A Faraday cage is a metallic enclosure that prevents the entry or escape of an electromagnetic field (EM field). An ideal Faraday cage consists of an unbroken, perfectly conducting shell. This ideal cannot be achieved in practice, but can be approached by using fine-mesh copper screening. For best performance, the cage should be directly connected to an earth ground.
Faraday cages are used in electronic labs where stray EM fields must be kept out. This is important in the testing of sensitive wireless receiving equipment. In addition, a Faraday cage can prevent the escape of the EM fields emitted by a cathode-ray-tube (CRT) computer monitor. Such fields can be intercepted and translated to allow hackers to remotely view on-screen data in real time without the need for wires, cables, or cameras. This practice, known as van Eck phreaking, can also be used by government officials to view the computer activities of known criminals and certain criminal suspects.

Hi Keith,

firstly I want to thank you very much for the time that you spend on this topic and for your efforts to solve it!

I "constructed" my own Faraday Cage and yes!, it made the LC2 working again - though not perfectly.

I also removed everything in the living room from the mains and even used a line filter but these things did not improve anything.
 

Hagen,

Well, I very much like your Faraday Cage, the fact the LC2 then worked means you problem is NOT mains interference based, but is Radio Frequency or Electromagnet emissions.

In today's world, RF Interference can come from some very surprising places.

A few years I helped someone with a problem with their AVANT which had Beolab 4000 for rear speakers. When the powerlink cable was put across the floor of the room to the speakers everything worked perfectly, however when the cable was mounted in the wall, the on/off relay in both speakers would oscillate producing a buzzing sound. The cause was a local radar station about 3 KM away and earthing the powerlink ground to mains earth sorted the problem.

So, why did I tell you this story because the cause of your problem may not be in your apartment, but could be from a nearby apartment or even beyond that. So, I think we need to ask the following questions:-

• Is your apartment on the ground floor ? and is its construction mainly of concrete ?
• Does anyone have a Plasma TV in an apartment near you ?
• Do you live near a mobile phone tramsmitting mast ?
• Have you tried the LC2 in a friends apartment near you ?

Keith,

thank you for your hints. My second LC2 does not benefit from my "Faraday Cage" what makes me a bit unsure...
Here are the answers to your questions:

• I live in the first floor (in Germany we count ground floor, then first floor and so on, so may be you have to read "second" floor) and it´s not built of concrete. It´s an old building and I think the ceilings are wooden and the walls are consisting of bricks.
  
• Plasma TV: I don´t know. But I assume that it would interfere only when in use and that is presumably not the case. The LC2s however are not working independently of the time of day.
• Who doesn´t...
  though there isn´t one directly visible around my home.
• Not yet but I will go and ask them the next time.

I took the second LC2 to different places in my appartment and found some places where it sporadically reacted to the remote control though I couldn´t recognize a clear scheme.

I think the next step should be to determine whether the radiated emissions are from within the house or from the environment. This will require some special measuring instruments and I will research where to borrow them or where to engage a technician.

As soon as there is more news I will let you know! 

I just want to share the latest results of my investigations.

I borrowed measurement equipment that allows the detection of:

a) magnetic and electric fields in the range of 5Hz to 100kHz

b) electromagnetic fields in the range of 800MHz to 2,5GHz (DECT, GSM, UMTS, Radar, Bluethooth, WLAN)

For the manufacturor homepage please click here.

I add some pictures to give you an impression about the devices.

However I didn´t detect any abnormal signals in the HF range. Neither in my appartment nor in my office. The highest signal is produced by the DECT base station of my BeoCom 6000, which is permanently emitting electromagnetic fields.

The antenna allows for locating quite exactly the position of the signal source and I could clearly determine the place of my neighbour´s DECT base station.

Subsuming I couldn´t detect any reason for my LC2s no longer working in my appartment, what is a bit frustrating.

The next step will be an analysis of the mains in my appartment.