B&O Beovision MX2000
 

Hi All,

I picked up a Beovision MX2000 its in decent condition externally it was just very dusty, but its cleaned up rather well. I only paid £49 and came with matching remote too.


The TV does have a couple of niggles though. The left side speaker isn't working, but using the external inputs on the rear and plugging in my Beovox CX50's both channels work fine.

I have actually swapped both the internal right and left speakers around and the left side still isn't working. Seems like an odd fault and I'd have thought the left input externally would be dead too if it was a problem with the amplification circuitry?

I think the 3.6 volt Nicad battery which stores the TV's settings and information also needs replacing. I'll need to locate that as I had a quick look inside and didn't see anything.


The main downside though is the smoked perspex panel which sits in front of the CRT has an ugly scratch almost in the middle of the display about an inch long. I Just wondered if anyone has or knows where to source a replacement piece of smoked perspex which will fit it.

I saw a few older forum posts online dating from 2007 and apparently someone sold replacements on eBay, but sadly I have not been able to find them now.


If anyone is in the North or East Yorkshire region I wouldn't mind getting it properly serviced and inspected actually. I think it would be worth it to get the best out of it.

Going to be my TV I have hooked up to my VHS, Betamax and PS2


Thanks all

Ryan

Re: B&O Beovision MX2000
 

Hi Ryan,

There are a couple of ways for the signal to go missing in the speakers.
Each round DIN speaker-sockets for external speakers has a built-in switch to disconnect the internal speakers once you connect external speakers.
When you unplug the external speakers the contacts are suppose to re-connect the internal speakers.
They may fail to do so because of being defective, corroded or simply need to be re-soldered in the printed circuit board.
There's a jack-socket for connecting a headphone to the TV as well, and this socket has built-in speaker disconnect switches like the ones in the DIN-sockets.
Obviously these contacts could be subject to the same kind of problems.
You may even be so fortunate as to have switches act up in both places.
Then there's the possibility of the simple wiring to the left speaker has gone faulty.

rgds,

/Torben

Re: B&O Beovision MX2000
 

Great little telly's these.
As Torben states,the audio output circuitry is quite complex,with various options for speaker and headphone connection,but the problem will be fixable.The socket assemblies tend to suffer where they connect to the main pcb,and of course,the switch section of the headphone socket can become tarnished with age.Try some headphones,to see if both channels work there?If so,it will narrow down the source of the problem
The memo batteries are available (eg via CPC etc) as NIMH types nowaday's.The original's tended to corrode and damage the pcb.It's down on the main pcb towards the left hand side,looking in from the back,and usually has a blue sleeve.
I have a spare contrast screen.It does have a couple of marks on the outside,but you may be able to polish these out.The contrast coating is on the inside.The screen measures approx. 48cm across and 35cm top to bottom.
The set is essentially a French Tomson chassis,remodelled by B&O,so should be familiar to anyone with experience of Ferguson etc tv's.
Let me know if you'd like the screen,and I'll work out the postage.
Nick

Re: B&O Beovision MX2000
 

As said, the MX2000 is a Thompson chassis modified by B&O to compliment its own family of audio visual equipment. It was also used by other manufacturers and some spares are still available.

The chassis, ICC3, is the subject of a number of posts on this and other sites and the schematic is available online. Speaking of which, the backup battery is shown as 2.4 volts which is available and can be found by reference to the schematic. Typically, the battery will be soldered onto the pcb and its demise will mean that the preset channel/volume/contrast etc will not be memorised.

I have the later ICC5 chassis and the picture geometry and quality is very good and given adjustments are still analogue in nature, a doddle to set up..

However, the I'm not convinced that the dark plastic anti glare screen is a bonus as it requires the CRT to be worked hard and, for me, the black level is very good without it.

Good luck with getting the internal speaker working. Logic suggests its a simple fault because you say using an external speaker works.

Chris

Re: B&O Beovision MX2000
 

Check around the back up battery. They rot and leak corrosive fluid everywhere causing circuit board corrosion. The tracks literally vanish!
I got that tip from another Forum member while repairing mine. It was in a mess but we managed to get it cleaned up and the tracks bridged OK. Back up batteries were always a pain. John.

Re: B&O Beovision MX2000
 

Isn't the battery on the control board on the back of the chassis in this model? Or are there two? I remember some ICC5 variants had 2 batteries, one for the Teletext memory but I don't think this applied to the ICC3.

Re: B&O Beovision MX2000
 

The Back-up NICAD is on the System-board PCB-08, see the attached.

I seem to remember it was a 2-cell NICAD type making it 2,4V

Rgds,

/Torben

Re: B&O Beovision MX2000
 

Hi Max thanks I have PM'd you about the screen.

I have just tried headphones, but only the right channel works on headphones just like the TV speaker. Using the external 2-pin Din speaker connectors on the rear my Beovox CX50's both work fine for left and right.

I was intending to use it with external speakers anyways, but it would be nice to get the internal ones working too.

Next thing is going to be the battery to look at. There is lots of options online on various parts suppliers all different shapes and sizes in regards to a 2.4 volt. I also searched eBay, but that wasn't much good as it just kept coming up with batteries for cordless drills and power tools and nothing much else.

Re: B&O Beovision MX2000
 

Thanks Torben, I will open it up tomorrow and remove the battery for now.

Is the battery easy to access and remove or do lots of other things have to be removed in order to get to it

Re: B&O Beovision MX2000
 

The module is freely accessibly and you should be able to replace the battery even w/o removing the module.
Unless that is, that corrosive acid has been released by the defective battery.
In that case you may have to do repairs to the PCB and replace any corroded components.

rgds,

/Torben

Re: B&O Beovision MX2000
 

Thanks Torben

The battery came out easy enough. A little bit of bubbling of the underside of the PCB but I have seen a lot worse in old Apple Macintosh Computers.

What does this board control? Assume its nothing to do with the speakers or amplification? Was just just pondering if the slight corrosion on this board would lead to the left front speaker not working. I’d guess it was for the settings and memorisation of the pre-sets?

It also looks like it has had a repair at some point in its life. A couple of resistors seem like they were added in by hand.

Photos attached

Re: B&O Beovision MX2000
 

I'd try an extension speaker, headphones and so on to see where you're losing the signal. I agree with Torben that the fault will be close to the output, and often inserting and removing a plug a few times will wake it up.

Re: B&O Beovision MX2000
 

Thanks again all for the help.

Going to order a new battery this one seems to be the closet match on CPC.

The mAh is lower on the new one, assume it will still be okay?

The original battery inside was rated at 2.4 volt, 170 mAh, whereas the replacement is 2.4 volt, but only 80mAh.

Cheers

Ryan

Re: B&O Beovision MX2000
 

You will have to double the value of the charging resistor.

Re: B&O Beovision MX2000
 

Ryan, Thank goodness for Maarten. Should you be unhappy in making the change, help is at hand.

The correct type from, for example Amazon, is £4.22 inc delivery or from E44 Electronique @ 4Euros. Just search for the part description including the 170mA specification.

Chris

Re: B&O Beovision MX2000
 

Thanks,

I found it all okay and ordered.

Thanks again

Ryan

Re: B&O Beovision MX2000
 

is there a balance control in the menu, and if so, is it being wound to one side due to the battery failure?
I was thinking about the old philips chassis that used NiCd batteries which when dead could sometimes come on with the volume set to max or the colour turned right down or other annoying problem.

Re: B&O Beovision MX2000
 

My parents old CTX used to have a loud default volume and colour level if it was swtiched off when the memory battery went flat.

Re: B&O Beovision MX2000
 

Thanks for the information. The TV being from 1985 doesn’t have any on screen menus or settings. It has a flip up door on the top with physical sliders and buttons. For balance, treble, bass etc and then standard power and fine tune buttons too.

Re: B&O Beovision MX2000
 

Just want to say thanks to member Max Ripple For providing me with a replacement contrast screen.

I recovered the speaker grille and fitted the screen earlier. Much happier, it’s pretty much spot on now.

Thanks again.