[Die_Bogener]

7-segment and Led’s for the source are done with the same chip… and the relais.

[Die_Bogener]

There is a LED driver chip MM5450 on the display board. If there is a problem with overload of a segment… the chip has internal led driver resistors… it will have problems to activate the defekt segment causing a power failure of the display/cpu… that’s the flicker.

Try the amp without speakers to activate from 0 to 64 to check all these segments. Usually there will be a “8” problem… and a problem with the source led.

It can be the chip or the power supply itself.

Replacing the chip is very skilled work and the chip is hard to get.

Usually some caps in the power supply are the cause…

[Die_Bogener]

It is the internal resistor of these blue Philips/BC caps. They are NOT LOW ESR…

… and the player hates LOW ESR for C2103.

Replace all and everything whatever you want, but C2103 must be a blue Philips.

And check for cracks on the connectors.

[Die_Bogener]

Critical capacitors? On a VX5000?

That’s easy. 100%

Around 200…

Which one on this picture would you like not to replace? They are all dead.

Repairing a VX5000 means 100% replacement of all caps. Not even some percent. It really means 100,00%. Or dont start …

All caps in the VX are leaking. This board is complete dead and cannot be repaired. The acid has done it’s job. The copper is gone.

[Die_Bogener]

Original function of the signal board of a VX7000… repaired, restored, working, 100% function like it was 1989…

 

Modified board, repaired, 100% functional with satellite unit using the auxiliary port … and 50% less power consumption.

 

Original upper VX7000 board with useless analog TV tuner unit…

Modified upper VX7000 without analog tuner, no multilingual analog tuner, using satellite digital unit and can record it.

 

[Die_Bogener]

Is it necessary to have a VX5000? Can you use the functions of the VX5000?

The VX5000 is very, very special with it’s digital functions depending on the used TV.

This VX will not show it’s capabilities on a MX TV younger than a MX5500… it was made für the MX5000 and works perfect with it.

But connected to an MX8000 or any other flatpanel, the VX will not show any digital function at all. No multi view channels, no slow motion, no multi tuning … just standard playback and even some trouble with recording a tv program…

The VX5000 has so much trouble with its power supply, it becomes so hot inside, that it’s lifetime was limited to only 200-300h, maybe 1000h … when it was new.

The VX5500 has no digital functions and becomes not so hot, since there is no digital memory unit inside. It save a lot of power and has much better compatibility to later TV sets.

But: it is possible to modify the VX5000 to actual power functions. I’ve done it fpr some friends. It will use only 50% of it’s former power consumption, modified so far, that it has no tuner unit any more and works together with a satellite unit as an integrated system. Watching satellite using the VX5000 as an input port, of course inclusive recording satellite digital tv.

It’s also possible with VX5000 and VX7000… and the boards need 30% less components than before.

[Die_Bogener]

The computerboard fuse will blow, when the voltage is raising over 5,5V… there is a safety zener 5,6V diode on the cpu.

If the diode or the power regulator is dead, it will blow the fuse.

[Die_Bogener]

Around 10W is ok.

[Die_Bogener]

The counter is inside of the drive wheels… an optical sensor.

And it will not run without it.

But in the VX setup you can select “Counter” and “Title Counter”… 😉

And the “title Counter” will only start counting with a completed 100% rewind of the tape. It will not cound in the middle of tapes, just from the start.

 

[Die_Bogener]

I would never turn anything around in B&O equipment… only when i exactly know what i’m doing.

Clean the drive, the axles, motor with alcohol… it’s 40 years old hard grease.

First clean it, then oil it. Remove the old stuff 100%…

Old grease and fresh oil: after 3 month you have a superglue. Nothing will move any more.

[Die_Bogener]

If D10 was damaged, replace everything what was/is in this line. LEDs, resistors, coils, TR10 and everything triggering TR10.

Something must have caused this overload… probably the already mentioned C19 2,2uF… a dead c19 will destroy all and everthing around Tr10.

And the fuse with 0,5A for 40V is much to late, when this job of destruction is done.

Check also IC6 CD4001 on the cpu. If the 455khz generator fails, it will also trigger TR10. IC6 of th cpu generates the IR signal. TEST IT!

[Die_Bogener]

B&O used pretty good stuff for the cabinets and for the loudspeakers. The speakers were usually very, very good sounding material… besides the surrounds. But they can be fixed.

The electronics was almost every time standard. B&O always used the standard aplication of the chip, used by Philips or intel or whatsoever, 100% according to the chip manufacturer.

This had a high amount of reliability. Longliving material, but only standard in the soundquality of the electronics.

But this has also good effects. Longliving, good repair possibilities, good supply of spare parts and … it can be upgraded very easy with better material.

Compare a LM833 to a BurrBrown UA2134… 0,00001% distortions and 50db better noise… that’s not a world, that are dimensions of light years…

Test a good B&O tweeter with an average bipolar electrolyth cap. Just average, just like all others… nothing really special…

Test the same tweeter with a polystyrene MKS-4 100V Foil from Wima. Really Good!

Test the same with a 100V Audyn 5% selected tin or silver plated cap. Woooooowwwww, GREAT!!! Test the effect with “Hotel California…” you will not think, this is the same music. You do not need any bass or loudness or any sound control, nothing but 100% original sound to hear a new world.

But: 50 Cent versus 15 Euro MKS… worth every Cent. Audyn is expensive material. One Penta is around 200€ material, just material, no work…

[Die_Bogener]

Caps in the sound path are usually small types. 1uF-10uf are used.

Good material for the sound path are WIMA MKS-2 types…

They are available in RM5 size, can substitute usually every electrolyth standard cap.

Available in 5%, 10% and 20% quality, some selected in non magnetic and 2% …

Usually in RED, they are a good replacement. Non magnetic and 2% are great… but you need a lot of material of 5% and a very good Cap tool to measure it. The magnetic types can be used for something elso in the power supply…

Low ESR in the sound path? Very bad idea…

[Die_Bogener]

Yes, that’s right, i use my own picture hoster.

Since it makes no sense for me to upload all and everything to the website, i use this hoster. The space is not enough.

I had uploaded all old stuff on the pre-pre-pre B&O Website… and all of it is gone.

[Die_Bogener]

A BM5500/6500/7000 in standby, no amplifier running, no sound, no display, just the red dot: 20-25 Degrees Celsius… some degrees, maybe 5 degrees more than room temperature.

Anything else more means problems with transformer or voltage regulation…

 

[Die_Bogener]

Hallo,

dass der CD Player als solches läuft und funktioniert, ist die gute Nachricht. Denn das kommt eher mal seltener vor.

Die Platine hat eine eigene Stromversorgung für ihren analogen Sound. Sie generiert alles selbst. Prüfe, ob die beiden 8-poligen LM833 Operationsverstärker weiter symmetrisch versorgt werden… ich hab da was mit 2x16V in Erinnerung. Wenn da ein Weg ausfällt, ist der Ton weg…

[Die_Bogener]

When the cylinder head does not start, check the 12V line. It is quite normal, that there are caps making a short… and blow the safety resistor.

I have never seen a VX without cap problems. This would be the golden unicorn, 1 of a million… and i still have a dozen VX5000/5500/7000 still in use and have still around 50 in storage (had 340…), each year rebuilding some of them for very close friends.

If your VX is so good without cap problems, it was never turned on. But this will change very fast.

I have had some in brand new storage, never used, still in its transport box for over 20 years. None was leaking… 2 hours later after playing a tape it failed.

 

[Die_Bogener]

It is not normal.

There are 2 potentiometer on the amplifier section, adjusting the “no-load-current”.

Replace the pots (100 Ohms?) and look for this adjustment. 11mV across TP200-201 and TP400-401.

[Die_Bogener]

The capstan has something like a tachometer funktion. Pushed by loading a tape will initiate a reaction of the motor, a wake up funktion.

There is a 4.th cap on the motor, hmmm… 3,3uf… that is the tacho. replace it.

 

[Die_Bogener]

The VX5000 will never activate the cylinder head in a bright room and missing the loading unit. The VX hates bright light on the tape deck. Bright light=broken Tape

There is a switch under the loading gear. And 3 IR LED detecting a loaded tape. 2 receiver and 1 sender in the middle.

Without a tape it will NEVER start. The VX will also detect a missing or defect tape when the wheels are stopped and not turning. He will detect a stopping tape problem.

Only unloading will work with the button.

Loading works only, if the IR LED right in the middle ist manipulated with black tape. Loading, not running.

Without a real tape you cant test the VX. I use defect tapes which were glued or cut or mechanical damaged…

 

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