BM 8000 display module with lens filter removed.

BM 8000 volume display segment, half completed. The replacement surface mount LEDs are soldered on the left digit segement vs the original LED segment on the right digit.

The surface mount LEDs have a plastic lens over the semiconductor. Unless you are able to solder the LEDs in the exact position, the plastic molded cap which forms the digits will not fit over the surface mount LEDs. What I did was use an razor blade and shaved off the edges of each segment of the plastic mold to make room for the large LEDs. 

BM 8000 completed frequency display module.

BM 8000 Display Fully Restored.

A few things to note here. The top row of the display has been completely rebuilt.

The "Balance" segment did not have any bad segments and so I elected not to swap out the LEDs.

The true color of the original display is the ">" arrow segment of the Balance display.

The digit of the Balance display is much dimmer than it should be even though the LEDs are the original factory ones. The is because the digit segments are are strobed. This digit shares the same current dropping resistor as one of the digits on the top row. To make the replacement LEDs match the original intensity of the BM 8000 displays I had to change all the current dropping LEDs by a factor of 10X. I used 820 R resistors. Since the Balance digit is unmodified, the intesity there is now lower. I never use the Balance on the BM 8000 and so for practical purposes that display never comes on.

However this picture illustrates the relative intensities and color of the original vs new LEDs.

Excellent work! Very nicely done.

Hi Auric,

Agreed, well done!

I think you have solved an ongoing headache for many owners of these systems, who were not able to resolve the issue of the digital displays failing.... As an owner of a 6000 I'm feeling better now knowing that there is a solution that probably most techically savvy people can execute themselves and or get a repair centre to do for them...

Again, well done!

Laurence.

Derek,

Thanks for sharing the pictures and your painstaking repair process.  I am waiting for a few more parts then I will start my rebuild.  I probably have to do the same displays you did.  My volume and balance are completely dead.  The frequency has a few segments out.  I will post pictures of the completed process.

Gerhard

Superb work!

I'm very impressed with the results.

Chris.

Hi Gerhard:

Since it is unlikely that ALL segements would go bad on your volume display, I would suggest that you look at the decoder IC to make sure that it is not dead. Or simply measure the voltage across each segement to check for power.

Let me know how you make out!

Oh I also used a higher value resistor on the decimal segement of the volume display. Since this LED is on all the time (as power indicator). I didn't want to it to burn out prematurely so I made it slightly dimmer than the rest.

Derek