ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hello,
My BeoMaster 7000 is struggling to receive a source command from my Beo4/BeoLink 1000 like RADIO, CD, A.TAPE or PHONO. If I come closer like 1m away it works.
However, once the system is started it can receive all other commands perfectly fine like volume changes tracks, source change etc. It is only struggling when in stand by to receive a turn on command by chosing a source.
What can be wrong? Any ideas?
Thanks, BeoMedia
Typically this means the Beomaster is starting to be ripe for a recap. The lower supply voltages are unstable and disturb either IR reception or operation of the CPU.
But, if you have the FM aerial connected to a wall outlet, try disconnecting it and test again.
--mika
Hi Mika,
Thank you for your quick and competent reply!My plan was to replace the backup battery in the BeoMaster 7000 (to avoid acid leakage) so could have a go at this at the same time.
PS: The BeoMaster is not connected to FM aerial wall outlet, only a simple T-Wire antenna lying onto the floor.
I have the service manual for the BM7000.
Shall I be looking at the diagram "11-3: Diagram C Microcomputer, IR transceiver, Display" ?
Still, I am not a pro here in anyway so...what are the exact components I should be replacing please?
I have now found your previous thread about your BM6500.
Am I correct in thinking that what you suggest I replace is what you mention:
tournedos replied on Sun, Mar 4 2012 6:10 PM on this thread: https://archivedforum2.beoworld.org/forums/t/255.aspx ?
I will need to order these parts before I open it up as I have none of this at home If possible could you list what I need if ok to ask you?
BeoMedia
BeoMedia: Hi Mika, Thank you for your quick and competent reply!My plan was to replace the backup battery in the BeoMaster 7000 (to avoid acid leakage) so could have a go at this at the same time. PS: The BeoMaster is not connected to FM aerial wall outlet, only a simple T-Wire antenna lying onto the floor. I have the service manual for the BM7000. Shall I be looking at the diagram "11-3: Diagram C Microcomputer, IR transceiver, Display" ? Still, I am not a pro here in anyway so...what are the exact components I should be replacing please? I have now found your previous thread about your BM6500. Am I correct in thinking that what you suggest I replace is what you mention: tournedos replied on Sun, Mar 4 2012 6:10 PM on this thread: https://archivedforum2.beoworld.org/forums/t/255.aspx ? I will need to order these parts before I open it up as I have none of this at home If possible could you list what I need if ok to ask you? Many thanks!!! BeoMedia
Be very careful in just starting to change all capacitors at once. The traces on the PCB's are very fragile, and requires low as low heat as possible, but also heat enough to unsolder quickly. It is very easy to lift the traces, or create bad solders on these old units.
I would try to fix the problem first, and first after the problem is solved, begin to change other components. It is easy to introduce new errors before the old ones are fixed.
Even a T-Wire antenna can cause the IR to not work, so try to remove that also.
An oscilloscope is the only way going forward, in finding out where the noise that is disturbing the IR is coming from.
/Jacob
Hi Jacob, I removed the T-Wire antenna but the problem remains. Do you think that it can simply be old dust on the IR receiver and behind the glass of the front of the BeoMaster I could clean off? If so would that explain that it receives perfectly once the BeoMaster 7000 is turned on? It reacts to all commands perfectly.
Happy to learn about an oscilloscope. Do you think this one would suffice for this project or does it have insufficient specifications and features? https://www.ebay.co.uk/itm/2-4-DIY-Measuring-Instruments-Oscilloscope-TFT-LCD-Digital-DSO138-SMD-Set/173279150520?hash=item28583e01b8:m:mRql7fAGarGR31rbd6gUjRg
Kind regards BeoMedia
Alternatively this one:
eBay Oscilloscope alternative 2
?Best regards, BeoMedia
Hi Jacob,
I have read up a little on oscilloscopes as I understand it I would also need a function generator to allow me to measure a capacitor.
I guess the challenge is measuring the capacitors in-circuit but don’t you think I should be able to identify a bad capacitor with more than 10% in deviation of normal value even with a multimeter or an ESR meter?
Advice is much appreciated. Thanks BeoMedia