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,I recently got my hands on a Beomaster 6000 type 2251 which unfortunately don't work.As soon as the machine is powered, three dots and one arrow lights up, nothing more.I can not turn it on (or off), the buttons do nothing.The only life i can get is the volume sliding potentiometer under the aluminium lid, it does make the volume motor to turn (although the belt is slipping but that is another problem).+6,5V and +15V from board 16 is ok.+32V is not there because relay RL1 never activates.I have measured pin 39 on IC4 (reset) and it is +5V, as well as pin 40 (+Vp).I have tried manual reset (short TR5 base), it does nothing.Pot R89 seems to be ok.I don't have an oscilloscope at home to use, i could probably borrow one from work if i need to.My next thing would be to resolder the CPU-board, i have searched the forums and see that this is a commonly suggested thing to do.Has anyone seen this error before?Any suggestion on how to continue?
/ Joakim
Check the CPU reset circuit.There is a trimmer in this circuit and it can sometimes act up.Still no luck ? Rreplace the CPU.
Martin
Hello,Here's an update on my issue, and maybe for future reference if someone else is have the same problems.I managed to find a cheep donor machine, it was in poor condition and had an unpleasant odor.. BUT it did start.I replaced the CPU in my original machine (as i couldn't find anything else wrong with it)... and, lo and behold!It did start up now!But all was not good, the numerical display only showed gibberish in radio mode.The clock was fine so i knew all segments in the display was good.
I then replaced IC8 (the "prescaler") as i have read on this forum that it's a common fault, although all messages i have seen about this is that the FM-scale is stuck on 74,8Mhz.Strike again, after replacing IC8 i now have a working FM-scale, i can tune it from 87-108MHz.I even found an unused belt (to a tape deck) in my drawers that fit on to the volume motor dial drive so the thing actually works.
Happy as a clam i connect a couple of speakers to try it out, but no luck.I get no sound what so ever, no noise, so scratching, nothing (no i did not forget about the Speaker 1/2 switches).I tried both FM-radio and Tape2, not a sound.
I can set the "No-Load Current" on both channels to 22mV without issues, and the Offset Output is as close to 0mV as i can get it.Still nothing.Any suggestions?I still have the donor machine, i may have to dig in to it again and salvage a few more things.../ Joakim
Hi,
isn't there a dummy DIN plug needed for the BM6000?
Linking preamp-out to power-amp-in, used to lop in an equalizer for example. Missing plug gives no signal from the selected sources to the power-amp.
Ralph-Marcus
Hi,The dummy DIN is connected, i actually didn't know there was one until i read your message and looked on my machine, but that was to easy.Although i have found the problem!I started measuring around on board 3, i figured since both channels are dead it is probably something they both have in common.I quickly discovered the 31V power to IC2 was missing.32V in on P13 was ok, but 0V after TR1.TR1 measured ok... and there it was, a short in C2!
Replaced it with 68uF (the closest i have at home), and sound started coming from the speakers :-)I realize a re-cap of the machine is necessary, but i wanted to know that it was fully functional before doing that. / Joakim
Grattis! Bra jobbat!
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