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
Hi all,
I'm struggling with a Beomaster 5500 which has a power supply problem. The 8 volt power is not present, and I noticed a crack in a connection to the emitter of transistor 2TR12. I did repair this connection but unfortunately it doesn't work. So now my next plan is to replace 2TR12, but I think this transistor was already replaced by the previous owner (that's why the print has damaged)
According to the schema it should be a BC534, but I doubt if this is correct, because this is a tiny TO92 transistor. It should be a PNP transistor in a TO220 housing. In the unit was a BD242C, but this doesn't work.
I have another Beomaster 5500 , so I opened this unit and I noticed a BD536. This unit works.
So the big question, which transistor to use for 2TR12
- BC534 according to schema (unlikely)
- BD242C which was in this unit (faulty?)
- BD536 which is in the working unit
BC534 is a typo. BD534 sounds right. As does BD536.There are lots of typos in the manuals, it's usually best to trust what the factory fitted.
Martin
Thanks a lot, I'll try a BD536
Replaced the 2TR12 with a BD534 (found one in a donor Beomaster 5000) en fixed 2 defective connections on the print.
The 8 volt power is restored with these repairs. Now I need to address other problems, for 1 of these problems I create a new thread
Thanks again for the information.