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Sziasztok . Gondoltam megosztom veletek ezt a kapcsolás gyűjteményt. Sok sok zenekari és hifi erősítő rajza megtalálható. mérete miatt nem tudtam feltölteni a tanyára. http://data.hu/get/5420304/Professional__Power_Amplifiers_Chematics_Disk.rar üdv:hifi64

Üdvözlet Mindenkinek! Segítséget szeretnék kérni a fenti géphez. Bekapcsoláskor demóban működik , nem reagál a gombokra ,rádióra nem kapcsol. CD-lemezt /beveszi-kiadja/ elindítja és lejátsza ,kb. negyed hangerőn szól. Végfok benne a TDA 8588 BJ/R1 (kézzel nézve párperc múlva kicsit mindha jobban melegedne a többi végfoknál) tápfeszültség regulátoros. Feszültségek stimmelnek a gépkönyv szerint. Minden segítséget köszönettel veszek.

Want to share: Have downloaded the schematics from this forum to help repair the amplifier of a friend. Turned out that Sony decided to route the earth through the chassis, even the earth between the various supplies. When one takes the main board out of the chassis and switches the amp on, there are up to 20 volts difference between the eart (and hence reference) of the pre-amps and the main amps. Luckily the amp goes into protection but from a design point of view it is not nice to rely on screws and aluminum face plates to conduct up to 0.2 amps of current from one supply to another. What I did is solder wires to every eart point and connected them on the main board to make it stand alone and not rely on conducting current through the chassis anymore. Bad design, simple repair but took some digging in the schematics to find out what exactly was going on!

Hi All,


I have a Rotel RA-980BX amp with a blown channel. I have sourced most of the transistors, but am struggling to find the other 4.


Part numbers as follow:
2SC3478
2SC4381
2SA1376
2SA1667


What would be suggested equivalents / suitable replacements?


Also, some advice, I suspect the bias pot to be bad. Based on the circuit, would you think that the bad bias pot would cause the drivers and outputs to blow? Any suggestion on modification to prevent this re-occurring?


Thanks



Regards,
Werner