Modern replacement for a Thyristor

[SkyWay]

Hello everyone, i´m currently restoring a vintage 1,978 Pioneer SA-606 Amplifier and I´m having a hard time trying to get a Thyristor part number BCR 3AM-4 witch of course is discontinued. Can any of the experts around here point me in the right direction on suggesting a modern replacement part?


Thanks in advance.


SkyWay

 

[Enzo]

Schematic? Where is it in the circuit and what does it do? Thyristor is a term that covers a number of kinds of parts.

 

[duncan2]

SkyWay its a 3amp Triac 400V-600V-- Mouser doesn't stock 3 amp but they stock 4amp -


4 A 600 V Triacs | Mouser United Kingdom


Although it says UK its actually Mouser USA .


For those querying this -
BCR3AM Datasheet, PDF - Alldatasheet

 

[MAAC0]

It's not a Thyristor but a Triac. It's used as a crowbar speaker protection. Schematic on Hifi-engine site.
I replaced mine on the same amp with an ordinary lighting BT13X type.
I will probably order one from Wagner
BCR3AM-8 Thyristors, Triacs And Scrs, Triacs | Wagner Online Electronic Stores
Be careful with the 3 diode series array under the heatsink, those are unobtanium. If the legs break, the amp will try to smoke the output drivers.

 

[Mark Tillotson]

Perhaps better to add a separate speaker relay module if there's room, the crowbar circuit is liable to destroy itself as it discharges the +ve to ground, dumping that filter cap's energy into the triac and forcing the power amps into asymmetrical state, from what I can see of the circuit.


The fact the triac needs replacing indicates its not able to survive this destructive feat, and the manual says it will blow the mains fuse in 2 seconds.


Good speaker protection is a lot faster than that.

 

[SkyWay]

Wooow, what a helpful place here, I appreciate you guys take the time to read my post and reply
.
Looking at the service manual, the part is listed as a 200Volts 3 Amps Thyristor, do you guys think it is possible to replace with part number 2N6071AG witch is a 200 Volt 4 Amps Triac from ON semiconductors?


Thanks in advance, your help is well appreciated.




SkyWay

 

[SkyWay]

What would be the better option to replace this part?
Since the original one is rated at 200Volts 3 amps
Reaplace with a part with the same voltage and more amps or replace with a part with more volts and the same amps?.


Again any help is well apreciated.


SkyWay

 

[duncan2]

Uprate to higher current & voltage its only pennies difference in price .


You don't have to go too high just a bit higher in both but Mark does have a point .