I got myself a beautifull SA-7500 amplifier, still in good working condition.
I've cleaned all the pots and switches ultrasonicly. Also I've recapped all the boards, replaced the 2SC1451 transitors with the KSC3503, the 2SA725/2SA726 with KSA992 and the 2SC1312/2SC1313 with KSC1845 because I've read they can become trouble.
But now I found two 2SK34 n-fets (Q1 and Q2) on the Control Amplifier Board.
According to the Jaeger Elektronik table the 2SK34 is listed as (LF,Uni, 30V, Idss=0.3...12mA, Up=0.3...6V) and a possible replacement is BF245 (NF/HF...VHF, 30V, Idss>2mA, Up<8V) or 2SK381 (Uni,50V, Idss>0.3mA, Up<6V). But when I search the forums here I find that the 2SK34 is 50V. Is it possible to use the BF245 replacement in this situation (they are easy to get here in Europe)? I can't read schematics so I don't know whats the purpose is of the fet in the Control Amplifier.
I've cleaned all the pots and switches ultrasonicly. Also I've recapped all the boards, replaced the 2SC1451 transitors with the KSC3503, the 2SA725/2SA726 with KSA992 and the 2SC1312/2SC1313 with KSC1845 because I've read they can become trouble.
But now I found two 2SK34 n-fets (Q1 and Q2) on the Control Amplifier Board.
According to the Jaeger Elektronik table the 2SK34 is listed as (LF,Uni, 30V, Idss=0.3...12mA, Up=0.3...6V) and a possible replacement is BF245 (NF/HF...VHF, 30V, Idss>2mA, Up<8V) or 2SK381 (Uni,50V, Idss>0.3mA, Up<6V). But when I search the forums here I find that the 2SK34 is 50V. Is it possible to use the BF245 replacement in this situation (they are easy to get here in Europe)? I can't read schematics so I don't know whats the purpose is of the fet in the Control Amplifier.
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