UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Technics SU-V60. Voltage regulator

orbanp1 · 7th Apr 2019, 10:21 pm

Hi SJM,

As mentioned, the FETs have quite a variation in their parameters.
Generally FETs of the same model number are ranked according to their Idss values. Do check the datasheet.
For the 2SK301 the Idss groups are:
P: 1ma - 3mA, Q: 2mA - 6mA; R: 5mA - 12mA; S: 10mA - 20mA.
For the 2SK246:
Y: 1.2mA - 3mA; GR: 2.6mA - 6.5mA; BL: 6mA - 14mA.
So pick the FET accordingly.

The 470 Ohm resistor would just drop some voltage, the FET should not be damaged without it when you measure the Idss.

Regards, Peter

7th Apr 2019, 10:21 pm	#6
orbanp1 Heptode Join Date: Nov 2009 Location: London, Ontario, Canada Posts: 675	Re: Technics SU-V60. Voltage regulator Hi SJM, As mentioned, the FETs have quite a variation in their parameters. Generally FETs of the same model number are ranked according to their Idss values. Do check the datasheet. For the 2SK301 the Idss groups are: P: 1ma - 3mA, Q: 2mA - 6mA; R: 5mA - 12mA; S: 10mA - 20mA. For the 2SK246: Y: 1.2mA - 3mA; GR: 2.6mA - 6.5mA; BL: 6mA - 14mA. So pick the FET accordingly. The 470 Ohm resistor would just drop some voltage, the FET should not be damaged without it when you measure the Idss. Regards, Peter