WTB: 2N5087 matched pair

[nanchangbob]

WTB: 2N5457 matched pair

I have all my parts for the Marsh headphone amp but I haven't found any real 2N5457's I bought two batches and when I tested IDSS they tested bad. Does anyone have a pair for sell or trade?

 

[simon7000]

2N5087s are PNP bipolar junction transistors. They are not junction field effect transistors. So you need to look at the schematic a bit more.

 

[wrenchone]

There's no such thing as IDSS for2N5087s - They're low noise, high HFE PNP bipolars, common as dirt. They should read open circuit collector to emitter, and have a diode drop from base to emitter. Looking at the flat face of the device, the pinout is EBC (left to right).

 

[simon7000]

I think you want 2N5457 or 2SK170s for the input FETs.

 

[wrenchone]

The Marsh headphone amp uses 2N5087 and 2N5088 at the inputs, PNP and NPN bipolars - no fets.

 

[nanchangbob]

2N5457

Yes I made the correction. I was sitting at work and typed the wrong part. It is the 2N5457 N channel FET. My mistake😱