I have a Kenwood Model 500 i want to keep, an heirloom piece if you will, with this I want to gather a stock of spares for it. The 2SK58 I know you get from a source but was wondering if it was replaceable? I was thinking an LSK389b? What should I be looking at specs wise to match? What do you think?
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With J-fets both Vpo and Idss are important to have an acceptable match (DC specs only, the rest is arbitrary).
If you want to replace the 2SK58, measure these specs as a reference for the replacements.
But the 2SK58's are still available: I recently purchased some 60 2SK58 (& swapped 10 with Andrew Witham, member here) for 8 euro's each!
If you want to replace the 2SK58, measure these specs as a reference for the replacements.
But the 2SK58's are still available: I recently purchased some 60 2SK58 (& swapped 10 with Andrew Witham, member here) for 8 euro's each!
So with the above datasheets idss for the 2sk58 is 1 - 16.5 so the Lsk389b would fit this with idss of 6-12? Vpo which I'm guessing is pinch off voltage? Is no good?
2SK58: Vpo = [0.45 - 4.95]V; Idss = [1.0 - 16.5]mA; S = 2.7mA/V
LSK389B: Vpo = [0.15 - 2.00]V; Idss = [6.0 - 12.0]mA; S = [8 - 20]mA/V
In this circuit, the diffpair tailcurrent is set with Re12: 15V/15k = 1mA, so 0.5mA each leg.
Course and fine balance adjustments with VRe1 and VRe3.
Given the voltage at the sources (+1.0V), the used 2SK58 is in the Vpo=2.0V range or near.
The drain voltage is set with Re3 and Re4, both 27k, yielding 10.5V.
You have to find a close fitting LSK389B. Their Idss is rather high.
LSK389B: Vpo = [0.15 - 2.00]V; Idss = [6.0 - 12.0]mA; S = [8 - 20]mA/V
In this circuit, the diffpair tailcurrent is set with Re12: 15V/15k = 1mA, so 0.5mA each leg.
Course and fine balance adjustments with VRe1 and VRe3.
Given the voltage at the sources (+1.0V), the used 2SK58 is in the Vpo=2.0V range or near.
The drain voltage is set with Re3 and Re4, both 27k, yielding 10.5V.
You have to find a close fitting LSK389B. Their Idss is rather high.
Citizen!24032, would you consider selling of those transistors to me for replacement on my two Sony TAN-5550?
Citizen!24032, I am currently under moderation so I cannot receive any messages... Could you please email me at: [REDACTED]? Thanx in advance 🙂
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