Topic: Replacement FET for Nak300 Teac Tascam mics??

[Scooter]

Anybody know the correct replacement FET??

[Roving Sign]

My TEAC ME-80s say

"K30A"

I actually found the spec sheet once upon a time...pretty sure I fried one of mine.

[Church-Audio]

Anybody know the correct replacement FET??

Just a bit of advice if your going to replace the fet do it in both mics and buy enough so you can match them. They can be way off from each other and knock your mics way off too.

Chris

[Scooter]

will do.

[Roger Gustavsson]

The JFET inside the Primo/Nakamichi/Teac/Altec/LEM microphones are 2SK30ATM-O (Idss=1mA) and later ones have 2SK118-O (Idss=1mA). These are hard to find. 2SK118-R (Idss=0.5mA) seems to be easier. I have found the SMD-version 2SK208-O. I think you can modidify the circuit. A good choice can be the 2SK222 but they are also hard to find. I bought mine from China. Are you running your microphones with the transformers? You can leave them out if cables are short and you will have a hotter output (about 11-14dB). There are lot of modifications that can be done. Take a look at the micbuilder forum.

Roger

[Scooter]

they are indeed modded already.  thanks for the info!

[Roger Gustavsson]

Hi Scooter,

In what way are yours modded? Only "actives" or even more? I wished the output was hotter. The original PCB could be replaced with different circuit, like the one Schoeps uses, phantom powered (I prefer from an internal 12V battery). I have no experience of working with surface mounted devices, so far it is only in my head... Output will be raised from 1.6mV (original with transformer) to about 10.3mV (double of "actives"). That is 16dB hotter.

Roger

[Scooter]

they are "actives".  running on 9v from samson pm-4's.  one of them is wonky, just trying to figure out what is wrong.