R/E/P Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: Sony C38  (Read 1768 times)

JosephDeMaio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 200
Sony C38
« on: November 25, 2013, 12:47:17 pm »

Hello all,
 I have a pair of Sony C38 mics from the 70's that need jfets. Unfortunately I can't seem to find a replacement. I believe the # of the fet is CL112B, but it's a long dead number. There does not even appear to be data sheets for it anymore.
 Any help would be greatly appreciated.
Thanks,
Joe

Jim Williams

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 581
Re: Sony C38
« Reply #1 on: November 25, 2013, 01:26:14 pm »

Try a 2SK30A, the standard Japanese fet used in those days. Many more can also be used, you may need to adjust the source resistor value to obtain the sweet spot.
Logged

klaus

  • Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1826
Re: Sony C38
« Reply #2 on: November 25, 2013, 01:28:53 pm »

Or, try the current (soon obsolete again) 2N3819 from Fairchild.
Logged
Klaus Heyne
German Masterworks®
www.GermanMasterworks.com

JosephDeMaio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 200
Re: Sony C38
« Reply #3 on: November 25, 2013, 02:54:20 pm »

Thanks for the replies gents, I'll give these a try and see what happens.

klaus

  • Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1826
Re: Sony C38
« Reply #4 on: November 25, 2013, 04:07:31 pm »

As Jim mentioned: nothing good may happen until you properly bias the new FET!
Logged
Klaus Heyne
German Masterworks®
www.GermanMasterworks.com

Jim Williams

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 581
Re: Sony C38
« Reply #5 on: November 26, 2013, 12:39:08 pm »

These are also good contenders:

2SK170

LSK170, made by Linear Systems, a quieter version at 1 nv/hz/sq

J305, used by AKG and others, a faster, lower stray capacitance rf jfet. That part has a bit more top end detail than the others mentioned.
Logged
Pages: [1]   Go Up