LM3875 socket - Page 3 - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 4th October 2013, 01:12 PM   #21
Jsixis is offline Jsixis  United States
diyAudio Member
 
Join Date: Feb 2011
Location: Columbus Ohio
Nice test box
  Reply With Quote
Old 4th October 2013, 01:36 PM   #22
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Quote:
Originally Posted by WSJ View Post
I found a LME49830 demo board parts list, but no socket was listed.
Do you have a link for the socket?

Thanks
The LM4702 will work in a ZIF socket, the pins of the LM3875 are staggered differently. Sorry

You could check the 3M site, or Textools. Alternately there are Mill-Max pins which could be purposed for this.
  Reply With Quote
Old 6th October 2013, 09:08 PM   #23
WSJ is online now WSJ  United States
diyAudio Member
 
WSJ's Avatar
 
Join Date: May 2009
Location: GILROY, CA
Quote:
Originally Posted by Jsixis View Post
Nice test box
Here is a link to my op amp test fixture.
Discrete Opamp test circuits

Click the image to open in full size.
  Reply With Quote
Old 6th October 2013, 10:48 PM   #24
Jsixis is offline Jsixis  United States
diyAudio Member
 
Join Date: Feb 2011
Location: Columbus Ohio
thanks!!
  Reply With Quote
Old 6th October 2013, 11:57 PM   #25
diyAudio Member
 
Join Date: Sep 2006
Location: Santa Rosa Beach, FL
Default Waht is that op amp?

WSJ..... I noticed the device under test in your post #23, marked Nexus.

Just went thru my old parts bin, and found four Philbrick/Nexis PP45U modules. They each have seven leads (+In, -In, +15v, -15v, common, output, and trim) They also have gummed labels on the side indicating Offset trim [16k], +I trim [331M] and -Trim [329M]. (The values in brackets [] vary significantly from one module to the next; these values have been handwritten on the with gummed label.)

All four appear to be unused.

Can you advise what these are (I'm assuming early Op Amps). Are they worth anything today? I'm old--please tell me they are priceless, so I can retire in style....

Thanks.... Just curious......... Didn't mean to hijack the thread....(!)
  Reply With Quote
Old 7th October 2013, 12:48 AM   #26
WSJ is online now WSJ  United States
diyAudio Member
 
WSJ's Avatar
 
Join Date: May 2009
Location: GILROY, CA
Quote:
Originally Posted by CanAm Man View Post
WSJ..... I noticed the device under test in your post #23, marked Nexus.

Just went thru my old parts bin, and found four Philbrick/Nexis PP45U modules. They each have seven leads (+In, -In, +15v, -15v, common, output, and trim) They also have gummed labels on the side indicating Offset trim [16k], +I trim [331M] and -Trim [329M]. (The values in brackets [] vary significantly from one module to the next; these values have been handwritten on the with gummed label.)

All four appear to be unused.

Can you advise what these are (I'm assuming early Op Amps). Are they worth anything today? I'm old--please tell me they are priceless, so I can retire in style....

Thanks.... Just curious......... Didn't mean to hijack the thread....(!)
Hi Jack.....No problem….
I worked at Intech in the 70’s, only 43 years ago. We made great discrete op amps, they sold for $150 - $450, at the time gas was 24 cents. Philbrick/Nexis sold similar op amps, so we evaluated the completion, most of ours were better.

Your amps may be worth putting on ebay. Do a search for discrete Op Amps and you will find some very good audio Op Amps.

The 990 Discrete Op Amp is almost exactly the same circuit as the A148 Intech, my personal favorite.
http://www.johnhardyco.com/pdf/990.pdf

The balance resistor is a selected single fixed resistor to balance the offset. The amp was made unbalanced to avoid using a pot to balance the amp, in order to keep the cost down.

Here are some Intech 10 MHz bandwidth op amps.

Click the image to open in full size.

Click the image to open in full size.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New 6C33 Socket FullRangeMan Tubes / Valves 18 3rd June 2011 03:22 PM
Socket Saver Kashmire Tubes / Valves 2 3rd January 2010 01:49 AM
Which socket for a 5Y3?? Richard Ellis Tubes / Valves 2 11th November 2008 04:41 PM
Help on tube socket dung0981 Tubes / Valves 6 5th August 2006 08:31 AM
what rca socket do you think is best?? wuffer Parts 24 25th May 2006 11:35 PM


New To Site? Need Help?

All times are GMT. The time now is 02:00 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2