Convert mini Pre-amp from AC to DC power - Page 2 - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, 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 25th November 2012, 12:53 AM   #11
diyAudio Member
 
Join Date: Jul 2012
Location: Draper Utah
I tried to bypass the regulator and that still does not work. I bypassed the pre-amp to make sure my source and amp were working and everything is good. I also checked my supply voltage and its perfect.

Hopefully there is some way??

Or I guess I need to find another solution. I need a small pre-amp for my amplifier.

MP
  Reply With Quote
Old 25th November 2012, 06:15 AM   #12
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
You must be doing something wrong, or something is being overlooked by someone.

I took another look at the preamp board - bridge rectifier, feeding the 78L12 and 79L12 regs, powering the single DIP8 op amp package. Sorry, but my money's on the former.
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine

Last edited by sofaspud; 25th November 2012 at 06:17 AM.
  Reply With Quote
Old 25th November 2012, 10:25 AM   #13
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
blown opamp due to error in trying to connect the wrong PSU at the start.
__________________
regards Andrew T.
Sent from my desktop computer using a keyboard
  Reply With Quote
Old 25th November 2012, 07:41 PM   #14
diyAudio Member
 
Join Date: Jul 2012
Location: Draper Utah
Quote:
Originally Posted by sofaspud View Post
You must be doing something wrong, or something is being overlooked by someone.

I took another look at the preamp board - bridge rectifier, feeding the 78L12 and 79L12 regs, powering the single DIP8 op amp package. Sorry, but my money's on the former.

Sofaspud,

Are you saying it should work with DC power supply? Or do you think its possible that I blew the op amp like AndrewT says?

Mike
  Reply With Quote
Old 25th November 2012, 09:31 PM   #15
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
It is made to work with DC. This mod was only providing the DC differently.
It may be possible. I don't know what you've hooked up to the circuit trying to get it to work.
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  Reply With Quote
Old 9th September 2015, 02:48 PM   #16
asilker is offline asilker  United States
diyAudio Member
 
asilker's Avatar
 
Join Date: Sep 2015
Location: Chicago IL
I ordered the same kit and I'm trying to figure out how to power it. As I'm new to electronics, I'd be interested to hear if you figured this problem out.

My plan was to power the board with a laptop power supply, but it seems the DC voltage is not compatible with the stock board and I should look for a 12-0-12 power transformer with low amp rating?

help I'm an electronics baby!
  Reply With Quote
Old 9th September 2015, 03:12 PM   #17
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
To use a DC source such as a laptop power brick you need either a negative rail generator or a supply splitter.

Or a 12-0-12 transformer. The board already has bridge rectifier and smoothing capacitors.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, modules and more.
  Reply With Quote
Old 9th September 2015, 03:29 PM   #18
asilker is offline asilker  United States
diyAudio Member
 
asilker's Avatar
 
Join Date: Sep 2015
Location: Chicago IL
Quote:
Originally Posted by richie00boy View Post
To use a DC source such as a laptop power brick you need either a negative rail generator or a supply splitter.

Or a 12-0-12 transformer. The board already has bridge rectifier and smoothing capacitors.
Thanks for the clarification. I just ordered a 12v-0-12v transformer. I'm really excited about trying this project. I'm a little nervous that none of this will work and I'll have to scrap it, but I'll be awfully proud of myself if I can make a functional piece.
  Reply With Quote
Old 9th September 2015, 03:34 PM   #19
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
Isolated DC-DC converters in handy for applications like this....

Astec Dual DC DC Converter 9 18V 1 23A to 12V 230mA AA05E 012L 120D | eBay

Some external filtering cleans up the small amount of ripple/noise quite well and their small size is a bonus.
  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
Convert Gates pre-amp to DC filament? slor Tubes / Valves 16 29th October 2011 05:18 AM
chip amp with 12v DC AND 240v AC power supplies? Vital AV Chip Amps 19 15th November 2009 11:39 PM
we can offer power module of DC/DC Converter & AC/DC Adapter auling Vendor's Bazaar 0 12th May 2009 04:48 AM
Convert Dac from AC to Battery Power recca Power Supplies 2 20th August 2007 01:25 AM
Combined PFC AC/DC & DC/DC SMPS ChocoHolic Power Supplies 33 22nd December 2005 11:04 PM


New To Site? Need Help?

All times are GMT. The time now is 03:37 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright 1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki