Dx Blame MKIII-Hx - Builder's thread - Page 101 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 18th February 2012, 07:47 PM   #1001
diyAudio Member
 
Join Date: Apr 2008
This image shows the wiring...
It should allow you to use your original 12VA transformer

full-wave.jpg
__________________
Regards,
currentflow

Last edited by currentflow; 18th February 2012 at 07:53 PM.
  Reply With Quote
Old 18th February 2012, 08:30 PM   #1002
BMW850 is offline BMW850  Netherlands
diyAudio Member
 
BMW850's Avatar
 
Join Date: Aug 2004
Location: North East of the Netherlands
Hi currentflow,

Thanks for your patience, that you help me to solve this problem with the 7812 regulator and the image.
I'm waiting on email, and post the answer here.

Regards,
Rudy
__________________
Itís not what you know, but who you know ďand where they areĒ
  Reply With Quote
Old 18th February 2012, 08:50 PM   #1003
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by BMW850 View Post
Hi currentflow,

Thanks for your patience, that you help me to solve this problem with the 7812 regulator and the image.
I'm waiting on email, and post the answer here.

Regards,
Rudy
My pleasure. While you're waiting for that email, please try the diodes (if you have any).

As I see it, your options are:

a) Fit the extra two diodes and possibly increase the values of C1 & C2 to 470uF/25V each, or
b) Use a 12-0-12 transformer, connecting it to all three board terminals.

With half-wave rectification and the relatively low-value smoothing capacitors (2 x 100uF), you're just not getting enough current into the regulator.
__________________
Regards,
currentflow
  Reply With Quote
Old 19th February 2012, 10:03 AM   #1004
BMW850 is offline BMW850  Netherlands
diyAudio Member
 
BMW850's Avatar
 
Join Date: Aug 2004
Location: North East of the Netherlands
Thanks currentflow,

My intention was to 12-0-12 2A ordering, also stood on the board 12-0-12
But vintage_audio_lab told me via email that 12-0 1A was enough for this application, thats the reason why I ordered this 12-0 1A transformer.

Quote:
Dear Sir:
http://www.okaphone.nl/product/images/212048c.jpg
This transformer is 12-0-12 full wave output.
What you need should be simpler one. Just need to have one 12-0 output, 1A current is quite enough.
Sincerely, Kevin
- vintage_audio_lab
When I get no email after this weekend , I order this 12-0-12 2A transformer.
Then I take option B
b) Use a 12-0-12 transformer, connecting it to all three board terminals.

I'm still waiting on email,

Regards,
Rudy
__________________
Itís not what you know, but who you know ďand where they areĒ
  Reply With Quote
Old 19th February 2012, 10:44 AM   #1005
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by BMW850 View Post
Thanks currentflow,

When I get no email after this weekend , I order this 12-0-12 2A transformer.
Then I take option B
b) Use a 12-0-12 transformer, connecting it to all three board terminals.

I'm still waiting on email,

Regards,
Rudy
Hi Rudy,

Using option a) will cost less than 1 euro for two diodes and achieve exactly the same result. You would only need to install two diodes on one board and then connect the three power terminals of each board in parallel. This makes the most sense when you have a perfectly good transformer
__________________
Regards,
currentflow
  Reply With Quote
Old 19th February 2012, 12:04 PM   #1006
BMW850 is offline BMW850  Netherlands
diyAudio Member
 
BMW850's Avatar
 
Join Date: Aug 2004
Location: North East of the Netherlands
I tested this module also with 12v 10A torriod , and I have also a voltage drop, how do you explain this?
Sorry I question this, because my electro knowledge does not go as far to understand this

Sorry I have no diodes to test, but I will order diodes.

Regards,
Rudy
__________________
Itís not what you know, but who you know ďand where they areĒ
  Reply With Quote
Old 19th February 2012, 12:18 PM   #1007
diyAudio Member
 
Rudi_Ratlos's Avatar
 
Join Date: Jun 2009
Location: Hamburg / Germany
Rudy,

with your current implementation (you have the 2 upper diodes, D1 and D3 installed), the current does not know where to flow back.

Get the 2 diodes that CURRENTFLOW told you, solder them correctly - and you are done.

Best regards - Rudi
Attached Images
File Type: png 02042811.png (5.9 KB, 448 views)
  Reply With Quote
Old 19th February 2012, 03:44 PM   #1008
BMW850 is offline BMW850  Netherlands
diyAudio Member
 
BMW850's Avatar
 
Join Date: Aug 2004
Location: North East of the Netherlands
I have searched and found 4 x 1N4007
I have soldered 2x 1N4007, this is the result.

Before speaker protection goes on:
Regulator 7812 input, 17,34v
Regulator 7812 out, 12,10v

Speaker protection goes on:
Regulator 7812 input, 15,10v
Regulator 7812 out, 11,87v

This is much better, you see now a little voltage drop

Regards,
Rudy
__________________
Itís not what you know, but who you know ďand where they areĒ

Last edited by BMW850; 19th February 2012 at 04:10 PM.
  Reply With Quote
Old 19th February 2012, 05:15 PM   #1009
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by BMW850 View Post
I have searched and found 4 x 1N4007
I have soldered 2x 1N4007, this is the result.

Before speaker protection goes on:
Regulator 7812 input, 17,34v
Regulator 7812 out, 12,10v

Speaker protection goes on:
Regulator 7812 input, 15,10v
Regulator 7812 out, 11,87v

This is much better, you see now a little voltage drop

Regards,
Rudy
This is because before you added the two extra diodes, you had a half-wave rectifier. Capacitors C1 and C2 (both 100uF) only became charged on the positive peaks of the AC input cycle, while the negative peaks were being unused. Their values were too low to maintain the voltage in this way and were discharging faster than they were being charged.

Adding the two extra diodes causes these capacitors to charge on the negative half of the cycle as well as the positive. Therefore the capacitors are now being charged twice as often as before and you now have full-wave rectification. Increasing C1 and C2 to 470uF (25V) would improve the situation even further under load when the relays are on. I hope that makes sense.
__________________
Regards,
currentflow
  Reply With Quote
Old 20th February 2012, 05:53 PM   #1010
BMW850 is offline BMW850  Netherlands
diyAudio Member
 
BMW850's Avatar
 
Join Date: Aug 2004
Location: North East of the Netherlands
I posed this question to vintage_audio_lab,

When you look at this forum, I am busy with the speaker protection module , and measure weird things:
Dx Blame MKIII-Hx - Builder's thread
What is the utility of this 7812 regulator in this circuit, I have a voltage drop, with this 7812 regulator.

This is the answer to my question:
Dear Sir:
7812 regulator was used for dc detection and time delay circuit. And relay also need dc supply to drive it.

Sincerely, Kevin
__________________
Itís not what you know, but who you know ďand where they areĒ
  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
Dx Blame ST - Builder's thread - post pictures, reviews and comments here please. destroyer X Solid State 1730 15th September 2014 11:01 PM
Dx Blame MKIII Supercharged will soon be released destroyer X Solid State 346 22nd April 2014 04:01 PM
group buy for DX Blame MKIII Hx PCBs ByronInPortland Group Buys 247 5th December 2012 01:05 AM
Group By: DX Blame MKIII Hx boards ByronInPortland Group Buys 9 19th July 2011 08:21 AM
Dx Blame MKII, an obvious evolution from the Dx Blame ES/ST destroyer X Solid State 4 25th September 2010 07:41 PM


New To Site? Need Help?

All times are GMT. The time now is 06:41 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