RN-20 Chinese transformer connecting to JHL Amp board - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 16th April 2013, 12:02 AM   #1
diyAudio Member
Join Date: Apr 2013
Default RN-20 Chinese transformer connecting to JHL Amp board


I have just purchased a pre-built JHL amp board and a transformer to go with it, and I am looking for a bit of a sanity check whilst I wait for it to arrive to plan how I am going to connect things.

This is the transformer: 30W 220V R Core Transformer 9V 2 15V 2 Free Shipping | eBay

The mains side is straight forward, One to neutral, one to active, (both are red so it doesn't appear to matter which one), and grn/yel to Protective earth. So far so good.

My question really revolves around the output side. I need a 15-0-15 ac supply. My first instinct is that I take each of the yellows as a +15 and the red attached to neutral as "0". Is this correct, or do I need to take one green and one yellow as my +15's?

Is there any benefit to me putting an appropriately sized capacitor bank between the output of the transformer, and the input to the amp? Space in the enclosure isn't a problem, but if there is likely to be no benefit I wont bother!

If you could please let me know if my interpretation of the transformer is correct it would be really appreciated!
Attached Images
File Type: jpg transformer.jpg (34.8 KB, 183 views)
  Reply With Quote
Old 16th April 2013, 01:23 AM   #2
diyAudio Member
Join Date: Apr 2013
OK. Looking at pictures of these installed in finished kits, my assumptions with the outputs are clearly wrong.

Can anyone point me to a document / website / whitepaper so that I can learn how this should be wired?
  Reply With Quote
Old 16th April 2013, 02:23 AM   #3
diyAudio Member
Join Date: Apr 2013

Lets see if I got this right now....

To get the output I need, I would connect one yellow as +15, one green as +15, and the remaining yellow and green would connect together to get my 0.

Is this correct?
  Reply With Quote
Old 16th April 2013, 10:29 AM   #4
DF96 is online now DF96  England
diyAudio Member
Join Date: May 2007

Keep the reds (mains primary) well away from the secondaries. The green/yellow striped wire (screen) should attach to the grounded chassis. You should also make a connection between chassis and the circuit 0V point, but possibly not your green+yellow junction - read threads on grounding to avoid hum.
  Reply With Quote


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
In stock pcb for JHL 1969/PASS F5/NAP140/6N3 PRE-AMP/JHL headphone diyhifishop Vendor's Bazaar 6 29th August 2012 07:48 AM
Parts Express DOTD 20-0-20 200W transformer $5 officeboy Parts 20 21st June 2010 09:02 PM
Where in Brisbane can I get a transformer for my Chinese amp data Tubes / Valves 7 17th February 2008 08:50 AM
Tripath TA2020-20 6 Channel Amp Board john65b Class D 1 21st September 2005 04:43 AM
Jhl Class A Amp Pcb colin.hepburn2 Solid State 0 19th January 2003 12:34 AM

New To Site? Need Help?

All times are GMT. The time now is 08:03 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2