umbilical for BrianGT kit - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 21st April 2005, 01:17 PM   #1
waltona is offline waltona  United Kingdom
diyAudio Member
 
Join Date: Apr 2005
Location: Up North
Default umbilical for BrianGT kit

Hi all,

I'm building Brian's 3875 kit with the power supply in a separate case to the amp boards. I'm using a tranny with dual secondaies and one rectifier board. My question is how many wires do I need in the umbilical connecting the 2 boxes? Can I combine the PG+ and PG- at the rectifier board and use one connecting wire?

At the moment I was thinking of using 1 wire for each of the following:

V+ (one wire from rectifier to amp box which is then split to each amp board)
V- (as above)
Earth (for chassis only)
PG (+ and - combined at rectifier board and split in the amp box)

I know this is a very smple question and YES I have searched the forums but I'm a bit confused and thought it was better to ask and be safe.

Thanks

BIG A
  Reply With Quote
Old 21st April 2005, 03:13 PM   #2
homer09 is offline homer09  Canada
diyAudio Member
 
homer09's Avatar
 
Join Date: Jan 2004
Location: Montreal
yes it is safe, if done properly to avoid hums. i suggest you follow carlos fm's way:

http://www.diyaudio.com/forums/showt...246#post617246
__________________
Most people wouldn't know good music if it came up and bit them in the ***. - Frank Zappa
  Reply With Quote
Old 21st April 2005, 03:48 PM   #3
waltona is offline waltona  United Kingdom
diyAudio Member
 
Join Date: Apr 2005
Location: Up North
Thanks for the reply.

Ok I'm sorted with V+, V-, PG+ and PG-.

Now about chassis ground...do I connect the mains earth to the power supply chassis, run a second wire in the umbilical to the amp chassis and not use the CHG on the PCBs?
  Reply With Quote
Old 21st April 2005, 04:16 PM   #4
homer09 is offline homer09  Canada
diyAudio Member
 
homer09's Avatar
 
Join Date: Jan 2004
Location: Montreal
sounds right, u'll know for sure when there's no hum.
__________________
Most people wouldn't know good music if it came up and bit them in the ***. - Frank Zappa
  Reply With Quote
Old 21st April 2005, 08:11 PM   #5
Nuuk is offline Nuuk  United Kingdom
diyAudio Member
 
Nuuk's Avatar
 
Join Date: Feb 2003
Location: Somerset, SW England
Quote:
Now about chassis ground.
Yes run the ground wire from the PSU chassis through the umbilical and connect it to the metal cahssis of the amp case. The connect CHG to the case via a cpa and resitor in parallel as shown in this design .
__________________
The truth need not be veiled, for it veils itself from the eyes of the ignorant.
  Reply With Quote
Old 21st April 2005, 10:12 PM   #6
Sherman is offline Sherman  United States
diyAudio Member
 
Join Date: Feb 2004
Location: Chicago area
Quote:
Originally posted by waltona
Thanks for the reply.

Ok I'm sorted with V+, V-, PG+ and PG-.

Now about chassis ground...do I connect the mains earth to the power supply chassis...
If your umbilical is relatively short (say under a meter) then a five wire DIN plug works well. In the amp box use a panel mount DIN connector. Easy to disconnect and it can't be connected wrong.

Connect 1 wire each to V+, V-, PG+, PG- and earth or safety ground in the PS box.

In the amp box make the 4 power connections to the amp boards and connect the earth or safety ground pin to the chassis.

Just make sure to match the right pins to the right PS connection!
__________________
--Sherman
  Reply With Quote
Old 21st April 2005, 11:38 PM   #7
Banned
 
Join Date: Mar 2003
Location: Lisbon, Portugal
Quote:
Originally posted by Sherman
Connect 1 wire each to V+, V-, PG+, PG- and earth or safety ground in the PS box.

In the amp box make the 4 power connections to the amp boards and connect the earth or safety ground pin to the chassis.
That's the ticket for a ground loop.
Bigger or smaller, depending on the distance between the two channels.
But always a ground loop.
  Reply With Quote
Old 22nd April 2005, 09:00 AM   #8
waltona is offline waltona  United Kingdom
diyAudio Member
 
Join Date: Apr 2005
Location: Up North
So what would you suggest Carlos?
  Reply With Quote
Old 22nd April 2005, 12:40 PM   #9
Sherman is offline Sherman  United States
diyAudio Member
 
Join Date: Feb 2004
Location: Chicago area
Quote:
Originally posted by carlosfm


That's the ticket for a ground loop.
Bigger or smaller, depending on the distance between the two channels.
But always a ground loop.

Built four amps exactly this way with no groundloop issues whatsoever. Remember your individual boxes each must have a safety ground within the box. The two can then be connected in the umbilical with no problem and the whole thing is safer.
__________________
--Sherman
  Reply With Quote
Old 22nd April 2005, 12:52 PM   #10
waltona is offline waltona  United Kingdom
diyAudio Member
 
Join Date: Apr 2005
Location: Up North
Thanks for everyones help on this one. I appreciate it.
  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
This Connector for an Amp Umbilical? pjanda1 Tubes / Valves 4 9th January 2009 09:24 PM
Design of umbilical cord Rafal Chip Amps 16 9th September 2008 01:33 AM
Neutrik XLR for Umbilical dsavitsk Tubes / Valves 14 17th August 2006 02:20 PM
Umbilical Supplies rtarbell Parts 1 9th March 2006 10:47 PM
Umbilical cord suggestions Stever Chip Amps 6 12th December 2003 08:22 AM


New To Site? Need Help?

All times are GMT. The time now is 08:09 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