Check out this dangerous as all hell design. (Don't do what they do here!) - diyAudio
Go Back   Home > Forums > Design & Build > Construction Tips

Construction Tips Construction techniques and tips

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 30th December 2012, 06:52 AM   #1
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Angry Check out this dangerous as all hell design. (Don't do what they do here!)

Click the image to open in full size.

I nearly had a heart attack at the mere sight of this...

notice how the UNFUSED, UNSWITCHED, UNCOVERED 2-core mains comes directly in from the power cord to the transformer, and that its the Secondary wiring which is fused!!!!?????

As found on a Pioneer CT-W103 tape deck.
__________________
"It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away" - Antoine de Saint Exupéry
  Reply With Quote
Old 30th December 2012, 07:00 AM   #2
diyAudio Member
 
dagerman's Avatar
 
Join Date: Feb 2011
Location: Greater Seattle Area
Cost pressures...?
primary winding=fuse if anything goes south downstream; you just have to be willing to replace the $$$$ transformer instead of a .$ fuse.

I find it actually more disturbing that there is no insulation whatsoever on the solder connections that carry line voltage to protect from consequences when accidentally touching with meters, tools, hands, etc.

It seems these kinds of shortcuts become more and more common, especially since most stuff nowadays just gets kicked to the curb when it breaks, instead of being repaired. Because new is cheaper.... NOT.
__________________
There are 10 types of people: Those who understand binary and those who don't.
  Reply With Quote
Old 30th December 2012, 07:21 AM   #3
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
I can honestly say that I've never seen a consumer product that was so dangerously designed as this in all of my years of popping covers.

And there is no mains fuse underneath on the hot pcb, I checked.

I promptly double checked to see if it was unplugged and put the cover straight back on, no way I'm going to be working on this unit.

And this isn't a hack or something that has been put on afterwoods, the soldered joints look original.
__________________
"It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away" - Antoine de Saint Exupéry
  Reply With Quote
Old 30th December 2012, 07:23 AM   #4
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Nothing out of the ordinary there and tbh nothing that is dangerous to the consumer or an experienced technician. Its absolutely standard pratice, even 20 years ago or more.

The label on the rear gives all the information neccessary. No user servicable parts inside and dangerous voltages.
__________________
-------------------------------------------------------
A simulation free zone. Design it, build it, test it.
  Reply With Quote
Old 30th December 2012, 07:34 AM   #5
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
i see that in many Japanese amps and even cd players.....no biggie...
  Reply With Quote
Old 30th December 2012, 07:36 AM   #6
freax is offline freax  Australia
diyAudio Member
 
freax's Avatar
 
Join Date: Sep 2007
Location: NSW
Yeah I know.. I've seen it too mostly in VCR's, but this one is sticking right up at the top of the chassis, usually you find it somewhere hidden or out of the way..

Maybe I'm overacting a little bit but yeah... its not nice to see a big nasty active and neutral line sticking up like that.

In the pioneer you've got 3 points of contact on a pcb thats high up in the air that could potentially kill you.

This is an inch off the roof of the cover.

This is what its like in a sherwood: Click the image to open in full size.
__________________
"It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away" - Antoine de Saint Exupéry

Last edited by freax; 30th December 2012 at 07:56 AM.
  Reply With Quote
Old 30th December 2012, 08:11 AM   #7
Gyuri is offline Gyuri  Hungary
diyAudio Member
 
Gyuri's Avatar
 
Join Date: Nov 2003
Location: Budapest
The service manual shows there is a primary winding fuse in the transformer block. (at least.)
__________________
Those who would have deserved the life they are all dead already. "Oh, my dead dears!" - Captain Cat
  Reply With Quote
Old 30th December 2012, 08:15 AM   #8
Gyuri is offline Gyuri  Hungary
diyAudio Member
 
Gyuri's Avatar
 
Join Date: Nov 2003
Location: Budapest
I just sent it to you now.
It is a little bit more than nothing.
__________________
Those who would have deserved the life they are all dead already. "Oh, my dead dears!" - Captain Cat
  Reply With Quote
Old 30th December 2012, 08:15 AM   #9
just another
diyAudio Moderator
 
wintermute's Avatar
 
Join Date: Aug 2003
Location: Sydney
Blog Entries: 22
Personally I insulate with heat shrink or other means any exposed mains cabling, just to remove the chance of brushing against it when troubleshooting something with the power on. It doesn't take much and could save your life.

Tony.
__________________
Any intelligence I may appear to have is purely artificial!
Some of my photos
  Reply With Quote
Old 30th December 2012, 08:16 AM   #10
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
the fuse is actually built in at the power traffo bobbin primary, a type of non-reset-able thermal fuse, i have repaired lots of these in the past...
  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
Design Check! saggybob Multi-Way 3 4th February 2011 01:35 AM
Check this design out kornnylike Subwoofers 6 7th April 2010 07:58 PM
headamp design check. Rembrant Chip Amps 7 21st December 2008 11:14 PM
New Here. Will you check me design? SightSeeker1 Subwoofers 19 13th April 2006 03:59 PM


New To Site? Need Help?

All times are GMT. The time now is 03:00 PM.


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