AOA Forums AOA Forums AOA Forums Folding For Team 45 AOA Files Home Front Page Become an AOA Subscriber! UserCP Calendar Memberlist FAQ Search Forum Home


Go Back   AOA Forums > Hardware > General Hardware Discussion

General Hardware Discussion Hard drives, CD, DVD Monitors, All hardware questions not better served by our other Topics


Reply
 
LinkBack Thread Tools Rate Thread
  #1 (permalink)  
Old 27th August, 2002, 03:23 PM
surlyjoe's Avatar
AOA Staff
 
Join Date: September 2001
Location: caliland
Posts: 2,723

steel or aluminum case...which will sheild RF better?

I am building a rig for a guy to do studio music on, he's concerned about RF sheilding, and wants to know which is gonna be better, steel or Alu? TIA!!
__________________
"Many people die at twenty five and aren't buried until they are seventy five"
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #2 (permalink)  
Old 27th August, 2002, 04:56 PM
JigPu's Avatar
Member
 
Join Date: August 2002
Posts: 29

I honestly don't know, though the case that conducts electricity better should. Also, I think you will need the case itself grounded to make a sheild. My guess... Aluminum. But of course I could just be saying it cuz it looks so cool!

Jigpu
__________________
- OCForums Member -
(I come here when it's down or nothing's going on )
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3 (permalink)  
Old 27th August, 2002, 07:18 PM
The Spyder's Avatar
Member
 
Join Date: September 2001
Location: Oregon
Posts: 4,086
Send a message via AIM to The Spyder Send a message via MSN to The Spyder

Ya know ive built with both for people working in studio music..... and you could not tell the diff- but at the time steel is what was "cheaper" because these were already $4400 computers :-) -
__________________
~The Spyder~
I7 965, 6gigs, ASUS, 4870 X2, WD640 AALS Lian Li PC65
Nikon D700, 24-70, 70-200 2.8, SB 800x2
1993 Mazda Rx7 R1 345whp. 2008 Mazda 3 Hatch
AOA Team fah
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4 (permalink)  
Old 27th August, 2002, 08:52 PM
Chief Systems Administrator
 
Join Date: September 2001
Location: Europe
Posts: 13,075

As far as RF sheilding is concerned, it makes no difference if you use steel or aluminium. What does make a difference is if there are any holes in the case, and if there are RF sealing gaskets around any joins in the metal.

An RF sealing gasket will be a) two very very close metal surfaces running in parallel, with a very good connection between the two to earth; b) A fine metal mesh (woven from strands of around 0.02inch); c) a woven mesh filled with an elastomer (allows for compression joints)

In terms of holes, any opening over 0.6mm will leak RF. This means any ventilation slots will need to have holes of less than 0.6mm! Any joins between the motherboard shielding and the case need to be in good contact, preferably with RF sealing gasket, rather than just in contact.

In terms of construction, the preference is welding, brazing, soldering then riveting. (In order from most effective to least effective)

Most RF sealed boxes are also coated internally with nickel, which provides most of the RF sealing abilities.

RF sealing is a pretty serious bit of work, and I don't know of any cases that would meet proper RF sealing.

Note: the 0.6mm is for attenuation of up to 10GHz signals. These would be easily generated as 10th order harmonics from a device running at 1GHz. Scary!

AidanII
__________________
Any views, thoughts and opinions are entirely my own. They don't necessarily represent those of my employer (BlackBerry).
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5 (permalink)  
Old 27th August, 2002, 09:42 PM
Banned
 
Join Date: September 2001
Posts: 5,957

[lifts jaw back into place]

Amazed once again Aidan
__________________
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6 (permalink)  
Old 28th August, 2002, 02:04 PM
surlyjoe's Avatar
AOA Staff
 
Join Date: September 2001
Location: caliland
Posts: 2,723

thanks man!! :-D
__________________
"Many people die at twenty five and aren't buried until they are seventy five"
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7 (permalink)  
Old 28th August, 2002, 02:29 PM
Orbit's Avatar
Member
 
Join Date: January 2002
Location: New Mexico
Posts: 466
Send a message via ICQ to Orbit Send a message via Yahoo to Orbit

(hand goes over head)

Man, AidanII, how do you know this stuff? They teach this in some school? ~whew~
__________________

A Chieftec with a bunch of PCB's, Drives, Cables, and Water

-----------------------------------------------------------
Laws are for the lawless, who disregard them anyway... Crow
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #8 (permalink)  
Old 28th August, 2002, 03:55 PM
JigPu's Avatar
Member
 
Join Date: August 2002
Posts: 29

I forgot most of that stuff... Though now that you say it, I remember it again! Thanks!

Although I wouldn't think a 10th order harmonic would be that strong.... But hey, I did forget this stuff

JigPu
__________________
- OCForums Member -
(I come here when it's down or nothing's going on )
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #9 (permalink)  
Old 29th August, 2002, 09:32 AM
Chief Systems Administrator
 
Join Date: September 2001
Location: Europe
Posts: 13,075

Quote:
Originally posted by JigPu
Although I wouldn't think a 10th order harmonic would be that strong...
It shouldn't be that strong, but with faster and faster CPUs coming up, 10GHz not really going to be 10th order much longer. With a 3GHz CPU, we're coming close to a 3rd order harmonic instead!

Orbit - One of the companies I worked for decided to do EMC testing of their own products. We had a RF quiet room, and all the analyser tools to do the compliance testing. Although I wasn't directly involved in the EMC testing, I knew the guys quite well and discovered lots...

Like how hard it is to prevent a steel room from resonating..

AidanII
__________________
Any views, thoughts and opinions are entirely my own. They don't necessarily represent those of my employer (BlackBerry).
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Rate This Thread
Rate This Thread:

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 Off
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
NZXT Zero Black/Silver Aluminum ATX Full Tower Case @ $119.99 danrok Online Deals, and Steals 0 5th July, 2007 08:35 PM
Antec Super Lanboy Aluminum Super Mini Tower Case $39.99 after rebate mookydooky Online Deals, and Steals 0 2nd January, 2005 06:13 PM
Modding an aluminum case BMORIN Case Modifications 13 11th February, 2003 02:03 AM
Aluminum Case & good Ventilation Help COOL'n Chieftec & Epox 8RDA+ Ol'Pal Gary Case Modifications 9 30th December, 2002 06:03 AM


All times are GMT +1. The time now is 06:12 PM.


Copyright ©2001 - 2010, AOA Forums
Don't Click Here Don't Click Here Either

Search Engine Friendly URLs by vBSEO 3.3.0