Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 2nd October 2012, 12:13 AM   #11
diyAudio Member
 
Join Date: Feb 2012
Is that made by Belken? I may buy a bunch just to practice on.
  Reply With Quote
Old 2nd October 2012, 12:18 AM   #12
Apex Jr is offline Apex Jr  United States
diyAudio Member
 
Join Date: Jun 2002
Location: Torrance, Calif
No... I'm not at my warehouse but would think it is made
by Thermax and is a Mil-Spec wire
  Reply With Quote
Old 2nd October 2012, 11:06 AM   #13
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
RCAs are not constant impedance, unlike a well-made BNC, so the quality of the cable becomes almost irrelevant when compared with unavoidable reflections at the plugs/sockets. Should not be a problem, but absolutely no point in worrying about the cable when you have to use the 'wrong' connectors on the end.
  Reply With Quote
Old 2nd October 2012, 12:17 PM   #14
marce is offline marce  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Location: Blackburn, Lancs
Quick question, RE: the earlier link, how do the bass frequencies know how togo downthe tin plated copper and how do the highs know to go down the silver plated wires. just curious.
For digital signal transmissionas DF96 stated, impedance mismatches are much more serious to signal degredation than whether the wire is copper, silver or silver plated copper. For Mil spec cables silver plating is for temerature range of the cable, not for any signal improvements.

Last edited by marce; 2nd October 2012 at 12:32 PM.
  Reply With Quote
Old 2nd October 2012, 12:27 PM   #15
Einric is offline Einric  United States
diyAudio Member
 
Einric's Avatar
 
Join Date: Feb 2011
Location: Bozeman, MT
Any transmission over coaxial cable is carried via the center conductor.
The outer shield is just that, A Shield, it does not carry any signal.
The shield is an integral part of the cable that serves to help set the impedance of the cable.
  Reply With Quote
Old 2nd October 2012, 12:33 PM   #16
marce is offline marce  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Location: Blackburn, Lancs
Nope totaly wrong, the outer shield in a standard co-axial carries the return current, the return current is as critical as the normal signal especially in digital.
  Reply With Quote
Old 2nd October 2012, 12:45 PM   #17
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Yes, the inside of the shield carries exactly the same signal current (but inverted) as the centre conductor. That is how coax works! In a well-made coax, properly used, the outside of the shield carries no current.
  Reply With Quote
Old 2nd October 2012, 12:52 PM   #18
Einric is offline Einric  United States
diyAudio Member
 
Einric's Avatar
 
Join Date: Feb 2011
Location: Bozeman, MT
I work with coaxial cable on a daily basis.
I can take two radios and connect them with the removed center conductor of coaxial cable the transmitter of one to the receiver of the other.
I can generate a 1khz tone that is carried on 155MHz with 2.5Kc of deviation and there is no measurable loss between the two radios even with 50' of coax center without the shield other than the cable loss itself.
If I add the outer shield I get the same results.
The same holds true with my preamp to amp, I have only connected the center pin on the RCA's and did not lose anything from not having the shield.
  Reply With Quote
Old 2nd October 2012, 01:25 PM   #19
marce is offline marce  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Location: Blackburn, Lancs
Look up digital or analogue signal transmission, there HAS to be a return current path.
You must be completing the loop some other how, cos current wont flow down wires without a return path, so it will find one. Your pre-amp toamp is probably using the saftey earth connection, rf uses the real earth I believe as a reference plane.
So the signal will find a return somehow,otherwise it aint going no where.
  Reply With Quote
Old 2nd October 2012, 02:37 PM   #20
diyAudio Member
 
s3tup's Avatar
 
Join Date: Dec 2004
Location: Israel
At such frequencies the return currents find their way home by their own - usually thru air - parasitic capacitances or RF emissions. The "shield" just helps the currents to return, making-up the least impedance path which they tend to follow.
__________________
The missing link between lead and gold in alchemist's world was BS and commerce.
  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
Northwest Analogue Gold Plated Pure Silver Digital Coax dominic harper Vendor's Bazaar 0 8th November 2011 09:12 PM
FS: Hawthorneaudio Silver IRIS 15" coax drivers UK barackuda Swap Meet 6 28th August 2008 09:46 PM
Digital Coax to 5.1 Analog? ak_47_boy Digital Source 9 16th November 2006 02:24 PM
DIY Digital Coax ralph-bway Everything Else 1 9th July 2004 07:03 PM
Coax digital out to computer hoongern Digital Source 3 27th February 2004 09:16 PM


New To Site? Need Help?

All times are GMT. The time now is 11:18 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