My contribution to this site...if anyone is interested. - Page 22 - 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 4th April 2012, 03:42 PM   #211
diyAudio Member
 
aptquark's Avatar
 
Join Date: Jun 2010
Location: MS
Blog Entries: 1
Quote:
Originally Posted by godfrey View Post
Who's that in your avatar? Looks like I'm missing out on a good catoon or something.
OMG...you dont know who Early is? See Squidbillies.

I think he's one of my long lost relatives.
  Reply With Quote
Old 4th April 2012, 04:13 PM   #212
godfrey is offline godfrey  South Africa
diyAudio Member
 
Join Date: Nov 2009
Location: Cape Town
Thanks, having a look now.
  Reply With Quote
Old 4th April 2012, 04:14 PM   #213
diyAudio Member
 
aptquark's Avatar
 
Join Date: Jun 2010
Location: MS
Blog Entries: 1
Quote:
Originally Posted by godfrey View Post
Thanks, having a look now.
Its insane...do you know what a "redneck" is? If not...now you will.
  Reply With Quote
Old 4th April 2012, 04:38 PM   #214
diyAudio Member
 
Join Date: Feb 2010
Last time I was in South Africa I couldnt find any rednecks. Lol
  Reply With Quote
Old 4th April 2012, 09:24 PM   #215
expert in tautology
diyAudio Member
 
bear's Avatar
 
Join Date: Apr 2002
Location: New York State USA
Quote:
Originally Posted by aptquark View Post
I thought high impedance circuits are low current, high voltage? Is the voltage carried on interconnects considered high?
The voltage is irrelevant.

The issue is shunt capacitance, impedance WRT frequency based on the reactance that the capacitance presents at a given frequency

_-_-bear
__________________
_-_-bear
http://www.bearlabs.com -- Btw, I don't actually know anything, FYI -- [...2SJ74 Toshiba bogus asian parts - beware! ]
  Reply With Quote
Old 4th April 2012, 10:04 PM   #216
diyAudio Member
 
aptquark's Avatar
 
Join Date: Jun 2010
Location: MS
Blog Entries: 1
Quote:
Originally Posted by bear View Post
The voltage is irrelevant.

The issue is shunt capacitance, impedance WRT frequency based on the reactance that the capacitance presents at a given frequency

_-_-bear
I got to go wrap my head around this...might take me a while.
  Reply With Quote
Old 4th April 2012, 10:14 PM   #217
diyAudio Member
 
aptquark's Avatar
 
Join Date: Jun 2010
Location: MS
Blog Entries: 1
Bear...how would YOU go about measuring cap.? Do you use the formula or do you have a meter?
  Reply With Quote
Old 5th April 2012, 01:55 AM   #218
expert in tautology
diyAudio Member
 
bear's Avatar
 
Join Date: Apr 2002
Location: New York State USA
meter...
__________________
_-_-bear
http://www.bearlabs.com -- Btw, I don't actually know anything, FYI -- [...2SJ74 Toshiba bogus asian parts - beware! ]
  Reply With Quote
Old 5th April 2012, 02:04 AM   #219
diyAudio Member
 
aptquark's Avatar
 
Join Date: Jun 2010
Location: MS
Blog Entries: 1
Quote:
Originally Posted by bear View Post
meter...
crap...now I have to get a meter...lol

I bet my capacitance is lower than yours ~
  Reply With Quote
Old 5th April 2012, 02:50 AM   #220
benb is offline benb  United States
diyAudio Member
 
Join Date: Apr 2010
These both measure capacitance as well as being cheap all-around DMM's, and may be good enough to be "acceptable"
Our Best Low Cost Multi-Function Digital Multimeter
Low Cost CSI2010 Digital Multimeter

I've got that first model, I paid $20 for it new, some guy had like 10 of them at a hamfest a year or two ago. I can't find it offhand to try it out, but the lowest capacitance scale should have a resolution of 1pF, which should be good enough to measure one cable as (for example, just guessing at numbers) 45pF and another as 49pF and thus the second has more capacitance, even if the exact values for each measurement are several pF off.

For real money and accuracy, I have a BK-878 digital L-R-C meter (and I know exactly where it is, unlike the other one that's floating around here somewhere), which is now sold as model BK-878B, sells in the $200 range. I bought it for measuring and matching crossover components (it's a full four digit display and has a capacitance resolution of down to 0.1pF which is overkill for most things), but incredibly I haven't made any speakers since I bought it.

I already had an old venerable GR X-Y bridge just like I had used in college decades earlier, but those things are a beast, you need both an oscillator and a meter to use it, AND you need to read the manual to know how to set the switches, and turn both dials to set the meter value to minimum measurement. It's far from intuitive, unless perhaps you used it often. Nowadays it's as much of a museum item as a piece of test equipment. There's this and a few other things I should put into a glass case.

And thanks to your recommendation, I just saw an animated version of "Smokey and the Bandit." I got my hammer down...
  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
Contribution to loudspeaker wiki? hkoetz Multi-Way 3 2nd March 2008 07:45 PM
My small contribution syn08 Solid State 15 15th January 2007 12:41 PM
audioPT's gainclone mania contribution audioPT Chip Amps 2 5th July 2005 02:58 AM


New To Site? Need Help?

All times are GMT. The time now is 09:14 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