wire wound resistor - Page 3 - diyAudio
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 18th December 2012, 04:02 AM   #21
MGH is offline MGH  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Texas
Quote:
Originally Posted by The Space Egg Corp View Post
Yeah...
...loads of schematics like that posted on the net all the time...
...but anyhow...
...what amp is it anyway ?

Schematic will be on Google for sure.

Cheers.

Si.
Please see my PM. Thanks.
  Reply With Quote
Old 18th December 2012, 04:09 AM   #22
MGH is offline MGH  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Texas
Quote:
Originally Posted by DF96 View Post
The 2.2k resistor is a grid stopper. It reduces the RF gain of the valve so it can't turn into an oscillator. A non-inductive wirewound might not be best here, because it could have too much capacitance. Just use a carbon film or metal film.
Hi DF96, a grid stopper...that's what it's called, and thanks for explaining the purpose of this resistor, to prevent oscillation. I tend stay away from carbon film because of my concern for instability but many seem to like carbon film or composite in this position. Do you have a particular brand of carbon film or metal film in mind? Your experience on this matter would be appreciated.
  Reply With Quote
Old 18th December 2012, 12:47 PM   #23
diyAudio Member
 
The Space Egg Corp's Avatar
 
Join Date: Sep 2010
Location: London & Miami
Blog Entries: 13
If you want the only carbon worth 'sniffing at' IMO...
...check out 'Kiwame' carbons.

Si.

Carbon - Vintage sound.
Metal film - Edgey sound.
Wire wound - Wire sound.

More useless hyperbole probably.......................................... .
  Reply With Quote
Old 18th December 2012, 06:30 PM   #24
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Originally Posted by MGH
I tend stay away from carbon film because of my concern for instability but many seem to like carbon film or composite in this position. Do you have a particular brand of carbon film or metal film in mind? Your experience on this matter would be appreciated.
Instability? Are you getting carbon film and carbon composite mixed up? The latter can be unstable, over periods of decades. Some people prefer carbon comp for stoppers, but I don't think this is necessary.

I don't worry about brands. The circuit is far far more important than component brand. Many (but of course not all) of those who worry about brands do so as a substitute activity for their lack of circuit knowledge, in my opinion.
  Reply With Quote
Old 18th December 2012, 06:50 PM   #25
MGH is offline MGH  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Texas
Quote:
Originally Posted by DF96 View Post
Instability? Are you getting carbon film and carbon composite mixed up? The latter can be unstable, over periods of decades. Some people prefer carbon comp for stoppers, but I don't think this is necessary.

I don't worry about brands. The circuit is far far more important than component brand. Many (but of course not all) of those who worry about brands do so as a substitute activity for their lack of circuit knowledge, in my opinion.
You're right, I was thinking of carbon comp being unstable.
  Reply With Quote
Old 18th December 2012, 07:08 PM   #26
JMFahey is online now JMFahey  Argentina
diyAudio Member
 
JMFahey's Avatar
 
Join Date: Mar 2009
Location: Buenos Aires - Argentina
Quote:
...make your own resistors...
..." now that's DIY dude ! "
Flat-wound...& more acurrate than Vishay-foil...
...$$$$$$$$$$$$$$$$$$$$$$$ left over, to buy LP's with !
Do you find this unusual?
Not so
I have been making my own for ages (think thousands of them, for over 30 or 32 years).
For both reasons: nil cost, but the main one is getting them in any odd value, such as .065 ohms , perfect for limiting at exact 10 A in short protection circuits.
I buy 0.50 mm diameter Constantan (although now it comes under the commercial brand CuNi44), which is solderable.
Casa Astri - Proveedores Industriales - Resistencias Electricas - Aislantes Térmicos - Instrumentos de Medición - Controles de Temperatura - Tubos de Cuarzo - Cerámicas Tecnicas - Caloventores - Calefactores Electricos - Bimetales - Pantallas Ifrarro
.065 ohms is a short strip measuring 1 inch , as easy as they come.
I have 2 pads on the PCB separated by 20 mm, so the wire is parallel to it , 5mm away.
Wire resistance is 2.5 ohms/Meter , very easy to calculate.
So 0.1 ohms means 4 cm and so on.
100 grams of wire cost a few dollars and provides 1 year supply, how's that?
For higher values (0.33 ohms ; 0.47 ohms) I flat wind them around strips of "micanita" , a flat sheet material made out of mica.
Casa Astri - Proveedores Industriales - Resistencias Electricas - Aislantes Térmicos - Instrumentos de Medición - Controles de Temperatura - Tubos de Cuarzo - Cerámicas Tecnicas - Caloventores - Calefactores Electricos - Bimetales - Pantallas Ifrarro
  Reply With Quote
Old 18th December 2012, 09:35 PM   #27
MGH is offline MGH  United States
diyAudio Member
 
Join Date: Jul 2004
Location: Texas
Are Kiwame resistors carbon comp or film? According to Partsconnexion they're carbon film.

KIWAME - 5 Watt Carbon Film Resistors
  Reply With Quote
Old 18th December 2012, 09:55 PM   #28
diyAudio Member
 
Triodethom's Avatar
 
Join Date: Dec 2009
Location: Newnan GA
as DF96 pointed out it a grid stopper resistor . Thus some inductance the small amount in those values should reduce not increase rf pass through . As for the plate and screen resistors more inductance is desired. Transformer coupled outputs state an inductance value , it part of how they work . All the signal passes through the grid resistor so try some ans see what you think.
  Reply With Quote
Old 18th December 2012, 10:05 PM   #29
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Originally Posted by Triodethom
As for the plate and screen resistors more inductance is desired. Transformer coupled outputs state an inductance value , it part of how they work .
Audio transformers typically need many 10's or 100's of H. Resistors, whether wirewound or not, are going to be in the uH or nH region so won't contribute much inductance.
  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
Just tried a Wire Wound pot for volume. Shoog Tubes / Valves 6 9th April 2012 10:43 PM
Wire Wound Resistor or Inductor? 69stingray Parts 5 30th January 2010 01:24 AM
Why not wire wound potentiometers for volume? tem00 Chip Amps 18 16th January 2009 01:48 PM
Wire Wound Pontentiometers - resistors neazoi Tubes / Valves 1 12th January 2009 11:08 AM
Wire Wound Resistor Failure? jjai Solid State 6 3rd March 2005 07:32 PM


New To Site? Need Help?

All times are GMT. The time now is 11:57 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