Re: Need more help.

To: tesla-at-pupman-dot-com
Subject: Re: Need more help.
From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Tue, 11 May 1999 18:55:42 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Hi Gary,
          It is possible that the numbers on your transistors are 
manufacturing batch numbers rather than the more familiar type 
numbers. If you post what you have, I'll do my best to identify them.
A cheap multimeter probably wouldn't give you the accuracy you need 
to determine the emitter ballasting resistances. They can be 
considerably less than 0.1 Ohm in some applications. It may even be 
that they are tinned copper wire. If you can solder using ordinary 
60/40 cored solder, they aren't nichrome. 

Malcolm

> Original Poster: gweaver <gweaver-at-earthlink-dot-net> 
> 
> I am still working on my TC project and need some more help.
> 
> Does anyone have any data on the resistance of nichrome wire.  I think
> nichrome is spelled wrong.  
> 
> I found several heat sinks at the scrap yard with several power transistors
> paralleled on the heat sinks.  The Emitters are connected in parallel with
> what appears to be a piece of .065 diameter nichrome wire.  I figure the
> nichrome wire serves at a resistor for each trasistor.  If this is true I
> will not have to buy several .1 ohm resistors for each transistor emitter.
> It is 1.125" between each solder connection. 
> 
> Is there any way to tell if this wire is really nichrome wire?
> 
> I checked the wire with an ohm meter and got zero resistance across a length
> of about 5" using a cheap $15.00 ohm meter. The meter is accurate enough to
> read a 1 ohm resistor.
> 
> I can't find the transistor number in any of my books.  Thats OK I can
> replace them with my other transistors if they all fry after I try them. 
> 
> Gary Weaver
> 
> 
>