[sdiy] Expo Converter and Tempco

[James Patchell]

Tel Labs is no longer really around (well, they are, but absorbed by 
somebody else...Vishay I think).  KRL also makes tempcos...somebody on the 
list just got a bunch made...but you need to order a min of 100 pieces or 
so from KRL if you are going direct.

This is how I solved the Tempco problem: 
http://www.noniandjim.com/Jim/synthmodulesII/200-1007.pdf

Ian Fritz also came up with his own way to solve the problem using Tempcos 
with other temp coeficients.

At 08:35 AM 11/10/2006 -0800, you wrote:
>Hi,
>
>We finally settled for the ENS-76 option 1 VCO as our base design, it can be
>seen here http://home.att.net/~synthsource/ens76/vco2.htm We're also
>going to be building the expo converter from the same circuit (it's the one I
>understand the most). But at this point, we need tempcos, they mention tellabs
>q81 which is a 2k 3500ppm/degrees celcius (some say 3300ppm/...) precision
>resistor. Which one is more precise, 3500 or 3300?
>
>Anybody has few (5-8) for sale or knows a place to get them for less than 8$
>each?
>
>Thanks a lot
>
>Charles

         -Jim
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