[sdiy] Tempcos a NoGo

[George Welsh]

I recently inquired to Precision Resistor about 2k tempcos. I got this
response.

"10 pcs.@$7.36 ea.  Stock and would be able to ship out within 2 days after
receipt of order.
 We only have the 1K's on the web order page but we ocassionally have the
2K's readily available. If we had to manufacture these 10 pcs., then lead
time would be approximately 5 weeks as a ship date"

So it looks like they are still made. I ordered some from Elby in Aus,
because I didn't need that many. So the ones mentioned above are still
available.

George W


> > Are they a direct replacement, other than mechanical concerns, for the
> > Q81? If so, am I simply missing something obvious? Wouldn't it be
> > trivial to make a tiny carrier out of a piece of standard copper clad
> > perfboard? I'm talking about the kind that has a number of holes
> > connected together so you can mimic solderless breadboard layouts.
> > Take a small strip with fourholes connected together, xacto away the
> > middle trace, solder the tempco accross the gap, use the outside holes
> > to mount leads.
>
> Well, they arnt "direct" replacement.  The tempco is 3300PPM and they only
> seem to be stocked in 1k, but even so, 3300PPM is "darn close" ( whats
> ideal, 3350?  I forget. ) and the things are dirt cheap.

Is it reasonable then, if one wanted to build something that employed
1k tempcos to use the panasonics and if one wasn't happy with the
performance to simply remove it and replace it with the proper unit?
And I presume that there's nothing particularly "wrong" about my
cheapo mounting method?

> Took me a while but I found the part numbers in an old order :
> P1.0KCDTR-ND = Full reel of 5000, $730  15cents each...
> P1.0KCDCT-ND = Cut Tape, 10 for $5.52 with substantial quantity breaks.

Great, thanks, I'll order some of those.

> > Can you be specific on fairly inexpensive?
>
> A group buy of a few hundred gets the price into the $2-$3 range.  Last 1k
> KRLs I got were $1.80 and the 2k's were $2.50 or so.  I dont remember the
> exact quantity but I think we got 300 1k's and 100 2k's, but dont hold me
to
> that.

That seems fairly reasonable. Most schematics I recall seeing use the
1k devices. Are the 2k devices fairly common also? Where are they most
often used?

Thanks,
Daryl
_______________________________________________
Synth-diy mailing list
Synth-diy at dropmix.xs4all.nl
http://dropmix.xs4all.nl/mailman/listinfo/synth-diy


-- 
No virus found in this incoming message.
Checked by AVG Free Edition. 
Version: 7.5.472 / Virus Database: 269.8.11/838 - Release Date: 6/7/2007
2:21 PM