[sdiy] LM394 vs. MAT02 vs. ?

[Dana Scott]

Hi,
The transistors in the 4014 were Vbe matched. The circuit that there was a 
recent link to ( oldcrow?) would be adequate. In the later days of 2600 
production we used 2n5087 and 2n5089 for the tz581 and tz81 . We had to slip 
a tiny piece of Teflon tubing over a couple leads and bend the leads around 
because  the pinout was different ( ebc vs ecb IIRC). Matched pairs were 
usually clipped or glued together. Some later 4075 VCF's( 1979 or 1980 ) 
were not clipped. In that case the selection process yielded enough 
transistors in a single matching bin to build an entire production kit( 100 
VCF's) The pairs were color coded because joining them would obscure the 
markings.
-Dana

----- Original Message ----- >
> In a message dated 11/5/04 11:58:51 AM, turbo at writes:
>
> << The ARP PNP/NPN  pairs were never electrically matched at all. Just 
> take
> two
>
> transistors and stick them together. >>
>
> Hello Dana,
>
> As always, thank you for the valuable ARP insights.  With all the
> misinformation, half-truths, and speculation that floats around the 
> Internet, t's really
> great to be able to get the real skinny from someone who was actually 
> there.
> I am now wondering about the transistors used in the 4014 ring modulator
> submodules.  Was there any matching going on in there, or did you guys 
> simply use
> transistors straight out of the bag?  The schematic I have (originally 
> from
> Joachim Verghese's great ARPtech website, now located at
> http://www.oldcrows.net/arptech/modmain.htm) depicts several pairs of 
> transistors with a colored
> circle drawn around the pair, presumably either to indicate matched 
> pairs -- or
> does it mean that these pairs are to be physically touching each other, 
> like the
> ones you were mentioning with the brass clips?
>
> I have always loved the way that particular ring mod sounds, and I'd like 
> to
> clone a couple of them.  I know that those original Zetex TZ-81 (NPN) and
> TZ-581 (PNP) transistors are pretty much impossible to find these days, so 
> which
> currently available transistors might you recommend as substiutes?
>
> Michael Bacich