AN749?

[jorgen.bergfors at idg.se]

Hi transistor gurus.

My Doepfer PMS VCOs use a transistor marked AN749 to discharge the timing cap. 
This works fine, but if I try any other transistor the sawthooth wave vill not 
be linear at medium to lower frequencies. Increasing the base resistor (to 1M 
from 680k) improves linearity somewhat, but not enough. Even the AN749 gives 
reduced linearity at very low frequencies, but it is still much better. 
Anyone know what's so special about the AN749? I have a couple of VCO boards 
that are unpopulated, so I need the components, but the AN749 is nowhere to be 
found. Well, at least Farnell and a couple of others don't stock it.

/Jorgen