[sdiy] Moog VCHPF pole's NPN/PNP matching

[Michael E Caloroso]

Ah - my databook is not that detailed, it only lists HFE at 10mA not below.

MC

On 4/22/14, Jay Schwichtenberg <jays at aracnet.com> wrote:
> Michael,
>
> The data sheets for the 2N3904 and 2N3906 (Fairchild & Diodes Inc
> (DMMT3904/DMMT3906)) I have show different gain characteristics for them
> below Ic = 10ma. If you look at the BC549/BC550 the curves they are really
> close. I'd be nice if the 2N parts would have a gain curve like the BC parts
> do.
>
> Jay S.
>
> -----Original Message-----
> From: Michael E Caloroso [mailto:mec.forumreader at gmail.com]
> Sent: Tuesday, April 22, 2014 6:26 PM
> To: Jay Schwichtenberg
> Cc: synth-diy
> Subject: Re: [sdiy] Moog VCHPF pole's NPN/PNP matching
>
> According to my vintage Fairchild databook, the 2N3096 (PNP) has the
> same hfe spec (aka gain curve) as 2N3094 (NPN)
>
> You are correct about matching NPNs to NPNs for the HPF.
>
> MC
>
>> I don't think you have to match the PNPs and NPNs gain wise. Think you
>> just
>> have to match NPNs to NPNs and PNPs to PNPs. 2N3904s and 2N3906s don't
>> have
>> complementary gain curves so that will be hard to do anyways.
>
>