[sdiy] Which transistors for synth circuits?

Oren Leavitt obl64 at ix.netcom.com
Fri Jan 7 00:58:15 CET 2022


On 1/6/22 4:59 PM, Terry Bowman via Synth-diy wrote:
> This is a very interesting thread. I'm reminded of a similar discussion we had years ago about how component specs had silently improved over the decades. In particular, someone tested a variety of LM3046s. As time went by Q1 and Q2 consistently became better matched. IIRC, chips of recent manufacture were better than the MIL specs on the datasheet.
>
>
>> On Dec 30, 2021, at 6:08 PM, Oren Leavitt via Synth-diy<synth-diy at synth-diy.org>  wrote:
>>
>> MPSA42 (NPN) and MPSA92 (PNP) - high voltage 300V.
>
> What, no MJE340 (300V NPN)? The MPSA42 is fine for an ИН-13 bar-graph tube but can't handle the higher current of an ИН-9...

Actually I do have MJE340 and MJE350 (its 300V PNP compliment) .

>
> Oh wait, this is SDIY not the Nixie tube group. Sorry.  8D
>
>
> In all seriousness, what do you need 300V transistors for (especially PNP)? Driving a VFD or plasma display?
I've used the 300V devices in pro audio power amplifiers that can easily 
have 200+ volts between the rails. Yes, Nixie tubes, too. Hmmnnnn, 
perhaps maybe a Dekatron step sequencer sometime ;)
>   Or perhaps something like this:
>
> http://m.bareille.free.fr/vu-in13/vumeter_in13.htm
>
>
> Terry Bowman, KA4HJH
> "The Mac Doctor”
>
> (The notorious thread hijacker)
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Usemarketplace at synth-diy.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20220106/07b3ac97/attachment.htm>


More information about the Synth-diy mailing list