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Thread

BC547 substitution.

2005-01-02 by hitchindave

Hi All.

Has anyone successfully tried substituting 2N3904s for
BC547s? Apart from the pinout being reversed, the specs look
very similar, and I have lots of them.

They would be going in a CGS22 master divider, and I guess
they're being used there as switches, so the difference in spec.
is hopefully not critical.

Cheers,

Dave K

Re: BC547 substitution.

2005-01-02 by Richard Brewster

Sure, you can use 2N3904 for the buffers in the master divider. Be
aware that the Emitter and Collector pinouts are *reversed* from the BC547!

I generally use BC549B for my general purpose NPN transistors. But I
also used up my stock of 2N3904. I found that the main difference is in
gain, with the 3904s having lower gain. For switching uses the gain
doesn't make a significant difference. The output is either on or off.

-Richard Brewster

hitchindave wrote:

Show quoted textHide quoted text

>Hi All.
>
>Has anyone successfully tried substituting 2N3904s for
>BC547s? Apart from the pinout being reversed, the specs look
>very similar, and I have lots of them.
>
>They would be going in a CGS22 master divider, and I guess
>they're being used there as switches, so the difference in spec.
>is hopefully not critical.
>
>Cheers,
>
>Dave K
>
>
>
>
>
>
>
>See the following URLS for the CGS Modular Synth home page:
>Main: http://www.cgs.synth.net/
>Secondary: http://otherunicorn.0catch.com/synth/
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
>

Re: BC547 substitution.

2005-01-02 by sasami@hotkey.net.au

>Has anyone successfully tried substituting 2N3904s for
>BC547s?

No problems at all. Tbe BC547 is a very generic transistor. As I use them,
there are many transistors that will work in their place.

Ken

_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: BC547 substitution.

2005-01-03 by hitchindave

Well, that's a pretty comprehensive yes! The master divider will
now hopefully soon be up and running, and if I can suss it out,
with a Blacet midi-sync IC front end to lock it up to the world of
MIDI.

Thanks to you all for the replies.

All the best for the new year,

Dave

Cgs synth

BC547 substitution.

BC547 substitution.

Re: BC547 substitution.

Re: BC547 substitution.

Re: BC547 substitution.

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