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Circuit

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sniper007

New Member
Hi!

I try to draw scheme for this circuit. I'm not sure what is first and what second transistor (NPN, PNP) ?

Note: Power supplay is -15V

Regards,


7480-photo037v.jpg
 
Last edited:

Hero999

Banned
They're both PNP transistors.

It's nothing complicated, just an emitter follower connected to a common emitter amplifier.

The circuit is really old, they might even be germanium transistors; what are their part numbers?

What are the tolerance of the resistors?

The 82.7k is certainly just 82k.

The 10.7k is probably 10k but it might be 11k.

The 1.6k resistor is 1.5k if it's 10% tolerance or 1.6k if it's 5%.

Because it's such an old circuit, the resistors are probably all 10% tolerance.
 

sniper007

New Member
Thanks Hero999 for quick replay. so is this correct ?

7481-19900522.jpg
 

Hero999

Banned
That's it.

If you want to build it you'll need to replace the resistor values you measured with standard values as I mentioned above.

With the component values shown the gain will be 13.8 assuming a gain of 100 for Q2.
 
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