my 2n5089's measure around 600hFE!!!

[cedric]

aren't they supposed to be between 70-120 ?

[Peter Snowberg]

5089s are high gain.

From the Fairchild datasheet: http://www.fairchildsemi.com/ds/2N/2N5089.pdf
hFE DC Current Gain

IC = 100 µA, VCE = 5.0 V
5088 gain 300-900
5089 gain 400-1200

IC = 1.0 mA, VCE = 5.0 V
5088 gain 350 or higher
5089 gain 450 or higher

IC = 10 mA, VCE = 5.0 V
5088 gain 350 or higher
5089 gain 450 or higher

Take care,
-Peter

[cedric]

wow.. didn't know that!

how will it work in a fuzzface then?

[RDV]

Quite well @ Q2. Use something lower gain @ Q1 like 2N4401, or 2N2222, or 2N3904 & you'll be fine. My fave is 2N4401 @ Q1 & 2N5809 @ Q2.

Regards

RDV

[Paul Marossy]

I have had some measure over 800. Almost unbelieveable.

[smoguzbenjamin]

Trannies with a gain of 1000... think about it man :mrgreen:

[cedric]

Trannies with a gain of 1000... think about it man :mrgreen:

wouldn't that "just" gain the volume by smogzillions?

[smoguzbenjamin]

It would create screaming distortion with just 2 trannies.....

[Paul Marossy]

Screaming distortion with only one trannie. Check out Joe Davisson's "Easy Drive". One transistor wonder!

[smoguzbenjamin]

Wow... cool... Now to find a tranny that works for us with a gain of 1000

[Fret Wire]

Quite well @ Q2. Use something lower gain @ Q1 like 2N4401, or 2N2222, or 2N3904 & you'll be fine. My fave is 2N4401 @ Q1 & 2N5809 @ Q2.

Regards

RDV

A 3904 & a 5089 will work in the classic Si fuzz circuit? Using the standard bias voltages? I'll have to try that. Kinda gettin' tired of hunting down BC108/109's.

[MarkB]

I think an MPSA18 has a gain of about 1000..
screeeeeaaam
"-)

[puretube]

Kinda gettin' tired of hunting down BC108/109's.

those were the european working horses for over 30 years...
for a decade the only ones to buy in local stores..
prob. 100`s of millions floating around...

[Gus]

Read the sections about transistors in the ART OF ELECTRONICS.  Look at the max gain advaible in a circuit with a set voltage.  Remember it is not just hfe, look at changes in hfe vs Ic graphs.  Some transistors have a gain that changes alot with changes in Ic others are more stable hfe vs Ic.

Don't get hung up in part numbers or hfe  to much use your ears, take notes, read about how transistors work.  there is a science to to sound IMO.

FWIW the 3 tran and other Si circuits I build are design around not having to worry about hfe for the circuit to work.

[Mark Hammer]

Also note the wide variation in hfe within the same transistor type, as indicated in Pete S's posting.

[David]

I built a Muffer and put a 5089 in it.  It SCREAMS!

Looking forward to a Rocket with three of 'em!   :twisted:  :twisted: :twisted:

[WGTP]

How about the MPSA013 Darlingtons.  Off the scale.   :shock:

[puretube]

...if too way off: piggiback`em to bring down the gain again; lol.