Author Topic: Which transistor is Q1  (Read 1153 times)

jball85

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Which transistor is Q1
« on: November 26, 2013, 08:48:56 PM »
I was under the assumption that the top transistor in this layout was Q1, but now I think the bottom is Q1. Can anyone confirm this?

http://tagboardeffects.blogspot.com/2013/03/analogman-sunface-nkt275.html

pryde

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Re: Which transistor is Q1
« Reply #1 on: November 26, 2013, 09:09:05 PM »
pulling up a schematic (assuming it is correct) has Q2 emitter connected to the fuzz pot.

So in that layout the top transistor is Q1. bottom is Q2

jball85

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Re: Which transistor is Q1
« Reply #2 on: November 26, 2013, 10:03:33 PM »
I can only get a reading of -4.5v on the top transistor's collector, it's value changes in conjuction with the sundial pot.

Bret608

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Re: Which transistor is Q1
« Reply #3 on: November 27, 2013, 09:23:35 AM »
I don't know enough about anything beyond a basic Fuzz Face to say for sure (and I certainly don't want to contradict you, Pryde!  :)), but in my experience, the folks at Tagboard usually do a Fuzz Face Q2 or Tonebender Q3 as an ECB pinout, and that will be connected to whatever bias trimmer is there. On the layout you used, the top transistor has that ECB arrangement. So if that's the one where you're getting bias changes, it could be your Q2. If I had time I would check this against the Sunface schem for you. I think if you can find one, crosswalking it with the Tagboard layout will be the best way to put it to rest.

Also, how is it sounding? I did a hybrid ge/si Fuzz Face using their basic NPN FF layout and it sounds awesome.

twin1965

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Re: Which transistor is Q1
« Reply #4 on: November 27, 2013, 11:18:56 AM »
Q1 is the bottom transistor. Input goes to the 50K trimmer. This then goes to the 1uF cap and then to the base of Q1.

jball85

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Re: Which transistor is Q1
« Reply #5 on: November 27, 2013, 04:40:15 PM »
thanks everybody. I have 80 hfe and 100 hfe oc47s. With the transistors backwards it didnt sound that bad. Im about to switch them, I'll report back with results.

jball85

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Re: Which transistor is Q1
« Reply #6 on: November 27, 2013, 05:31:58 PM »
sounds much tighter with less noise now.  ;D