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Title: Rangemaster transistor BIAS, help needed !!
Post by: Nocturno on March 25, 2004, 03:23:27 PM

Hello,

I am building a Rangemaster clone . The transistor i want to use is an PNP germanium ASY25/3 with a hfe of 95 .
Before this i used a AC 128 with hfe of 70 , but it turned out to be too leaky to use .

Now my problem is , that i can't reach the -7V on the collector . Turning the BIAS pots , like mentioned in the instructions on the GEO page, has just a little effekt on the collector. The voltage stays roughly at -8,5V even with the trimpots at max .

Is there any value i can tweak, to get it to -7V ????

Stefan

Title: Rangemaster transistor BIAS, help needed !!
Post by: saros141 on March 25, 2004, 03:26:06 PM

Are the leads of the transistor touching? Are they in the right socket holes? Sounds like a short.

Title: Rangemaster transistor BIAS, help needed !!
Post by: Nocturno on March 26, 2004, 09:19:46 AM

Ok, i solved the problem myself , i plugged in the transistor wrong way :oops:

Now it's working and sounds killer with 7,4 V on collector and 9,3 V battery charge .

Thanks anyway

Steve

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DIY Stompboxes => Building your own stompbox => Topic started by: Nocturno on March 25, 2004, 03:23:27 PM