Fuzz Face Ge Transistor Voltage Problem - Again

[facon]

Hey guys, I just put together a standard GE NPN Fuzz Face and I'm having a strange issue. All CBE voltages for both transistors show as 8.5V. It doesn't change when I change the value of the trimpot. It's as basic as it gets and I don't have any cold solder joints or bad connections, etc. Any experience with this? Is this a sign of bad transistors? Thanks!

[facon]

continued...

[facon]

Well, I thought I was problem free, but I can't get it to bias correctly. It doesn't sound horrible, but it doesn't sound right. I paid a premium for tested AC176 transistors, so I really hope the seller isn't pulling one over on me. I put what the seller listed as HFE and leakage. I tested HFE, but didn't verify leakage. In order to get C2 to 4.5V R2 needs to be at around 400 ohms. That doesn't seem right at all. I verified that I have the transistors in the correct order and triple checked the pinout. I have the tranny following values:

Power (battery) 8.27V

Q1 (HFE = 65, L = 17mA)
C = 1.48V
B = 1.48V
E = 4.85V

Q2 (HFE = 122, 32mA)
C = 1.35V
B = 1.48V
E = 1.34V



R1 = 33K
R2 = 8.2K
R3 = 470
R4 = 100K

Modifications include the cap values only. .1uF, .1uF and 10uF.

Can somebody take a look and offer any help on how I can get this situated?

EDIT: Maybe I'm going crazy, but I verified the HFEs when I got the trannys. I just popped them in the DMM again and the HFEs are much higher now. Q1 is 224 and Q2 is 346. This doesn't make any sense to me.

[PRR]

> All CBE voltages for both transistors show as 8.5V.

No ground.

> Q1 ...E = 4.85V

In the plan, Q1 Emitter is direct connect to ground, zero volts.

So it can't be at 4 volts.

Or else it isn't really connected to ground.

[chromesphere]

EDIT: Maybe I'm going crazy, but I verified the HFEs when I got the trannys. I just popped them in the DMM again and the HFEs are much higher now. Q1 is 224 and Q2 is 346. This doesn't make any sense to me.

Hey man.  Just a note, you cant measure hfe of a germanium transistor in a dmm.  They don't give you accurate readings.  Google "germanium transistor tester" you will see a faq page on smallbears website.  Down the bottom is a small schematic.  Build it and test them in that if you are unsure of the hfe's.

Also what PRR said.  The emitter of Q1 is connected to ground, so it should read zero.  You probably have a short somewhere on the board.

Good luck with your build
Paul

[facon]

Thank you! Trace was lifted on Q1 E.