+gnd. GREEN ringer

Started by petemoore, April 17, 2014, 11:02:09 PM

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petemoore

  I feel a goofy green coming over me..lol.
IIRC the GR schematic used to have the user choice to be positive gnd. [what I'm trying to work with pnpQ1, npnQ2, PNP Q3] so I just reversed all the polar marks on the negative ground schematic I could find.
I've been troubled by a couple Q1's [Germanium] not biasing.
I started with the stock NPN -gnd. values [er...sorta close], and varied the resistors slightly and greatly to try to 'separate' the base from the emitter by more than .2V...they both follow each other or the emitter jumps from say .60v to 6.85v [using a 7.75v battery, the base follows the 'rules' with this board and came in at .62v.
I'd like to start over with a fresh board and fresh values for Q1, as my spacious board.
I've got six buxx, I'm too cheep to buy SI transistors [also I havde reasons to believe the GE's tested, work just fine. I tore apart a Pioneer reciever but still can't find a spare Si transistor that registers on my DMM's Hfe meter.
I can't find the article about biasing a GE transistor so just dogmatically raised and lowered every resistor value associated with Q1. The collector R value has been 10k, 30k and 20k, the Base to ground has been everything between 100k and 200k, Base to power rail values ranged between 100k, 220k, 440k and 540k [a couple 220k's and a 100k's] the emitter's had R values to ground ranging from 3k3 through 6k8.
HAving measured each value on the board many times, checked for erronious connections and searched the not at all cramped board by sight, and various DMM settings [voltage, resistance, continuity]...I figured I'd snitch before I ditch this one anyway.
The emitter either follows the base voltage +.2v or jumps way up to near the collector voltage.
I dunno, schematic or biasing instructions aside...I resorted to last resorts and wonder whether or not the weather matters with this one.
It was nice, sunny and not cold today though.
I know the transistors work and are probably low leakage [15ua, 39ua, 65ua if we can trust my measurements and math...lol] because the GE leakage and gain tester results were vouched for by the Fuzzface too.
Fuzzface sounds supergreat, but the Green Ringer continues to refuse to honor my best efforts.
So I pitch this entry wishing it was more complete, less scattered-brained.
This should be a simple/easy debug [compared to my experience] but has proved brick wall like in nature this time around.
So...I'd like to start over and over again hoping to bias a GE boost stage similar to what is the green ringer Q1.
Convention creates following, following creates convention.

thehallofshields

I tried a PNP Fuzz Face with an NPN Green Ringer that seemed fine (and sounded amazing) on breadboard, but ended up with fried components when I transferred it to perfboard.

http://www.diystompboxes.com/smfforum/index.php?action=printpage;topic=103822.0

Driving a Green Ringer with a Germanium Fuzz seems to a pretty common idea, since the compression, additional amplitude and general messyness of a Fuzz effect can really fill in some of the shortcomings of the original Ringer Circuit.

http://www.diystompboxes.com/smfforum/index.php?topic=96472.0

For mixing PNP and NPN, I believe I was given the suggestion to add some resistance to the + of the PNP circuit.