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Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 14 Oct 2010, 20:39
by IvIark
jrod wrote:The 308B's I got from gordelux were all low gain around 50's hfe. The 402's are really cool, though. And they are cheap!
Sorry, I've just checked back. It was gordelux that a few people had less than impressive results with their 308Bs, and I got some 320B and 322A from him, not the 308B's. It was Orpheus_2005 that I got mine from, and although the lowest gain were about 56hfe, there was a pretty even spread up to around 90hFE. Not ideal for the FF second transistor (that's where the GT402s come in), but I must admit I still really like the sound with 2 x 308Bs at around 80hfe.

What were your 308B's physically like? I seem to remember some people getting painted grey ones and some bare metal, some with dots (in a variety of colours) and some without dot.

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 14 Oct 2010, 20:47
by DrNomis
Yep,I am sure that those are Germanium transistors,I used my multimeter set to diode test,and I used it to measure the Base-Emitter voltage,and it was .220 Volts,a typical Vbe reading for Ge Transistors,Sinner.... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 14 Oct 2010, 20:57
by DrNomis
Also,when I put them in my multimeter's Hfe meter socket,the gain varies alot when the transistor is heated or cooled down,I tried spraying them with freezer spray,the current gain dropped quickly,and when I allowed the transistor to heat up due to the ambient temperature,the Hfe crept up.... :)


so I am thoroughly convinced that they are Germanium transistors... :)


The polarity is PNP.... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 14 Oct 2010, 20:58
by fuzzmax
Buy with confidence on culturejam's site, I'm in Canada and I got my stuff like 3-4 days after I ordered stuff. very fast shipping and easy to get in touch with over the forums like ilovefuzz.com

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 14 Oct 2010, 21:14
by DrNomis
I set myself up an account at his website.... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 05:44
by DrNomis
bencoles ยป Yesterday, 21:49
Dr Nomis
Tried to PM you but says im blocked. I'll send you a few AC128's and sure ive got a few different types of PNP's around spare too!




That's odd,I did get your PM's though...hmmmmmm...... :)


Hey is there someone in freestompboxes.org,that I can talk to to get this issue with PM's getting blocked sorted out?..... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 05:54
by sinner
DrNomis wrote:

1850-0062 7226

doh :whappen: mine are 900201-81E 323, sorry to course confusion

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 10:20
by DrNomis
That's okay Sinner,it can happen easily enough mate.... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 14:16
by jrod
IvIark wrote:What were your 308B's physically like? I seem to remember some people getting painted grey ones and some bare metal, some with dots (in a variety of colours) and some without dot.
I do believe they are bare metal with either a red or grey dot. I also bought some black ones that measure a little higher around 60's hfe. I will say that all of them are very consistent in their measurements and very low leakage.

BTW, I also bought some of those tiny GT109's and they sound great in a Fuzz Face. The only other circuit I have tried them in was a Tone Bender MKII and they did not work at all. I tried many different combos and just couldn't get them to bias.

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 14:38
by DrNomis
When I had two of my 2N2048 Ge transistors in my Fuzz Face build,all the circuit voltages looked correct,I could set the biasing on the second transistor to get 4.5Volts on it's collector,I had a look at the distortion produced on my scope,it looked like a square wave to me,increasing or decreasing the signal level feeding into it seemed to affect the waveform symetry a bit,but when I fed the signal from my guitar(neck single coil pickup),the guitars signal level didn't have much affect on waveform symetry,when I tried the pedal through an amp,I got a fuzzy kind of sound but not that much sustain out of it,Q1 Hfe was about 89,Q2 Hfe was 100,it sounded a bit one-dimensional to me,what should my Fuzz Face be sounding like with good Ge transistors?,I'm suspecting the transistors I used,hence the reason why I'm after some hopefully better sounding ones.... :)


Could it be that those 2N2048 transistors had too much leakage?.... :)


The output Capacitor is a 630V 100n Greencap,I tried the recommended 10n but it was too trebly.... :)

Re: Any Way Of Getting Hold Of Some Good NKT275's

Posted: 15 Oct 2010, 14:40
by DrNomis
Oh and I noticed that the biasing would drift a bit too.... :)