Question/Help--Ge Transistors

A place for Do it Yourself projects

Moderator: Moderators

Question/Help--Ge Transistors

Postby Sweet T » Thu Sep 25, 2008 3:03 pm

So, I got ahold of a couple of 2n1304 transistors. How do I test them with a DMM?
Sweet T
 
Posts: 16
Joined: Tue Aug 12, 2008 10:22 am

Re: Question/Help--Ge Transistors

Postby Corksniffer » Fri Sep 26, 2008 1:20 am

Sweet T wrote:So, I got ahold of a couple of 2n1304 transistors. How do I test them with a DMM?


Does your DMM have transistor testing contacts? Youll see little holes with PNP and NPN as options.
Corksniffer
 
Posts: 61
Joined: Sat Sep 13, 2008 4:10 pm

Re: Question/Help--Ge Transistors

Postby Sweet T » Fri Sep 26, 2008 8:48 am

Nope, it doesn't. I didn't know if you could just use your normal leads/probes for this.
Sweet T
 
Posts: 16
Joined: Tue Aug 12, 2008 10:22 am

Re: Question/Help--Ge Transistors

Postby Corksniffer » Fri Sep 26, 2008 12:10 pm

Sweet T wrote:Nope, it doesn't. I didn't know if you could just use your normal leads/probes for this.


Not to test them for hFE which is the normal test. You can just socket them on your PCB and see if they work that way.
Corksniffer
 
Posts: 61
Joined: Sat Sep 13, 2008 4:10 pm

Re: Question/Help--Ge Transistors

Postby noelgrassy » Thu Oct 02, 2008 12:03 pm

The 2N1304's I have are all above 40hFE > 50hFE. I imagine there aren't many leakage
issues since the Ge NPN xistors were the top of their game at time of manufacture.

YMMV 8)
Power Chords don't contain a third, so the maj&min qualities are not present. Heavy distortion adds harmonic content, and only perfect intervals have enough consonance to be clearly articulated at high distortion levels_DFunk
User avatar
noelgrassy
 
Posts: 39
Joined: Thu Aug 28, 2008 4:25 am
Location: Vaccuum Tube Valley

Re: Question/Help--Ge Transistors

Postby BJF » Thu Oct 02, 2008 4:14 pm

Hi,

About the NPN Germanium transistors suggested for this project further explained in this thread
viewtopic.php?f=10&t=1101&st=0&sk=t&sd=a&start=10

When using germanium transistors in this circuit either just one or two, change R2 in this schematic to 2K0 Ohms for increased gain.
Use 47K Ohm with higher gain silicon transistors or if you'd like to have wider sread on the potentiometer dial of low distortion sounds.

In BJF Folk Fuzzes I'd use a BC550C low noise, high hfe for T1 for lower noise and higher gain and then T1 gives stability and gain while T2 that would use a 2N1304 or similar gives most of the carachter of the sound.

A simple transistor tester can be built, but with the transistor suggested and in this circuit, there will be no specific need- this is because firstly there are dc feedback systems that keep the circuit working with a very wide range of transistors and also maximum AC gain is not utilized, which makes it possible to use a wider variety of transistors without circuit havocing.

Higher gain fuzz using the same sets of parts:

For those that have more than two pcb's on hand: it is possible to cascade two pcb's using the same layout of three controls, while gain on first in line pcb may need to be preset fairly low and EQ can be preset too if wanted.

Have fun
BJ
User avatar
BJF
 
Posts: 522
Joined: Tue Feb 27, 2007 4:43 am
Location: Stockholm
Guitars:: Les Pauls, V with P-90's and humbuckers, strats,tele duo-jet and expanding; pick ups mostly Lundgren or BJF/ Lundgren
Danelectro Barython
amps: MP CS-40, MP101, Hiwatt Custom 200, Hiwatt Custom 100, VOX AC15
Fender Blues De Ville, Fender Super Reverb, Marshall 5150 through various speakers
pedals: 42


Return to Folk Forum (DIY projects)

Who is online

Users browsing this forum: No registered users and 0 guests

cron