# Small Bear Germanium Setups Question



## joelorigo (Sep 15, 2021)

I was able too pick up a 3 knob tone bender setup from Small Bear a few weeks ago:








						Transistor Set - 3-Knob Tone Bender NPN All American
					

Small Bear Electronics DIY Parts




					smallbear-electronics.mybigcommerce.com
				




I have a Kilimanjaro that I have been working on and off on for a while and none of the small amount of transistors I have worked. They said these are good for a tone bender V1 based circuit so I am going to try them.

Anyway, they included a "Ge diode, tested in the circuit." What is this for?


----------



## fig (Sep 15, 2021)

That's D1. It goes from the base of Q3 to ground (I believe).


----------



## Bricksnbeatles (Sep 15, 2021)

The Tonebender mk 3 circuit has a germanium diode from the base to ground to deal with temperature stability


----------



## fig (Sep 15, 2021)

Bricksnbeatles said:


> The Tonebender mk 3 circuit has a germanium diode from the collector to ground to deal with temperature stability


The collector? Groovy.
Nope, base. 😁


----------



## Bricksnbeatles (Sep 15, 2021)

fig said:


> The collector? Groovy.


Whoops. Edited. 
I’m not fully awake today 😂


----------



## joelorigo (Sep 15, 2021)

I see. So in the Kilimanjaro circuit, it is not needed? Stick with the 1N5817 which is the only diode in the circuit?


----------



## fig (Sep 15, 2021)

That is correct. The 5817 is reverse polarity protection.

You can save the Ge diode and use it in a clipping stage.


----------



## joelorigo (Sep 15, 2021)

Thank you!


----------



## joelorigo (Sep 15, 2021)

Actually, one more question. How do I tell the pinout of these transistors? I pasted the wrong link above. Here is the correct one:









						Transistor Set - 3-Knob Tone Bender PNP Generic
					

Small Bear Electronics DIY Parts




					smallbear-electronics.mybigcommerce.com
				




Here's a pic of one of them. No identifying marks that I see.


----------



## Coda (Sep 15, 2021)

joelorigo said:


> Actually, one more question. How do I tell the pinout of these transistors? I pasted the wrong link above. Here is the correct one:
> 
> 
> 
> ...


The leg under the tab (to the right in your pick) should be the emitter. Base would be in the middle and collector on the left. I feel like SB would have told you if it wasn’t the standard layout. Best bet is to socket.


----------



## joelorigo (Sep 15, 2021)

Coda said:


> The leg under the tab (to the right in your pick) should be the emitter. Base would be in the middle and collector on the left. I feel like SB would have told you if it wasn’t the standard layout. Best bet is to socket.


Thanks. I am using sockets.


----------



## Chuck D. Bones (Sep 16, 2021)

If you are buying germanium, you would benefit greatly from owning a transistor tester.  Besides measuring electrical parameters, it can be used to confirm the pinout.


----------



## andare (Sep 16, 2021)

Chuck D. Bones said:


> If you are buying germanium, you would benefit greatly from owning a transistor tester.  Besides measuring electrical parameters, it can be used to confirm the pinout.


Thinking of buying one of those cheap testers. From what I've seen, they're just as reliable as a Peak.


----------



## SillyOctpuss (Sep 16, 2021)

andare said:


> Thinking of buying one of those cheap testers. From what I've seen, they're just as reliable as a Peak.


They work just fine but they're not reliable at all from my experience.  I've had 3 die in 6 months.  Thankfully they're all under warranty but doesn't exactly inspire confidence for when the warranty runs out.  I'm just going to buy a peak tbh.


----------



## fig (Sep 16, 2021)

SillyOctpuss said:


> They work just fine but they're not reliable at all from my experience.  I've had 3 die in 6 months.  Thankfully they're all under warranty but doesn't exactly inspire confidence for when the warranty runs out.  I'm just going to buy a peak tbh.


Were you able to determine what caused the failures? I've never looked at one beyond the pics posted here. Now I'm curious...do they have a MP?


----------



## Big Monk (Sep 16, 2021)

andare said:


> Thinking of buying one of those cheap testers. From what I've seen, they're just as reliable as a Peak.



I've used mine daily for close to 8 months now. Solid as a rock.


----------



## SillyOctpuss (Sep 16, 2021)

fig said:


> Were you able to determine what caused the failures? I've never looked at one beyond the pics posted here. Now I'm curious...do they have a MP?


No Tim I haven't.  In each case the unit has powered off in the middle of a test and not come back on again.  I did read a thread talking about desoldering the battery and reconnecting to 'reset it'. That worked once on one of mine.  The others came with a connector for the battery rather than a soldered connection.  I just returned them rather than taking them apart any further.


----------



## fig (Sep 16, 2021)

I suppose they are assembled at various locations with varying practices and QC tolerances.


----------



## SillyOctpuss (Sep 16, 2021)

fig said:


> I suppose they are assembled at various locations with varying practices and QC tolerances.


Yeah probably.  I know other people are happy with theirs but I've been burned too many times now and will just go for a dca55 this time.


----------



## Chuck D. Bones (Sep 16, 2021)

Mine just passed the 2 year mark and is still running strong, knock on wood.  The only problem I've had with it is sometimes I have to wipe off the pads on the board that are for testing SMDs because humidity and dust will accumulate over time and cause leakage.


----------



## Chuck D. Bones (Sep 16, 2021)

fig said:


> I suppose they are assembled at various locations with varying practices and QC tolerances.


Like everything other consumer electronic device.


----------



## andare (Sep 16, 2021)

There are a bunch of them that look very similar.

Which one do you guys use?


----------



## Chuck D. Bones (Sep 16, 2021)

The seller from whom I procured mine is no longer on eBay, or has changed names.


----------



## andare (Sep 18, 2021)

Someone told me the LCR-T1 tester measures leakage but I haven't been able to confirm that from this video 




Edit: I see that it reads ICEO and ICES which Google tells me are leakage. I think I'll buy this one.


----------



## SillyOctpuss (Sep 18, 2021)

Yes that's one of the ones I had @andare it definitely measures leakage


----------



## Big Monk (Sep 18, 2021)

andare said:


> Someone told me the LCR-T1 tester measures leakage but I haven't been able to confirm that from this video
> 
> 
> 
> ...



Iceo is the leakage value.


----------

