I have a few Bc109's & some BC109B's & I was testing them in my multimeter & the BC109's all read from 300 to 350 or abouts & the BC109's read around 550 to 675. Is this the way it suppose to work? Do the lower gain have higher readings?
Yes :D & No :cry:
Transistors often come in different packages with A, B and C markers
those BC109's are probably "A"'s "B"'s are higher gain and "C"'s highest.
I have BC549A/B/C with the same kind of hfe increases.
Marty.
I didn't understand that? What do you mean yes & no. Is a higher reading lower gain or not? They are plainly marked on the transistor what they are. When I put the BC109B in my pedal you can deffenently tell it has less gain. I meant BC109b. I was confused.
BC109 (with no letter suffix) will usually be higher gain than any of the others.
Then you get into the BC109A, BC109B and BC109C. Out of those three, the "A" will have the lowest gain and the "C" will have the highest gain. Makes it easier to pick out a specific gain range :)
Phillip
So let me get this right. BC109 is highest gain. BC109A is lowest. In other words they rank in gain from highest gain in this order. Highest to lowest=BC109, BC109C, BC109B, BC109A?
Quote from: jabezI didn't understand that? What do you mean yes & no. Is a higher reading lower gain or not? They are plainly marked on the transistor what they are. When I put the BC109 in my pedal you can deffenently tell it has less gain.
Hmm,
in your post, you've called them both "BC109's" without the "B" !!
I'm presuming that your "B" marked transistors are higher gain.
Perhaps you mean that's not the case ..... so ......
If there's no "A/B/C" marking on them its harder to tell, but the gains
will always increase through A-B-C versions
Unmarked and "higher" than the "B" marked ones ?, then you can call them "C"'s ..... making sense ??
Marty :D
Phillip has cleared it up .... thanks ! SO:
Unmarked - very high gain
A - lowest
B - medium
C - high gain
:D
Marty.
Okay I think you read that reply out of context with the first reply. So here goes again. I have a few transistors that have printed on them BC109 with out any A B or C suffix & that is what I bought them as BC109's & on my meter they read around 600 to 700. The BC109B's I have got BC109B printed on them & they read around 300 to 350 on my meter & I had the impression that BC109's with out any A, B, or C suffix were the lowest gain. So is the BC109 without any suffix is actually the highest gain or what cause I'm confused now.
I was not sure about the "unmarked" values but I trust Phillip's experience on that one totally ! :D
The rest is as per my last post, gains go up through A-> B -> C suffix's
OK?
Marty.
BC109 is ungraded, so they could actually vary anywhere in between the BC109A and the BC109C and beyond. But from the ones that I have and tested, yes, they ungraded BC109 (no letter suffix) are higher gain than my BC109B and BC109C. But since they're ungraded they may vary from lot to lot.
I don't have any BC109A to test, though, but if the grading system is consistent, then the "A" grade would be lower gain than the "B" grade.
Phillip
Yeah I understand now. I didn't see your other post when i wrote the last one I wrote MartyMart
I tell you where I got turned around is that I read in a couple topics that in a wah pedal to put the highest gain in the Q1 & the lowest in the Q2 spots. Then I read a couple topics where some people like to have a BC109 in the Q2 spot so I just naturally assumed that the BC109 was a lower gain transistor. I have a BC109B in the Q1 & a BC109 in the Q2 spot of my wah & it sounds better this away. To me anyway. Well anyway thank for clearing that up.
Quote from: jabezThen I read a couple topics where some people like to have a BC109 in the Q2 spot
Thats the first time I've heard that.
I saw it all here. Somewhere! At least that's the story I'm sticking to!