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Does your meter read huge? If not how are you measuring them?

Hi Matmosphere, I just found that I am supposed to use an attachment with my multimeter for transistors. I was using the positive probe on the center leg and the negative probe on each side leg to get readings for npn. I believe I read somewhere on the interwebs it was the way to determine the pins, but since my readings are different than the datasheets, I am guessing that the attachment will put them more in line.

Edit: I found my multimeter manual and found that there is a special attachment for reading transistors. So, I will find the attachment and reread my transistors. Please ignore my stupidity.

Original stupidity:
So, this probably belongs in the beginner topics.

I went through my transistors testing all of them for the Hipster build. I narrowed it down to MPSA18 @ 271 hFE, BC549 @ 280 hFE, and 2N3440 @ 340 hFE.

Since the MPSA18 was reading a reverse pinout from the others, I decided to check the datasheet to see if I was reading these correctly (b-e, giving highest hFE). When I looked at the datasheet for each of these transistors, they don't match with what I am seeing. The datasheets say that MPSA18 is a EBC, while the other 2 are CBE; this part makes sense that the one is reverse of the others, but my hFE readings are higher b->c than b->e.

I am also not seeing the hFE readings that the datasheets say I should see. MPSA18: 400-1500; BC549: 100-800; 2N3440: 40-160. 

So I am reading/ doing something wrong. Is anyone able to show me where my mistakes are?
Thanks

2N5088 and BC549 may hit hfe of 500 but you really need to get a cheapo meter that can test for silicon transistor hfe, to ne sure. You should be able to get one for $20-25. Unfortunately, transistor gains of a certain part number can be all over the place

Thanks Dan Frank.
I have a multimeter, which is how I measured the @280-320 range that I posted. I will take a look back at the 2N5088s and BC549s to see if I can find one that gets to 500.

But I imagine I will need to order a transistor and was hoping for a recommendation of transistors that range around 500-600 that would pair with something that I have on hand.

I am building MBP Violenzz and Hipster pedals. I am stuck trying to decide on transistors for these circuits. I have a small selection of NPNs and the hFE reading on all of them are ~280-320. The hipster doesn't say it needs anything specific, so I am guessing that I can just use 2 of the same transistor, the lower hFE as Q1 and the higher as Q2.
The Violenzz says that Q2 needs to be double of Q1. Does anyone know what NPN transistors would be in the 500-600 range?

Transistors I have on hand: 2n3440, 2n3904, 2n5087, 2n5088, 2n5457, bc 183 TI, BC549, MPSA18, bs170, BC407B

Usually I do this with small fragile glass housing diodes. I use a little screwdriver as guide, and wind the leads on it.

They take more space, but I'm no longer a diode destroyer!

Interesting. It was a glass housing diode. I will give it a shot.
Thanks.

Ha! funny you should mention this. I think I broke about 3 Ge diodes in 10 minutes yesterday just trying to put them into PCBS. Never had such bad luck...

Yeah, I had it soldered in but one end was higher then the other, so I decided to soften the solder and push that in a bit to even it out and it cracked.

Quite possibly the diode is dead. But they're cheap enough to replace

If you ask in the Parts Jar subforum, someone in your country might have a spare.

I have extras. I dread trying to remove the one that is in there and replacing it.
Thanks.

Hello All,
I was putting together a pedal kit and one of the diode casings cracked. I figured it should still function, but once the pedal was together, the octave part of the pedal doesn't seem to do anything except light up an LED. The octave part routed through that diode, so I was thinking that it is the problem.
http://www.generalguitargadgets.com/pdf/ggg_toct_lo_dist_f.pdf
It is the D2 diode on that wiring diagram. Would a cracked diode casing result in no effect from the second footswitch (Sw2)?
Thanks!

IME, delays, filters, modulation effects, digital... these are what generate Mutable's Level Zero troubleshooting.

Overdrives and fuzzes are good for developing your troubleshooting chops, along with some research into what these transittor and oh-pamps do

Not sure what "Mutable's Level Zero troubleshooting" is, but I have been doing some reading on "these transittor and oh-pamps". Hopefully, I will start to understand how the circuits shape the sound.

Sounds like you have some decent chops if you've come this far.  I think the hardest parts of putting a project together is:

• sourcing parts
• troubleshooting if something doesn't work, or doesn't work properly

I am looking into buying an assortment of pieces to have on hand for future projects.
I didn't have any troubleshooting on the pedal, a little on the pickups and switch. IN a way I am looking to troubleshoot to understand deeper, but if I never have to troubleshoot, isn't that like winning the lottery.?

A number of things make this site a lot easier (and I have no skin in the game, I've just been here so long it's second nature):

• really good support from the forum (lots of smart people to help you)
• really good documentation, including a description of the circuit, it's history, potential pitfalls, and enough information that you can follow how/why the board does what it does
• links to help with part sourcing
• drill guides are spot on

Sounds great, especially "enough information that you can follow how/why the board does what it does".

That said, what do you like?  I can vividly remember my first visit here (around the time the wheel was invented I believe) and being blown away with the scope of projects available.  I'd steer clear of analog delays and modulation for a first Bean project, only because these are rather expensive in parts.  Complexity is mind over matter but when you're shelling out a lot of coin for expensive chips you want to know that you have a solid track record.

There a quite a few projects here, so I am trying to narrow down the next one to tackle. Also something to fill out my pedalboard some more, though duplicates that aren't duplicates isn't a horrible thing. I am considering a chorus, phase, or a wah.

Thanks all for advice and guidance.

Thanks!

I have just recently tried my hand at building pedals. My first pedal was the ross compressor kit from general guitar gadgets: http://www.generalguitargadgets.com/effects-projects/compression/ross-compressor/

I have also built an AB switch after that and put new pots, pickups, switch in a guitar before.

What I am looking to know is if anyone could advise on the madbean scale noob -> zeus the compressor would be rated. I didn't have any difficulty putting the kit together and I am looking to challenge myself to the next level.

Thanks