Capacitors multimeter question

Started by bifbangpow, August 05, 2015, 07:19:28 PM

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smallbearelec

The pics are a big help. I am pretty sure that the input jack is mis-wired, which would prevent the circuit from being powered correctly. Please go to this article:

http://www.diystompboxes.com/beginnerboost/ and look at Figure 29

That pic identifies tip, ring and sleeve of a Switchcraft #12B or similar jack. Now look at the off-board wiring drawing at guitarpcb:

http://www.guitarpcb.com/PDF%20Files/Fuzzy%20Bee_v2.pdf

Make sure that you are clear about which contacts of the jack are T R and S and where they go, and I think you will see that you need to re-wire. I dunno if that's the only issue, but see if it cures the problem.


duck_arse

I second the bear's answer. the yellow wire on the yellow/blue socket looks to be wired to the switch. if you use a single colour wire for all your ground connections, different to your hot/signal/tips wire colours, it will help avoid confusion. I can't tell which wire is connected to ground at in and out on your board.

when I say the bypass, yes, I mean the bypass switch/footswitch/stomp switch. and when I say work the switch, I mean toggle/flip/push/changeover/work it, so it changes state (off to on, vice versie).

for measuring the resistances about the place, unplug the plugpak/wallwart/external supply. unplug the battery, won't hurt either. when you short the probes together on any ohms range, it should read steady "0.00" or very low. but rock steady.

your board looks ok otherwise, the externals is where most errors get made.
don't make me draw another line.

bifbangpow

Quote from: duck_arse on August 19, 2015, 10:52:41 AM
I second the bear's answer. the yellow wire on the yellow/blue socket looks to be wired to the switch. if you use a single colour wire for all your ground connections, different to your hot/signal/tips wire colours, it will help avoid confusion. I can't tell which wire is connected to ground at in and out on your board.

when I say the bypass, yes, I mean the bypass switch/footswitch/stomp switch. and when I say work the switch, I mean toggle/flip/push/changeover/work it, so it changes state (off to on, vice versie).

for measuring the resistances about the place, unplug the plugpak/wallwart/external supply. unplug the battery, won't hurt either. when you short the probes together on any ohms range, it should read steady "0.00" or very low. but rock steady.

your board looks ok otherwise, the externals is where most errors get made.

with the battery unplugged, shorting the two meter probes together definitely does not give me 0.0 on my meter reading.  it gives me a lfuctuating crazy read. could my meter be broken?
Keep on keepn on.

bifbangpow

#23
ok so it works!!!

I miswired the input jack by switching the tip & the ring lugs. and I did the same with the output jacks. The confusion was that in the guitarpcb.com diagram the tip is the left prong and the ring is the right prong, but on my input jack it's opposite.  I didn't know that was possible. Now I understand that tips/rings/sleeves are not determined by their lateral position but rather by the rung on the pot they are connected to.  LEARNING. 

But now there is a NEW PROBLEM. All the pots are backwards, in the sense that the level gets higher when turned counter clockwise instead of clockwise.  But I couldn't have wired them wrong because they are on-board components.  was I supposed to put the actual pots in on the opposite side of the board than everything else? It seems like then i would have to do that for the led as well... and... i dont know. Now i'm very confused.

Keep on keepn on.

smallbearelec

Quote from: bifbangpow on August 19, 2015, 03:03:24 PM
ok so it works!!!

CONGRATULATIONS! Now you've learned a basic: You can do 99% right, but the 1% that's not right is fatal. That's how it is with this stuff. See additional comments below.

Quote from: bifbangpow on August 19, 2015, 03:03:24 PM
was I supposed to put the actual pots in on the opposite side of the board than everything else?

In this case, Yes. The build doc isn't quite specific enough, IMO. Take a look at the schematic. The side of the sustain pot that is connected to the + side of cap C2 is the Clockwise (CW) side. If a regular pot is wired to the top side, the CW contact is wired by hand to C2. For the right connection to happen with a board-mounted pot, the pot has to be on the bottom side. Unsolder the Sustain pot (you will want solder wick for this)

http://smallbear-electronics.mybigcommerce.com/de-soldering-braid/

and re-mount on the bottom. Same for the other pots. BTW your soldering looks pretty good, which is Very important.

Suggestion: Getting more comfortable with troubleshooting means learning a bit about how and why things work the way they do so that you have a better idea of where to look for problems. Please give a read to my Beginner Project tutorials on this site and consider learning to breadboard. Then build at least one pedal on perfboard and go through the process of learning to wire by hand. Lest I be misunderstood, I am not in any way putting down guitarpcb, GGG, Tonepad and other sites that offer ready-to-solder (RTS) PCBs; a number of these are my customers. The stuff I discuss in the tutorials is In Addition To, and not in place of, the information that the RTS board sites provide. Ideally, I think every beginner should go the breadboard/hand-build route first to build skills and confidence and then do kits. But starting higher on the learning curve is also fine, as you are finding out. Happy Construction!

Regards
SD


duck_arse

nice work on the getting to work. if this is your meter:



and you have the black lead plugged to the bottom (COM) jack, the red lead plugged to the middle (VohmmA) socket, and the 200 ohm (I can't find the omegas on my keyboard) switch setting, shorting the leads should read 0. if it doesn't, pull the red lead out, and poke the black probe into the VmA jack. that should read 0. [if anybody knows, how do those sockets work? are the contacts completely shrouded when no plug inserted?]

do the same with the red lead plugged in, remove the black. if either test shows other than 0, you have a bad lead. if both read bad, it's something else, or two bad leads.
don't make me draw another line.

bifbangpow

#26
Quote from: smallbearelec on August 19, 2015, 04:41:47 PM
....BTW your soldering looks pretty good, which is Very important.

Suggestion: Getting more comfortable with troubleshooting means learning a bit about how and why things work the way they do so that you have a better idea of where to look for problems. Please give a read to my Beginner Project tutorials on this site and consider learning to breadboard. Then build at least one pedal on perfboard and go through the process of learning to wire by hand. Lest I be misunderstood, I am not in any way putting down guitarpcb, GGG, Tonepad and other sites that offer ready-to-solder (RTS) PCBs; a number of these are my customers. The stuff I discuss in the tutorials is In Addition To, and not in place of, the information that the RTS board sites provide. Ideally, I think every beginner should go the breadboard/hand-build route first to build skills and confidence and then do kits. But starting higher on the learning curve is also fine, as you are finding out. Happy Construction!

Regards
SD

Yeah I only use kits sometimes.  I actually have etched my own pcbs all ready.  I etched my own maestro sr 1 fuzz pedal a couple times, and a fox tone as well.  But you're right, I jumped right into the deep end without knowing some of the basics.  I've done a lot of reading on the subject, but not having a real person to ask questions to means sometimes I misunderstand something.  Going back to a breadboard seems a little to simple to me, but if you still think I should go back and try a breadboard... i guess i could do that. Do you think I need that?
Keep on keepn on.

bifbangpow

Quote from: duck_arse on August 20, 2015, 11:03:09 AM
nice work on the getting to work. if this is your meter:



and you have the black lead plugged to the bottom (COM) jack, the red lead plugged to the middle (VohmmA) socket, and the 200 ohm (I can't find the omegas on my keyboard) switch setting, shorting the leads should read 0. if it doesn't, pull the red lead out, and poke the black probe into the VmA jack. that should read 0. [if anybody knows, how do those sockets work? are the contacts completely shrouded when no plug inserted?]

do the same with the red lead plugged in, remove the black. if either test shows other than 0, you have a bad lead. if both read bad, it's something else, or two bad leads.


Yeah, i definitely do not get zero.  When putting the black lead into the Vma I get fluctuating numbers. Same when i do the opposite with the red lead. 
I guess I should get new leads?
Keep on keepn on.

smallbearelec

Quote from: bifbangpow on August 21, 2015, 01:21:52 PM
Going back to a breadboard seems a little to simple to me, but if you still think I should go back and try a breadboard... i guess i could do that. Do you think I need that?

Maybe not at the very basic level in the beginner tutorial. But the ability to read a schematic and translate the wiring in a drawing to connections of physical components is an essential basic for serious work. Maybe you want to breadboard something a little more complex, like a Big Muff.

Curiosity: Does your multimeter have a scale with a diode symbol (like the one just above ON in the photo)? That's the continuity function. It should give a continuous BEEP when the leads are shorted. I ask, because learning to use your meter and interpreting what it's telling you are also part of the basics.

duck_arse

biffbang - can you set yr meter to "DCV 20" range, and measure the voltage of a battery, any battery. then turn the battery around, and test again. do you get a reading that settles quickly to a sensible number? and do you get a negative reading in the same manner? do you just get wandering nonsense?
don't make me draw another line.