Problem with breadboarding

[bluebunny]

I assumed the unbroken blue and red lines that run along the power rails were meant to indicate as much.

Me too.  It would be easy enough to do a very quick continuity test to confirm.

[frogman]

I've been typing on my phone so just to avoid any confusion this is what you need to do to make sure all your V+ and GND rails are connected.

Jumpers like in the following picture.

After testing, continuity does exist between the gaps marked in this picture, on this breadboard. The slightly larger gaps in the very middle are not connected though.I ended up re-doong the whole thing and getting sound by orienting the volume and gain pots different, still not how the circuit should sound though.

[GibsonGM]

On every board I've ever seen, for 20 years, there is continuity between the rows of 5.  On a FEW boards (they did NOT have blue and red lines along the busses, they were all white and were hard to work with), the continuity stops in the middle, and you'd need ONE jumper for each row to continue it.   Yours might be that way too, of course.  They're made to use those rows for power, and thus have continuity for at least part of their length, by definition.


What we have here is the need to go back to simplicity, I think.  It should be small work to determine if there's continuity, and it looks like Frogman just did that.    Next is to see if you read about 9V referenced to ground in the places you should, like outboard of any collector resistors.   It might have been easier to try a few more BASIC projects before something this complicated, ha ha!   But we can carry on....

Earlier, you had said something about V+ and ground being connected together - now THAT wouldn't be a good thing!!  I'm thinking it must've been a typo, or you'd have no places to measure any 9V.     Everywhere that needs 9V must have it, and everywhere that needs to go to ground also must be well-connected.    No ifs ands or butts, they have to.       And NO resistors can cross (touch leads) each other! That's an old way to get shorts, has caused many problems over the years ;o)    Sometimes you can get things working by moving the resistors/caps lightly with a pencil eraser...

[duck_arse]

in my humble opinion, and from years of doing, it is far better to have components with their leads as short as they need to be to reach a row of holes; sticking straight out the bottom, unbent, of caps, bend square at the ends, or stand on end for resistors, etc. nothing more than six or seven holes between. THEN, link with single-core wire, let it and it's insulation do the hard work and the flying and the reaching.

and move the parts closer together, close like in the circuit diagram.

I've been wrong before, though.

[pappasmurfsharem]

On every board I've ever seen, for 20 years, there is continuity between the rows of 5.  On a FEW boards (they did NOT have blue and red lines along the busses, they were all white and were hard to work with), the continuity stops in the middle, and you'd need ONE jumper for each row to continue it.   Yours might be that way too, of course.  They're made to use those rows for power, and thus have continuity for at least part of their length, by definition.

What's the design purpose of Sectioning them off into Sets of 5 if there is already continuity? why not just Straight rows.

[frogman]

On every board I've ever seen, for 20 years, there is continuity between the rows of 5.  On a FEW boards (they did NOT have blue and red lines along the busses, they were all white and were hard to work with), the continuity stops in the middle, and you'd need ONE jumper for each row to continue it.   Yours might be that way too, of course.  They're made to use those rows for power, and thus have continuity for at least part of their length, by definition.


What we have here is the need to go back to simplicity, I think.  It should be small work to determine if there's continuity, and it looks like Frogman just did that.    Next is to see if you read about 9V referenced to ground in the places you should, like outboard of any collector resistors.   It might have been easier to try a few more BASIC projects before something this complicated, ha ha!   But we can carry on....

Earlier, you had said something about V+ and ground being connected together - now THAT wouldn't be a good thing!!  I'm thinking it must've been a typo, or you'd have no places to measure any 9V.     Everywhere that needs 9V must have it, and everywhere that needs to go to ground also must be well-connected.    No ifs ands or butts, they have to.       And NO resistors can cross (touch leads) each other! That's an old way to get shorts, has caused many problems over the years ;o)    Sometimes you can get things working by moving the resistors/caps lightly with a pencil eraser...

I am not sure what you mean by '9V referenced to ground'. From the schematic, some things go to ground and others to 9V. Excuse my ignorance, but aren't they nothing more than reference points?

Also in the schematic, there is an electrolytic capacitor linking 9V and ground together?

You may be on to something though... I' m sure I could benefit from bearing in mind that the ground and 9v must be completely separate.

[MaxPower]

What Gibson means is that you take voltage readings using ground as the reference point (ground/negative lead of the multimeter on ground, the positive lead to the place you want to check the voltage). Check that you are getting the voltage readings you expect where you expect them. All too often newbies (we've all done it) make the mistake of taking readings using a different reference point (and not specifying). Then chaos ensues.

The capacitor going from +9V to ground is meant to short unwanted ac to ground. If it's between stages it's probably there to prevent possible oscillation (or is that just an op amp issue?). Or it could be there to filter the power supply (from dc ripple?). At least that's my understanding of its purpose(s).

[frogman]

Ended up getting it earlier today. It really helped to designate separate sides of the board for 9V and ground, cutting the leads shorter also helped me spot misplaced stuff... Will definitely be doing it this way in the future!

[GibsonGM]

What Gibson means is that you take voltage readings using ground as the reference point (ground/negative lead of the multimeter on ground, the positive lead to the place you want to check the voltage). Check that you are getting the voltage readings you expect where you expect them. All too often newbies (we've all done it) make the mistake of taking readings using a different reference point (and not specifying). Then chaos ensues.

The capacitor going from +9V to ground is meant to short unwanted ac to ground. If it's between stages it's probably there to prevent possible oscillation (or is that just an op amp issue?). Or it could be there to filter the power supply (from dc ripple?). At least that's my understanding of its purpose(s).

+1, Max, and you did hit on the right concept, Frog - it's about 'references'.     

Another kind of 'reference' would be if you measured the voltage drop of a diode IN CIRCUIT, with your probes on either side of it. You might read "1.87" on either side of an LED ("across the LED"), for instance.   That would be referenced 'cathode to anode'.     If you measured with one probe on ground, you could read "8.2 on one side (anode), 6.33 on the other (cathode)" in this example.     So, we just say 'referenced to ground' in those situations (most ALL) where you want to read "the voltage on the... <insert part name here>".    Keeps it simple - I am overcomplicating the description here!

Max also is correct, the cap between 9V and ground is a filter, or reservoir, cap. It acts kinda like a little 'battery' if your power supply gets dodgey/ripply, and also helps to "decouple" the power supply (good topic for searching/reading).       Yes, 9V and gnd ARE entirely separate FOR DC.

For AC signals, they are one and the same (the filter cap becomes a virtual 'short' to an AC signal), but I'll leave you to achieve greatness with the boarding before we get into THAT area, ha ha, not really important yet...glad it's working for you now, keep on throwing circuits together and soon it will all make sense!