NEW DALLAS RANGEMASTER (Verified) LAYOUT

[sgRED]

^{New layout i made and posted, just to be helpful to anyone building this kind of circuits out there. Also if anyone has some suggestions and questions, of course they're very welcome.}  

[gcme93]

Thanks for the layout sgRed, good to see another Vero fan like myself


I've had a look over it and a couple of bits seem to need adjusting:

- As a minor point, the transistor pins are labelled upside down: C is at the top, E at the bottom

- R1 and R2 are labelled the wrong way around (R2 is 470K from base to 9V, R1 is 68K from base to ground)

- Check where R3 is going to: I think you meant it to go from that bottom transistor pin to ground

- Finally, R4 isn't on the schematic, so its probably worth adding it on to the schematic or checking whether its needed or not - unfortunately I'm not the kinda man to know what it does, maybe you could let me know?

Sorry to hit you with so many negatives on this, I'm pretty new to designing vero layouts too and it can be a bit of a jigsaw. Ultimately you're very nearly there, so tweak those few things, check it on a breadboard and then hit us with Revision 1!


George

[midwayfair]

I've had a look over it and a couple of bits seem to need adjusting:
- Finally, R4 isn't on the schematic, so its probably worth adding it on to the schematic or checking whether its needed or not - unfortunately I'm not the kinda man to know what it does, maybe you could let me know?

Pull-down resistor.

[gcme93]

Yepp that makes sense. Thanks for the info

[sgRED]

Sorry Sorry Sorry my good people!!!! I just found out i used a totally wrong picture to upload, because, this vero i posted is an old one from 5 days ago. What i meant, is to post a picture below, that i made and that has all the corrections. First of all, I soldered everything last night and it works,   but `gcme93 and others` i still need your opinion on this one, because the upper one is totally wrong. Here's the second one:

And yes! Pulldown resistor don't need to be there as it is only needed in a NPN version of this schematic (as the matter of fact, it needs two 1,5M or 1M just to remove clicks and pops when using with 3PDT true bypass setup, in a real stompbox format. PNP circuit doesn't work with that 1,5M in place, so i deleted it frome the vero, and `desoldered` it in the real life for this PNP version, as I've tryed it), and now it looks pretty good concerning the resistor positions regarding the George's advices, and sound good also

[gcme93]

This one is very nearly there! I've realised your error is just that you have the ground and 9V labelled the wrong way around! Very easily done.

Therefore, you need to change:

1. Those labels of 'ground' and '9V'

2. The polarity of C3 and C4 to the other way around

3. The protection diode polarity so that it's facing the other way.

On the schematic also, the battery is the wrong way around, and the two electrolytic capacitors (C3 and C4) are the wrong way around. This was confusing me quite a bit!


One final point: is the protection diode needed?

Having that diode there causes a voltage drop of about 0.7V or so, immediately reducing the 9V to 8.3V. Having looked at this datasheet: http://alltransistors.com/transistor.php?transistor=21204 it seems that the transistor isn't going to get damaged, plus the caps shouldn't explode at 9V if they're rated at 16V or more

[R.G.]

One final point: is the protection diode needed?

One could debate that for a while, but electro caps are damaged by reverse current flow, and while they do withstand some minor reversal, it's small - a volt or so depending on the manufacturing. So a reversed battery would not make the caps explode, but it could well make them leaky and then unable to support their normal voltage. Depends on how much current flows when.

Old germaniums were about equal in collector-base breakdown and emitter-base breakdown, but as germaniums got better at amplifying, their base-emitter diffusions got more different and able to withstand smaller and smaller reverse voltages, just like silicon did.

It's probably not a 'sudden death' situation like with some opamps if this circuit gets reversed, if the reverse doesn't last long. Touching a battery to the wrong terminals on the clip isn't a disaster. But leaving it connected to a 9V power adapter for while might start killing things while one pondered why it didn't make any sound this time.

Whether or not the protection diode is needed, it's really necessary not to have parts on the board that don't appear in the schematic. That's confusing to any reader as well.

[sgRED]

This one is very nearly there! I've realised your error is just that you have the ground and 9V labelled the wrong way around! Very easily done.

Therefore, you need to change:

1. Those labels of 'ground' and '9V'

2. The polarity of C3 and C4 to the other way around

3. The protection diode polarity so that it's facing the other way.

On the schematic also, the battery is the wrong way around, and the two electrolytic capacitors (C3 and C4) are the wrong way around. This was confusing me quite a bit!


One final point: is the protection diode needed?

Having that diode there causes a voltage drop of about 0.7V or so, immediately reducing the 9V to 8.3V. Having looked at this datasheet: http://alltransistors.com/transistor.php?transistor=21204 it seems that the transistor isn't going to get damaged, plus the caps shouldn't explode at 9V if they're rated at 16V or more

OK, How about now??? And one point, i am checking the schematics and i can't find the "polarity" mistake??? Explain further please, i just cannot see it, and i'm checking it against the upper schematic on the pic (see also: http://fuzzcentral.ssguitar.com/rangemaster.php), and it seems OK!!!!!!!!!!!!??? The corrected image is below:

[sgRED]

One final point: is the protection diode needed?

One could debate that for a while, but electro caps are damaged by reverse current flow, and while they do withstand some minor reversal, it's small - a volt or so depending on the manufacturing. So a reversed battery would not make the caps explode, but it could well make them leaky and then unable to support their normal voltage. Depends on how much current flows when.

Old germaniums were about equal in collector-base breakdown and emitter-base breakdown, but as germaniums got better at amplifying, their base-emitter diffusions got more different and able to withstand smaller and smaller reverse voltages, just like silicon did.

It's probably not a 'sudden death' situation like with some opamps if this circuit gets reversed, if the reverse doesn't last long. Touching a battery to the wrong terminals on the clip isn't a disaster. But leaving it connected to a 9V power adapter for while might start killing things while one pondered why it didn't make any sound this time.

Whether or not the protection diode is needed, it's really necessary not to have parts on the board that don't appear in the schematic. That's confusing to any reader as well.

I deleted the diode as you suggested!

[gcme93]

Sorry Sorry Sorry my good people!!!! I just found out i used a totally wrong picture to upload, because, this vero i posted is an old one from 5 days ago. What i meant, is to post a picture below, that i made and that has all the corrections. First of all, I soldered everything last night and it works,   but `gcme93 and others` i still need your opinion on this one, because the upper one is totally wrong. Here's the second one:

And yes! Pulldown resistor don't need to be there as it is only needed in a NPN version of this schematic (as the matter of fact, it needs two 1,5M or 1M just to remove clicks and pops when using with 3PDT true bypass setup, in a real stompbox format. PNP circuit doesn't work with that 1,5M in place, so i deleted it frome the vero, and `desoldered` it in the real life for this PNP version, as I've tryed it), and now it looks pretty good concerning the resistor positions regarding the George's advices, and sound good also

I am so so sorry about this, I've been a complete idiot. I totally overlooked that you're working with a PNP transistor, so this version I've quoted was actually completely correct, all the polarities are the right way around for positive ground.

This has taught me absolutely loads about double checking against the schematics and reasoning with myself as much as anything. I'm very sorry for having wasted your time on this when you'd made a good layout already!

As for the diode, test it out yourself if you can hear any difference between using it or not. If not, then why not add it in anyway? Engineers love extra safety if its easy!

Very sorry again, thank you for putting up with me!

[sgRED]

This has taught me absolutely loads about double checking against the schematics and reasoning with myself as much as anything. I'm very sorry for having wasted your time on this when you'd made a good layout already!
As for the diode, test it out yourself if you can hear any difference between using it or not. If not, then why not add it in anyway? Engineers love extra safety if its easy!
Very sorry again, thank you for putting up with me!

No sir. You are not an idiot. Because that was the same mistake I have done. It almost took me to build it when I just remembered that AC128 transistors that I had laying around were PNP. Then i had to change everything, so then i finished soldering and discovered that a pulldown resistor ain't doing enything but killing my gain and volume on this thing. So i removed it instantly and it played perfectly. But you're right! Always check everything! I was caught with on something iv'e been doing and missed the headline of the schematic saying: NPN verified version !!! So it happens to everyone Now i know that everything is correct! Tonight i'm about to remove that diode and see if some changes occur!?

[gcme93]

Thanks for being understanding

I mean if you like the sound of it with the diode, there's definitely no harm in keeping it in? I definitely need to breadboard this circuit as soon as possible. Sounds pretty sweet from clips I've heard

[sgRED]

Here are the demos:

and there is a demo in the instrumental mix also:

[sgRED]

 

AND OF COURSE, A "VERIFIED" STAMP ON THE PICTURE FOR THOSE WHOM MIGHT DOUBT WHEN THEY'RE BUILDING IT!
HAPPY PLAYIN'