Road Rage update?

[shawnee]

How about a slight modification to the road rage to allow for -18v and a place for a negative voltage regulator? It would be great to have more than -9v on the negative side.

[juansolo]

Also a road rage + would be awesome where you could add stages to get more voltage (and tap off them to get voltages inbetween). Well it'd be handy for me anyhow

[shawnee]

Yeah that would be cool too.

[jubal81]

Also a road rage + would be awesome where you could add stages to get more voltage (and tap off them to get voltages inbetween). Well it'd be handy for me anyhow

+1

[madbean]

This is the best we could do and still have it fit in a 1590B. So, you have the option of -9 through (approx) 40v, and regulated voltage via an LM317. The "switch" was added so you could use it for submini heaters (which would only need 9v input AFAIK) or from the final 40v stage.

It's still pretty big when you consider jack, switches and the actual fx pcb.

[jimmybjj]

Wow, great layout. So compact and neatly arranged.

[nzCdog]

Very nice...

[juansolo]

Very nice indeed. Though best not to drive heaters from the charge pumped section as they usually require quite a bit of current. Better if you can reg the input voltage down to something they'll take. Usually 6v if you're driving it with 9. Funilly enough, we've just built this exact thing on vero. It barely fits in the enclosure! So this would be absolutely ideal for us. Nice one Mr B.

[madbean]

Very nice indeed. Though best not to drive heaters from the charge pumped section as they usually require quite a bit of current. Better if you can reg the input voltage down to something they'll take. Usually 6v if you're driving it with 9. Funilly enough, we've just built this exact thing on vero. It barely fits in the enclosure! So this would be absolutely ideal for us. Nice one Mr B.

That's kinda what I thought. If an LT1054 is used for the pump, it might be enough but under load but the efficiency starts to drop with all that pumped up voltage. However, this could also be used to power higher voltage, non-tube fx so I think the option of having the regulator running off the input or the final stage gives you the best of both. Or, maybe include another link to run the regulator off the 18v spot for higher current output.  

[shawnee]

Awesome layout Brian. I'm still trying to get -18v though.
I built this on perf and it worked great (even with a TC1044 and 1N4001's I got +16v/-16v loaded down with a boneyard cranked up). So would a LT1054 work better even though my TC1044 is working fine?
http://www.4thlevelmedia.com/smallpics/Plexituna_PartsLayout.jpg
I thought that this little power supply (outlined in dotted pink in the layout) would be awesome if it had a place for positive and negative voltage regulators.  At first I thought that it may be able to be done on a road rage with minor add/changes but that may not be the case. After I really took the time to compare the two, they are quite a bit different. I guess the posibilities are endless. You could add the LM317 for variable voltages or make a string of voltage regulators to have taps for 5, 9, 12, 15, 18 positive and negative.

I found that using one charge pump is less noisy than stringing two together to get +/-12v so I am putting this into a Boneyard.  I'm going to run either +/-12v or +/-15v. I am still playing with it to see which sounds better to me. For lower gain stuff the higher volatge is incredible but at the highest gain settings, the touch of compression you get with a little less voltage smooths things out a bit. Either is a big improvement over +/-9v and is worth the effort in my opinion.

[madbean]

Initially I had drawn it up using two charge pumps to produce the double negative voltage. But, what you are suggesting might be the way to go in terms of space. I can try and shoehorn that in to the current layout.

I'm still undecided on how to evolve this. I plan on keep the current RR as it is, because I want to be able to offer a small PCB for simple 18v or regulated application that fits easily in a 1590B. The expanded power supply makes a lot of sense too, but the question is how best to meet the needs of everyone. Maybe it would be better to tap off the design I have so far at around 33v, add the negative doubler, and then do a third power supply geared specifically towards the submini projects I want to do (i.e. high voltage). Smallbear has a really nice 12v transformer that could be used in the submini PS. For mini amps this might be ideal since you can just plug it in...no adaptor. At the same time, there is a certain risk on my part in making a project available that deals with mains. People could hurt themselves

Another thought on the above design is to expand it to a 125B layout and then just include the I/O stuff too (switch, jacks, dc, etc).

So, I'm kinda stuck on what to do.

[jimmybjj]

I don't know if it is even feasible and certainly beyond me, but what about multipurpose board. I was thinking a multilayer but single sided layout. Layout the more complicated board on the top side and then using the existing component holes to create another single sided layout on the other side. Or even like some of the current more commercial builders and use dual purpose layout dependent on component choice.

[juansolo]

Another thought on the above design is to expand it to a 125B layout and then just include the I/O stuff too (switch, jacks, dc, etc).

So, I'm kinda stuck on what to do.

For me the greatest flexibility would be to have the 40v (with stage taps) and the reg adjustable to the front of the circuit. Negative (-9v) voltage on there could be interesting for increasing the headroom on buffers, though I'm not sure I'd really use it as I can just run a tap from the first stage anyhow. Though saying that, if I could, I probably would.

Indeed this is what we're using as our current boobtube psu:



As it's kinda a general purpose power board, I'd be less bothered about board mounted sockets and the like. Also I think starting to go the transformer route could be dodgy liability-wise. I'd stay away from the mains stuff.

Yeah and defo keep the current road rage as is, bloody useful little board that. I use loads of them.

[shawnee]

Initially I had drawn it up using two charge pumps to produce the double negative voltage. But, what you are suggesting might be the way to go in terms of space. I can try and shoehorn that in to the current layout.

I'm still undecided on how to evolve this. I plan on keep the current RR as it is, because I want to be able to offer a small PCB for simple 18v or regulated application that fits easily in a 1590B. The expanded power supply makes a lot of sense too, but the question is how best to meet the needs of everyone. Maybe it would be better to tap off the design I have so far at around 33v, add the negative doubler, and then do a third power supply geared specifically towards the submini projects I want to do (i.e. high voltage). Smallbear has a really nice 12v transformer that could be used in the submini PS. For mini amps this might be ideal since you can just plug it in...no adaptor. At the same time, there is a certain risk on my part in making a project available that deals with mains. People could hurt themselves

Another thought on the above design is to expand it to a 125B layout and then just include the I/O stuff too (switch, jacks, dc, etc).

So, I'm kinda stuck on what to do.

I agree that the Road Rage should stay like it is. I made the +/-18v board on perf that I posted a layout for and it worked fine. I really want it to be small like the road rage is. I thought that a fabbed board would be much quicker to build and smaller than a perf vesrion. (It just needs a couple of places for regulators though). I think the higher voltage project would have to be another animal all together so I'm voting for:
1. keep current road rage as is since the layout is so different from the +/-18v layout.
2. add a Bipolar Rage to the lineup (+/-18v with places for atleast one positive and one negative regulator).
3. build a larger higher voltage DC supply that would meet needs not addressed by the two small boards.

[jubal81]

My dream board would be the RR and relay switching included on the 'all-in-one' idea.

Basically, a board with mounted jacks, taps for various common voltages (9, -9, 15, -15, 18, etc.) and a relay so attaching a simple, momentary spst stomp only takes two wires.

Heck, with this in a pedal, you could easily just swap out other boards for other effects.

There could also be a high-voltage version using SMPS for tube pedals. Rick Holt's design for the submini firefly could be pretty tiny since it doesn't take many parts.