Show me your 1590A enclosures/pedals...

[tubelectron]

Ah, yes ! Very good & interesting, solderman !

This is the direction I would take : the tremolo circuit must be non-photocell, ultra-compact (or compactable)... And yours is ! So I will make a trial on it, of course... Thanks for the schematic link.

I have some questions about it :

This tremolo is a mix between different schematics I have found and compiled to this
one you find here. It is simple but cowers the basic needs for a tremolo. Since the C3
Cap always needs to be charged for the tremolo to start and it is charged trough the
LED I have chosen to use a dual color LED with common Cathode. This way it's
always ready for use. The LED is also flashing in LFO speed so you can always see
the dialled in Tempo.

1 - C3 is listed at 100µF, but on the schematic there is only a 100nF output cap : is it C3 ? Is there a mistake value ? I don't see any 100µF cap...

2 - It seems that one of the BF245B is a gain modulated amplifier (a kind of VCA), where the bias is varied via the 2nd BF245B which can be called as modulator, working as a variable resistor, controled by the BC547B phase shift oscillator. Is my interpretation good ?

2B - Do you mean that the led is a constant current cap loader ?

3 - Can you have a deep modulation with this kind of VCA operation ? I mean going to something approaching a "repeat percussion effect / machine gun effect" ?

4 - Do you notice modulation throb ?

5 - The schematic I was thinking about was not VCA, but a FET in modulated variable resistor, followed by a another one in level compensation amp, and of course a T-bridge or phase-shift oscillator to give the modulation. Do you experimented that principle ?

A+!

[solderman]

Ah, yes ! Very good & interesting, solderman !

This is the direction I would take : the tremolo circuit must be non-photocell, ultra-compact (or compactable)... And yours is ! So I will make a trial on it, of course... Thanks for the schematic link.

I have some questions about it :

This tremolo is a mix between different schematics I have found and compiled to this
one you find here. It is simple but cowers the basic needs for a tremolo. Since the C3
Cap always needs to be charged for the tremolo to start and it is charged trough the
LED I have chosen to use a dual color LED with common Cathode. This way it's
always ready for use. The LED is also flashing in LFO speed so you can always see
the dialled in Tempo.

1 - C3 is listed at 100µF, but on the schematic there is only a 100nF output cap : is it C3 ? Is there a mistake value ? I don't see any 100µF cap...

2 - It seems that one of the BF245B is a gain modulated amplifier (a kind of VCA), where the bias is varied via the 2nd BF245B which can be called as modulator, working as a variable resistor, controled by the BC547B phase shift oscillator. Is my interpretation good ?

2B - Do you mean that the led is a constant current cap loader ?

3 - Can you have a deep modulation with this kind of VCA operation ? I mean going to something approaching a "repeat percussion effect / machine gun effect" ?

4 - Do you notice modulation throb ?

5 - The schematic I was thinking about was not VCA, but a FET in modulated variable resistor, followed by a another one in level compensation amp, and of course a T-bridge or phase-shift oscillator to give the modulation. Do you experimented that principle ?

A+!

Me bad. I see I have goofed up in same places. This is a based on the EA tremolo at GGG and some thing I can't remember where. 

1 - C3 is listed at 100µF, but on the schematic there is only a 100nF output cap : is it C3 ? Is there a mistake value ? I don't see any 100µF cap...

A- I made a mess about the cap' s. C1=In cap and is 10nF on the chem.. I rised it to 47nf, not 470 as in the BOM. C3 is the "modulation cap holding the Q2 to switch to ground. Shem. said 1uF I raised it to 100uF.

2 - It seems that one of the BF245B is a gain modulated amplifier (a kind of VCA), where the bias is varied via the 2nd BF245B which can be called as modulator, working as a variable resistor, controled by the BC547B phase shift oscillator. Is my interpretation good ?

A- ovet the top of my head :-)

2B - Do you mean that the led is a constant current cap loader ?

A- Yes, The LED flashes in phase with the speed. If the stomp switch is used to turn off the led together with the effect (true bypass) when you turn it on again it will take about 2 seconds befor it starts to modulate the sound eg. the cap is loaded. I solved this by using a two colour LED , red is OFF and green is ON

3 - Can you have a deep modulation with this kind of VCA operation ? I mean going to something approaching a "repeat percussion effect / machine gun effect" ?


A, NO it has a modest tremolo effect. If you want some thing deeper try this.

http://www.diystompboxes.com/smfforum/index.php?topic=75372.msg613734#msg613734

Its machinegun sound and really deep and goes from really slow to super fast.



4 - Do you notice modulation throb ?
A- No

5 - The schematic I was thinking about was not VCA, but a FET in modulated variable resistor, followed by a another one in level compensation amp, and of course a T-bridge or phase-shift oscillator to give the modulation. Do you experimented that principle

A-   Same as Q2

[drhulsey]

Getting a small circuit into a small enclosure is one thing, but getting a more complicated circuit to fit is a totally different story. I haven't seen anyone discuss their thought processes regarding the modification of a circuit for getting it into a smaller enclosure. Are you thinking more about smaller components or eliminating certain components? Obviously, arranging the components is vital. It would be interesting to have someone like Anders or Daniel take a circuit and go through the thought process of decreasing its size.

[Hides-His-Eyes]

Things like 1/8W resistors and ceramic caps can help make circuits very small, as can getting dual layer PCBs fabbed (not necessarily that expensive, dorkbot charge by the square inch only)

[tubelectron]

@solderman  : thanks for your useful answer.

I was akeen to think that the principle of bias-variation VAC wasn't able to give deep tremolo effect, and here you confirm that. The resistance-variation plus recovery amp will probably do better, as I experimented it with bipolar transistors (unfortunately very difficult to compact). Nonetheless, your schematic is a base for modification.

@drhulsey :

Getting a small circuit into a small enclosure is one thing, but getting a more complicated circuit to fit is a totally different story

Absolutely. That's why It's difficult to compact my Double Tremolo in a 1590A box, even if simplified to simple tremolo :

I haven't seen anyone discuss their thought processes regarding the modification of a circuit for getting it into a smaller enclosure

IMHO, the reason why is because it is always a case-by-case basis.

Are you thinking more about smaller components or eliminating certain components?

The target being to save space, both are important. But I try first to save room by searching smaller components (where non-critical) and work the layout. Eliminating components may be sometimes critical about the performances of the circuit, so a prior test is compulsory.

Obviously, arranging the components is vital

Exactly. Here is a pic illustrating the way I needed to arrange the components on my 1590A FuzzRite, to get along with the 3PDT footswitch left in a correct position :




A+!

[drhulsey]

Thanks for the discussion!
Besides the fact that everything related to guitar uses 1/4" jacks,
would there be any down side to using 1/8" jacks between pedals or from looper to pedal?

[tubelectron]

would there be any down side to using 1/8" jacks ?

I don't think so... and it would be a way to save space. But what would stop me from that solution is the no-compatibility with the all-around guitarist equipment, and a probable lower mechanical resistance to use and abuse than the 6.35mm usual jack.

A+!

[solderman]

Hi
As Bruno mentioned it's case by case when it comes to an individual design. But to start with there is always a question to be asked, why try to fit complicated circuits in to small boxes at all?
In my case I got tiered of building another "big box" there where no challenge in it. When I first saw a 1590A here in this tread I new that this has to be developed in to something more interesting. I asked my self, where is the limit? I still don't know and we are still pushing it as I see it.
I made up the rules for my self only to use small but standard components and standard mechanics.

Then it's down to the layout. To me, making a layout is like solving the Rubic cube. Everything has to fit together and to work in the end. At the same time every thing has to go fit together in the box as well. That means that big components can't sit in the way of jack's etc.  There is no way to cheat.

This is my current personal record I believe (The John Hollis Ultra Flanger)
27 resistors
10 capacitors (3 electrolyte)
5 IC, 3 DIL8 and 2 DIL16
4 trim pot
3 normal pot
4 diodes
1 3mm LED
1 Stompswitch
1 SPDT switch
2 Jack's
1 power jack.



http://solderman.fatabur.se/f/ultraflanger%20layout.pdf

[tasos]

oh solderman!this is great!can i find all your application file's somewhere?[pcb-schem]

[blooze_man]

He shares it all on his website.

[Hides-His-Eyes]

A DPDT switch will fit between the screw holes which gains you enough space for a millenium bypass somewhere else, maybe even a relay..? More flexible.

[tasos]

He shares it all on his website.

and his site is?

[deadastronaut]

He shares it all on his website.

and his site is?

under his name.?..

[tasos]

He shares it all on his website.

and his site is?

under his name.?..

i hate when it is that easy!!! sorry!haha

[ADR]

Ohhhh, I LOVE the look of this. What paint did you use to get that blue sparkle?

White chicken head is perfect. Very retro.

A mini booster with internal tone trimmer.

[ADR]

Amazing. Love the tidy builld.

I am in the process of using your layout to make my own 1590a fuzzrite.

I will post on that thread of yours some questions I have.

Thanks for sharing!

Exactly. Here is a pic illustrating the way I needed to arrange the components on my 1590A FuzzRite, to get along with the 3PDT footswitch left in a correct position :




A+!

[tubelectron]

You're welcome, ADR.

Moreover, my 1590A FuzzRite works as expected - I am planning to makes samples with deadastronaut's tips.
My layout is OK - it's exactly what I have built. But you may note that some fuzz aficionados on the forum told me that there was a 22K missing, and it's effect seems to be very interesting, according to them - I did not tested it yet to give an additional advice. Nonetheless, built as is, it's really good already...

A+!

[Earthscum]

So, here's my (unfinished) 1590A...

I still have to debug it and do some pretty stuff to the enclosure, but I got it all stuffed tonight, so I feel accomplished, and gotta show it off a bit.

I'm calling it the Toe Jam Wah

[Taylor]

I would like to comment on that, however we're not allowed to curse on this forum.



   Wonderful job.

[Earthscum]

Damn... debug went smooth. I put my transistor in backwards, lol.

BTW (I'll post the circuit within the next day or two), the circuit I designed for this is a T-filter. I wanted to see if I could make an LDR controlled wah work off the A23 for more than a couple hours. Right now, this circuit will run from a 100uF cap for about 20 seconds before the LED goes dark, then it still amplifies for another 30 seconds or so. I think I hit my goal for a low-power consumption circuit, eh?

The LED is run from the 12V across a 100k resistor, and it still makes enough light to drop the LDR down to about 2-4k (depending on voltage). It is one of the clear bright 5mm's from Tayda. I went through about 20 to get the one that was brightest, but any of them would've worked just fine.