Baja Trembulator schematic, board layout and circuit board

bajaman · Post by **bajaman** » 12 Aug 2007, 03:18

Great work Steve! I can verify fellas that this is one very awesome sounding trem. Very smooth.

and very low noise too.

Post by **modman** » 16 Aug 2007, 00:56

Ok, in between crazy moments I could djangle this baby a bit.
Damn Baja, very fine smooth and incredibly silent. Maybe that's just me having tested too many distortion circuits.

Initially, I got no sound at all, probed it got nothing across the first IC and no supply voltage on any of the chips, so of course the diode was put in the wrong way. Lately that's more statisfying even than getting it to work immediately: intelligent debugging. Maybe I'm learning after all.

BTW, use the small square LDR and a 3mm square LED and ductaped them skillfully into complete darkness. Worked just fine. When I tested the bare led at 5V the LDR only gave me 1k-2k max. What should be the approximate max resistance?

haven't said a word about the design.... maybe it's a bit.... let me know. Thanks again for this one. We should look for more projects. This really is a valuable build. Personally tremelo building wouldn't occur to me, having a super sweet tremelo in my amp.

hear ya
mm

bajaman · Post by **bajaman** » 16 Aug 2007, 07:45

Hi Modman - glad to see you got it working

haven't said a word about the design.... maybe it's a bit.... let me know

Sorry - me not understand - feel free to share it and your thoughts with all - even though it is derived from the DEMETER TREMULATOR, the oscillator section IS my original design inspired by the NATIONAL SEMICONDUCTORS 1971 design brief.
This is Freestompboxes - so Everyone is free to build, sell or generally just enjoy it

( I do not want any payments or royalties - it is my gift to the World's musicians)
bajaman - ageing hippie

Post by **modman** » 16 Aug 2007, 08:03

Baja, I sent you this by mail your crazy hippie (i think ..er...)

Trembulatin' leaves?

bajaman · Post by **bajaman** » 16 Aug 2007, 08:11

Hi Modman
The silver fern looks good - don't forget the pulsing LED though.
Very nice work

bajaman

Post by **modman** » 16 Aug 2007, 12:23

No, no , will drill that after I see the arrangement and space in the box, also need 9V DC supply and will try to keep it in a small box. When it's boxed up I might do some decent clips despite the fact that I don't believe in clips

But still

Didn't know it was a fern, supposed a plant, but didn't read far enough for that, I thought it could also be a line of warriors on a hill at sundown. Is that taking it too far, probably

We should forget the mods you mentioned, maybe some toggle switches wouldn't be bad, should try out how far this baby goes. Sorry but what is the function of the 10k trimmer exactly?

it's not led indicator led intensity?

Baja, will not be selling this, it's just a trial build for a friend who's tired of his Boss. Was going to build him a booster for 49EUR but ended up giving it for free for his birthday. I'm one crappy salesman..

bajaman wrote:Slow as you would ever need - if you change the 50k lin pot for a 500k lin you will get very sloooooow speeeed

bajaman wrote:ALSO if you want to get it running ridiculously fast lower or short out the 10k resistor in series with the rate (speed) pot.

You may like to put a 20k trim pot ( replace 18k) in the feedback loop of the LF351 ( or TL071) etc., to adjust the optocoupler light intensity also.

Post by **modman** » 31 Aug 2007, 01:19

Put up some pictures bulding the Baja Trembulator.

bajaman · Post by **bajaman** » 31 Aug 2007, 01:29

It looks better than my one

thanks for the pictures
bajaman

Danch · Post by **Danch** » 23 Oct 2007, 12:06

Just noticed that in schematic there is 2x22nf and on board layout they are marked as 2x220nf?

bajaman · Post by **bajaman** » 23 Oct 2007, 19:04

Thanks Danch - 220n is the correct value. I will correct the schematic values - good spotting
bajaman

Post by **modman** » 04 Nov 2007, 11:39

Anybody fancy a Baja Trembulator clip for breakfast? Two zipped mp3s one a high, other at lower speed. How silent is that tremolo? Any noiseless tremolo will still take on the noise of your amp, so blame the noise in the amp.

Great box!

sure hope this link works, we'll have better hosting for this kind of stuff sooner than you can say trembulator.

OrionManMatt · Post by **OrionManMatt** » 31 Dec 2007, 20:57

How difficult would it be to add a "tap" function to this design? And what about adding an input for an expression pedal?

I really liked the trembulation. Also a big fan of the EA tremolo as well.

soulsonic · Post by **soulsonic** » 31 Dec 2007, 21:16

I think expression pedal control would be easy - or you could even build it into a wah case.

By "tap" do you mean "tap tempo" where you set the speed by tapping on a footswitch? I'm sure it would be possible, but it would definitely add alot to the circuit since it would require an additional "thinking" circuit with a clock and all that stuff.

OrionManMatt · Post by **OrionManMatt** » 31 Dec 2007, 22:52

soulsonic wrote:I think expression pedal control would be easy - or you could even build it into a wah case.

By "tap" do you mean "tap tempo" where you set the speed by tapping on a footswitch? I'm sure it would be possible, but it would definitely add alot to the circuit since it would require an additional "thinking" circuit with a clock and all that stuff.

Especially if you're getting some quasi-Leslie goodness out of a tremolo, having an expression pedal that can control the rate seems like a sweet little bonus. Or if you just like fiddling with knobs and doing experimental music.

And, yes, a tap tempo. My apologies for not being more clear about that. It just seems to most reasonable way to approach tempo to me. I hear studio friends of mine that just shake their heads when they want to record some bit using their tremolo and it takes longer than they would like to dial it in with the tempo of the song. Would delay circuits be the place to look for that type of "thinking" circuit, or what would be the best way to approach this?

I should record the tremolo on my Beltone AP-24 (hand-wired, PTP, 6AV6 to (2) EL84, 5AY3 TR) one of these days. It doesn't have a very large range, but it's VERY pulsating and yummy, much like this tremolo.

OrionManMatt · Post by **OrionManMatt** » 15 Jan 2008, 18:38

soulsonic wrote:I think expression pedal control would be easy - or you could even build it into a wah case.

By "tap" do you mean "tap tempo" where you set the speed by tapping on a footswitch? I'm sure it would be possible, but it would definitely add alot to the circuit since it would require an additional "thinking" circuit with a clock and all that stuff.

I completely overlooked your suggestion to build it into a wah case. Me thinks you may be onto something. Also, was there any further thought to developing the thinking circuit to add the tap tempo function to this tremolo?

vanessa · Post by **vanessa** » 28 Jan 2008, 01:34

Hey Baja, Can I get away with a 100k pot for the depth control? Not having an extra 50k What would be better 100k or 25k?

bajaman · Post by **bajaman** » 28 Jan 2008, 07:16

Hey Baja, Can I get away with a 100k pot for the depth control?

Yes should still work okay

cheers
bajaman

analogguru · Post by **analogguru** » 02 Feb 2008, 17:55

found by chance - Trembulator on youtube:

analogguru

bajaman · Post by **bajaman** » 02 Feb 2008, 19:00

Roa · Post by **Roa** » 18 Sep 2008, 22:16

Hey baja, I´m gathering info on the demeter trem and saw this topic that seem really interesting, but I have a problem as I can´t use your first link. It sends me to a different "freestompboxes" page and a message appears saying it is no longer available...

Baja Trembulator schematic, board layout and circuit board [documentation]