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Tractor beam, high pitched sound when effect 0ff or on?

Started by Spenzerleehorton, October 15, 2018, 02:56:53 PM

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Spenzerleehorton

Hi All,

Building tractor beam and bit confused of what zener to use as it just says zener?

Any ideas?

m-Kresol

it's a 4.3 V zener diode. Go to page 8 of the build doc for some infos.
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
My build docs and tutorials

Spenzerleehorton

Sorry I think I've not explained correctly, it's on the switching board marked D2 and just says zener and says refer to chart?

What chart?

madbean

The chart is in the doc specifically for the switching board. Different VFE projects use different value Zener diodes on the switching board. In the case of the Tractor Beam, it's a 16v Zener. The chart is on page 7 of the Switching Board build doc. In reality, you could use a 12v, or 18v or none at all. It's only to prevent over-voltage getting to the circuit but if you are careful about always plugging in 9v then it's no big deal on the Tractor Beam.

brucer

That would be the Zener chart on page 7 of the switching board BOM (see http://www.madbeanpedals.com/projects/VFE/VFE_SwitchingBoard_v2.pdf).  It calls for a 16V zener at D2 on the switching board if you're building a Tractor Beam (i.e, a 1N4745A like this one in the MB cart for the v2 switching board: https://www.mouser.ca/ProductDetail/512-1N4745A). 

Spenzerleehorton

Ah perfect thank you, I didn't find that very clear.
Will give it another look.

Spenzerleehorton

I'm still gathering parts for this build along with a green bean and a death claw.
Totally revamping all my pedals, I've built an mxr flanger, tremolo, phase 90, big muff and a Snow White env filter.
Might also build the coral reef as I like the chorus on the whammy pedal but would like to try a different version.

Spenzerleehorton

Completed parts yesterday but unfortunately had IC wrong way round so fried it!!!
Ordered a new one, voltages look good, switch pcb all works fine, can hear that control and switches work but no signal when in bypass?

Spenzerleehorton

seems i'm prone to problems on every build!!! i do tend to learn quite a bit though, which im totally happy about.

anyway my build hasnt gone well, in bypass im not getting signal through pedal first of all

effect on sounds distorted, with mix control to left hardly any signal but distorted, mix control to right is just a total mess but can hear guitar signal but no effect.

here are voltages

OPA2134
1- 4.2mv
2- 4.2mv
3- 0v
4- -7.21v
5- 0v
6- 0v
7- varies
8- 8.04v

LM358
1- varies
2- varies
3- varies
4- -7.50v
5- varies
6- varies
7- varies
8- 8.05v

TLE2074
1- varies
2- 4.1mv
3- varies
4- 8.06v
5- varies
6- 4.2mv
7- varies
8- varies
9- varies
10- varies
11- -7.49v
12- varies
13- varies
14- -6.29v

2N5952
G- varies
S- 0.2mv
D- varies

any help would be fantastic as i really love this pedal!!!!!



Spenzerleehorton

Anyone have any ideas of how I can get this puppy working please?

Spenzerleehorton

I have used wires to connect the jack sockets from J1 and alt for input and J2 and alt for output?
Is this ok or do I need to connect it differently?

Spenzerleehorton

#11
I need a new switching board pcb!!!, i've had a tough time fault finding this pedal but i put in the relay the wrong way round then tried taking it out!!
needless to say the pcb hasn't survived!!

I have managed to take everything off the pcb now and i think the parts are ok.

How do i go about ordering a new switching board pcb?

regards

Spence.

Spenzerleehorton

Right I have the new switching boards and I've installed and it does switch but cuts the signal out!?
If I leave the effect on and then disconnect the power lead I then see the normal sign, if I have the effect off and then disconnect power it cuts the signal?
Waveform is all over the show when effect is engaged but need to get switching pcb working correctly first so any help is much appreciated.

Regards

Spence.

madbean


Spenzerleehorton

here's a few pictures, any help is much appreciated.