News:

Forum may be experiencing issues.

Main Menu
Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - JackSkellington

#31
General Questions / Re: Dr. Boogie in the 2020
September 04, 2021, 12:59:21 AM
Thanks.
My Dr. Boogie works at 9v and the drain voltage setting is about 4.7v. Not oscillation problem for me. I got it, but I solved easily.
After some experiments I didn't get a lot of dynamics, but it's fine enough for this pedal. Not really touch sensitive, but I guess this is the circuit.
#32
General Questions / Re: Dr. Boogie in the 2020
September 02, 2021, 01:13:32 AM
Thanks for the info. Honestly, I don't remember, with that voltage setting it sounds less gainy and aggressive, it isn't? I guess that is the reason it clean up better.

(I assume the big amount of gain doesn't allow to clean up well. I still didn't build a JCM800 fet emulator, but maybe it doesn't have this kind of problem because it should be smoother.)
#33
Ok, I'll try to do something.
#34
I ordered the TL431, the circuit is smaller, so I prefer it, anyway.

For the two BC547 transistor schematic I can't get how I have to set the trimmer to make the LED light up at the voltage I want.

I tried to put a pot in line to the battery and the 9v to decrease the voltage of the circuit. Then I set the trimmer until the LED turned on, but maybe this mess up the voltage, too. Not sure.
I need some instructions I can't find anywhere.
#35
Thanks, ok.
I'll buy a TL431, and I'll see well how I could set the right voltage for me.
#36
Quote from: danfrank on August 07, 2021, 10:28:55 AM
Use a reverse biased zener (1 watt) in series with the LED. You will have to experiment with zener values in order to find the correct one that will turn the LED off at 8 volts. I'd try a 6.2 volt zener first with a red LED. Good luck and please report back with your findings.

I don't use a lot of zener diodes, I don't want ot buy much of them just to try it. I thought this kind of circuit was allowed to set the low battery level.

Quote from: Zerro on August 07, 2021, 10:58:15 AM
This vehement works automatically like switch, which will set LED diode ON, whenewer power supply fall under some level, without some another zener diodes. For 9V battery it is about cca 5V. So, set at power (sensor) pins 5V, and move with trimmer, until it starts to shine. After power is upon this level, cca 6V, LED will be set OFF automatically. Thus it will shine always, when power is low at 5V.

Do you mean I can set it at the voltage I want? :(

I tried to put a 10k pot between the positive of the battery and the 9v of the circuit to tame the power, and see what happen if I low the voltage. Indeed, the LED light up. But I'm not sure it's the right thing, I afraid that the trimmer (or pot) of the original schematic could mess this setting.

I thought to this kind, too. It use just one transistor: TL431.





Or this: https://www.youtube.com/watch?v=T8_7KMBYVEY

I need something I can set the minimum voltage, else it will be a bit useless.
#37
Hello, I never tried this thing, I just got it on the breadboard.



I'm using a 9v battery and it works, turning the pot passing a spot the LED light up brightly, and if I turn it back it light off.

But I don't understand how I can set the minimum voltage. If I want the LED light up at 8v how I can measure it?
#38
Hello guys.
A friend of mine find out that its Mooer PSU didn't work after two months of inactivity.
I noticed that my DIY Tremulus Lune pedal in its pedalboard has both the IC faulty, after I changed both the pedal sounds ok. Other pedals in the pedalboard, Boss, Electro Harmonix and Fulltone was ok.
Why just my DIY pedal is broken?

I admit my DIY pedal had no protection diodes in line to the 9v or across the ground (even I usually include at least one).
I don't know what exactly happened to the PSU, I can say that the LED doesn't turn on and the two poles of the plug (italy plug) "seems" shorted (the multimeter beep breifly), and they measure about 100R of resistance. Anyway it doesn't supply the 9v.
Do you think a diode in my pedal would have saved it?
#39
Quote from: oeslicoalfin on May 22, 2021, 08:47:34 AM
[...]
try looking at Arrow.
[...]

Thank you. I didn't know it. I'll search something at Arrow, too

Quote from: Aentons on May 22, 2021, 09:44:12 AM
If you do buy mlcc from tayda, I've noticed that all the values except 100n have 5mm pin spacing and they don't bend in very well

Yes, indeed, I noticed that. I hope, in case, it won't be a problem. ;)
#40
I often take a look to Mouser, but I find it expensive and it has millions of items that I never found what exactly I wanted. ::)

I'll search some other shop, but I know it's not so ok make an order to buy just some caps in case I need or pay too much what I can find for less money.
We'll see! ;)

Thanks for all the informations.
#41
All these X7R, X5R... I have some confusion.
I found other type in the ceramic cap I can buy.

This is a cheap 1uF monolithic ceramic I could buy.
https://www.taydaelectronics.com/1uf-50v-multilayer-ceramic-capacitor.html
Voltage-Rated: 50V, Tolerance: ±10%, Temperature Characteristic: X7R

This is another one, cheap:
https://www.musikding.de/MLCC-1uF_1
50V, Z5U

This one is more expensive:
https://www.banzaimusic.com/kemet-1uf-63v-z5u-5mm.html
63V Z5U Tolerance: +/- 5%

Should the Tayda's X7R cap be the better? Theorically, at least.
#42
Thanks.
In my next order I'll include some MLCC. ;)
#43
Low profile electo caps will be ok. I used them, indeed.
The problem are the 470nF, 680nF and the most common 1uF film box I use to buy. Those are pretty ok in larger box, but it could be a problem sometime in smaller box.
If I have to avoid tantalum, and the MLCC types are not always a good... Low profile electo caps win for 0.47uF - 1uF value? :D
#44
Hello,
It's been some months I began to use 1590A box (there are some thread here :P).
I use film box caps until 2.2uF, when I found it, electrolityc caps for larger value. And ceramic caps for small value, (silver mica are ok, but expensive, and larger).

I used just in power filter monolithic ceramic 100nF and I always avoid tantalum cap.

But, if in a 1590A or 1590G box I have no much space, is it a bad deal to use tantalum or monolithic ceramic caps just beacuse they are smaller?
#45
Mosfet is a bit noisy, but I think that just one stage won't be so noisy. I built it, and it's ok.