#2000 Megadrone

Thank you to everyone who helped me figure out what I was doing wrong. The power supply was reversed polarity, I was able to reverse it back with the tip by spinning it around and then everything worked. Here is a video of my megadrone turning on.

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Female in header for me.

what color led’s did you use and if not red then did you change the resistor ? thye look blueish white from the video. I know you have to use a larger nuber resistance fior the (other than) red led’s like blue I was just seeing what people are using and such .

I use the same resistors as are called for in the design. I did not swap them out for something else. I didn’t realize different resistors were necessary for colors other than red.

Blue and white LEDs tend to be much brighter, but they can handle the same currents and here the LED is part of the oscillator circuit so if you mess with the resistors you have to change the capacitors too. If you’re happy with the circuit as is, there’s no need to change anything.

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Single Row Female Pin Headers will fit the MOSFETs. SIPs sockets are def too small, but the right size for socketing the caps.

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Finally finished mine. So nice sounding :ok_hand:

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No idea whats wrong here but im getting nothing out nor any lights. Top row is 1 uF caps, bottom row is 10 uF. My guess is that its not working because I replaced the SS9018’s with 2N3904’s because allegedly they’re equivalent.

Oh also I have the 200k trimmer facing out the front but it still has the screw up top

Yes, 2N3904’s begin to oscillate around 18V, if you use a 12V power supply for this PCB you really need some SS9018 (oscillate near 8V)

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Setting myself a calendar apointemtn to bring my two ( one not working, one not started) drones to my workshop so I can have a better go at getting them working.

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Still struggling with this one, not much I can think to check now.

4 out of 6 oscillators seem to work ok the other 6 are seemingly maxed out.

But so far eveything checks out, all joints re-flowed, caps changed between non/working channels, same for FETS, tried replacing the transistors… Diodes checked, resistors checked…

I think I am going to have to breadboard it and verify the components all again… Maybee it’s the cheap POTS but they seem to check out ok…

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Guys be very careful if you are going to try and remove caps (or anything else). I removed one cap and the pads came up with it. I wanted to change five to a different value but thats not going to happen now. :frowning:

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I have worked out a mod (hack) to fix it. I have changed all the caps to 33uf. I love the deep droning filth.

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this is what I did with mine to avoid re soldering . cut down ic sockets .
will probably hot glue in place once I decide which values I like the best .

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Hey to the megadroners !

I cant manage to find a elko/electrolytic cap with 47nf anywhere…
Is this the right part to get ? Or can i exchange it with another type ?
Or am i just searching wrong…
I use uk-electronic.de for sourcing.
But i also wasnt able to find one anywhere else…

Have a great time !

Yeah, electrolytics usually don’t go that low (0.1 uF = 100 nF tends to be the smallest you can get). Any reason you cannot use a film or ceramic capacitor?

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Ahh very good to know !

56, C10 → its that position in the BOM, so i figured it would be mandatory to use that exact part…
Does that mean that it is wrongly written there ? What did you use for C10 ?

in the schem it seems that not a electrolytic one

but in the BOM

Okay well then ill choose a film / ceramic one that suits !
Thanks for pointing that out !

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@lookmumnocomputer This is an error in the Megadrone BOM, should be film or ceramic, not electrolytic

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