Electrojolt's Stable PWM Step By Step Assembling Instructions

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This topic is dedicated to provide step by step instructions to assemble my PWM using my PCB

here are the 1st steps:

1st identify the component side of the board:

I recoment using a low power Soldering iron 15 to 30 watt and very thin solder.

Parts needed:
3 555 timers
3 LM311 comparators
1 LM7808 8 volt regulator

2 100uf 35volt electrolitic cap
5 .1uf (104) seramic caps
3 1uf caps
3 10nf (103) caps
3 330pf caps (331)
3 2n2222 or 2n4401 NPN
4 2n2907 or 2n4403 PNP

3 or 6 FCPF11N60 Mosfets get some extra incase you kill some..
4 2.2kohm
13 1Kohm
3 10Kohm
3 100k or 200k or 500K Potenciometer
3 1K Potenciometer
3 10K potenciometer
8 on-on mini togle switches

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Then Solder the Power leads Red and black.

Also Solder the Voltage Regulator LM7808

Stay tuned for the rest, I will be updating this as I assemble this board. I don't have much free time so it will take me a few days.

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Ok, so once the LM7808 and power wires are connected, I add the Filtering caps.

Now these don't have to be a specific value, but a 0.1 (104) and a higher uf value combo will be fine. I usualy salvage them from old electronics.

there are 2 pairs: the set next to the LM7808 is to filter the input power, so the cap voltage rating needs to be higher than the power supply you going to use.

the other 2 pairs, is to filter the 8 volts regulated by the LM7808, so here the cap volatge just needs to be higher than 8 volts.

After the caps are in place, I test the completed circuit Power supply by taking a reading at Pin 8 of the 555 locations.

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Once the Circuit power supply is in place and working, then it is time to solder the 555s and 311s

Pay attention to the chips direction and pins. chips will have a mark to identify Pin 1. LT bottom side of the chip.

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now lets solder some 1k ohm resistors, the color code is Brown Black Red, I have tested 1/8 watt and it works fine, and 1/8 is what I'm using.

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Next I solder some (3) 0.1uf caps, these go between pin 5 and ground on the 555s.

Notice that the caps are installed on the holes closer to the 555s, the other 2 holes are for additional and option 8 volt power filtering.

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Next I solder 3 jumper, initially this spots was to place 3 switched, but then I thought that using a jumper and 2 switched would do the same job and simpler.

So the Jumper will collect the lowest value cap to ground, and the 2 toggle switches will add the 2 other caps to the cap bank slowing the pulse rate (freq) down, this will provide the wide freq range selections.

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Ok, next I solder 3x  2.2 Kohm resistors, you can use up to 3.3kohm. I'm also using 1/8 watt here