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555 Headphone Tube Amp (fightcube) (750) Schematic

555 Cradle Swing Upgrade (fightcube) (462) Schematic

Update 2:

The 555 board for the cradle swing is finished and installed.  For video proof check out this link:

A schematic is also posted above.

The headphone tube amp is also finished.  the high voltage for the tubes is generated by a 555 in astable mode driving a fet and a custom hand wound transformer. For video proof check out this link:

A schematic is also posted above.

Thanks to fightcube for the assistance on these projects.

UPDATE 1:

The board is assembled minus a few minor components. Powered it up, and took some waveforms. Looks pretty good.  all i need is a pnp transistor or p channel fet and or a base resistor to supply the 5v to the micro.   While i was at it i took some pictures of my headphone tube amp power supply. I’m not too far from being finished.

UPDATE:

I hacked the thing apart and started probing…the swing runs for 7 minutes and 15 seconds, then the lights and sounds shut off.  There is a reset button that turns the lights and sound back on for another 7 minutes and 15 seconds.  This has become really annoying as my daughter loves to watch the fish rotate around and the light bowl change colors all while the ocean surf sound is playing.  so, every 7 minutes someone has to go push the infernal “BUTTON”. This is crazy if you are in another room or in the bathroom.  So, i started probing the circuit to see what kind of signal is going to the “Chicklet” TM Microprocessor when you press the button. Turns out it is 5v. So i built a 555 circuit driving a PNP transistor.   I will post the schematic later.

The 555 contest is coming, and i have decided to try and submit 2 entries…1: A 6DJ8 stereo headphone tube amp powered by a 555 switcher circuit, and 2: a simple astable timer to reset a baby cradle swing’s lights and sounds. The headphone amp is done just needs some repair-I had to disassemble it to make schematics of the power supply and the amplifier sections. The cradle swing circuit needs to be breadboarded-i have a target of 7 minutes and 15 seconds to reset the lights and sounds. I have to wait until the lights stop before i can re-trigger the switch, if i try and pulse it before then it does not have any effect.  I will update this post when something changes.

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