EP#145: The Vox in a Box Roxs

EP#145: The Vox in a Box Roxs

  • Stephen's Vox in a Box
    • Preamp Design
      • Vox AC30 preamp - 3 gain stages with a cathode follower and a phase inverter
      • Phase inverter - create differential signals for the power amp input
      • Drop signal using voltage dividers and mosfet buffers
      • 320V phase inverter to 18V buffer drive
      • Built point to point on an aluminum plate for easy modification and testing
    • Power Amp Design
      • TPA3116 Class D amplifier
      • LM311 comparator mute circuit for start up mute ~5 to 10 Seconds
      • Runs at 400KHz - Left open pads for boosting this up to 1.2MHz
        • Is there an advantage at running at higher frequencies?
    • Power Supply Design
      • TPS40210 Switching controller into a diode/cap ladder voltage multiplier
      • 7 stages of multiplication leads to ~50V per stage
      • Variable Switching from 35KHz to 1000KHz
      • PMP8621 Appnote
    • Testing the Vox in a Box
      • Been going nonstop for weeks now
      • Have taken it up to nearly 60 Watts without problems
    • Layout of the PCB
      • Multiple ground system with master start
      • Each sub circuit has its own ground return
      • 8 Master star ground returns
      • 4 layers
    • Issues with the current design
      • High Voltage SMPS does not like high capacitive load
      • Ground for signal input is very important - Nearly all noise is dominated by this single point
        • Alligator clips for signal patching are not low noise…
      • Cold Heater impedance
    • Current Schematic for the Vox in a Box
    • Fusion 360
      • New amp design
        • Learning by building a virtual amp
      • Vox in a box
        • Going to model the whole design to ensure proper fit
  • R.F.O.

Tags: Chris Gammel, electronics podcast, Fusion 360, Hackaday, LM311, MacroFab, macrofab engineering podcast, MEP, PMP8621, Preamp, SuperCon, TPA3116, TPS40210, Vox AC30, Vox in a Box

Jaksot(448)

EP#8: Bits That Don’t Quit

EP#8: Bits That Don’t Quit

Podcast NotesStephen and Parker do a live discussion on how the digital and analog side of the Super Simple Power Supply will interface with each other. MultiSim has been a huge part in simulating the...

25 Maalis 201639min

EP#7: The Art of Retention Force

EP#7: The Art of Retention Force

Parker has almost finalized the front panel design for the Super Simple Power Supply. Going to have a "VU" meter for how much power it is pulling.Parker is also still looking for a proper encoder that...

18 Maalis 201624min

EP#6: Mythical Transistors

EP#6: Mythical Transistors

Podcast NotesParker is still working on the Super Simple Power Supply. He is designing the front panel. He is considering using some WP1043 Kingbright LEDs.Super Simple Power Supply will have two deci...

11 Maalis 201625min

EP#5: Tilting Tubes

EP#5: Tilting Tubes

Parker ordered all the parts for the SAIM this week. The v-slot rails and brackets from OpenBuild, iES-1706 servos from Leadshine, and 3D printed parts from Shapeways.MacroFab uses 3D printed parts to...

4 Maalis 201647min

EP#4: Linear Effects of Licensing

EP#4: Linear Effects of Licensing

Audio quality of the podcast leveled up! Stephen and Parker went over to The Pharmacy Recording Studio which is run by Josh Moore. He hooked them up with 2 (!) microphones and a nice an acoustically p...

26 Helmi 201617min

EP#3: Liquid Toroidal Electrons

EP#3: Liquid Toroidal Electrons

Stephen and Parker have been testing the main opamp for the OPA541. Stephen wrote a blog post detailing the opamp tests with simulation and real world testing.GitHub link to the repository for the SSP...

19 Helmi 201622min

EP#2: Mechanical MultiSIM Monsters

EP#2: Mechanical MultiSIM Monsters

Stephen continues his work on the Stupid Simple Power Supply (SSPS). He decided to go digital voltage control over analog. Also he has been trying out MultiSIM BLUE by Mouser for circuit simulation. S...

10 Helmi 201620min

EP#1: Opamp-timal Power Supply

EP#1: Opamp-timal Power Supply

Stephen talks about the Stupid Simple Power Supply (SSPS). He designed a OPA541 breakout board for testing. See figure 1.OPA541 Datasheet : Street price of $21.88.Parker brings up that blinky LEDs are...

9 Helmi 201623min

Suosittua kategoriassa Tiede

rss-mita-tulisi-tietaa
tiedekulma-podcast
rss-poliisin-mieli
docemilia
rss-duodecim-lehti
utelias-mieli
filocast-filosofian-perusteet
rss-laakaripodi
rss-opeklubi
rss-lihavuudesta-podcast
rss-sosiopodi
sotataidon-ytimessa
mielipaivakirja
radio-antro
rss-radplus
rss-luontopodi-samuel-glassar-tutkii-luonnon-ihmeita