Macrofab Engineering Podcast

Podcast Notes Parker is working on streamlining the Selective Solder Process at MacroFab. Writing a script that will take XYRS data and generate the G-Code for the machine. Design work on a calibration board for visual systems like the SAIM and calibrating the Selective Solder is being designed. Stephen is getting the analog side of the SSPS working. The -35V rail has a blown transistor. He found that pnp transistors were flipped C to E! After testing the circuit node by node, Stephen found some deviations from the simulation. The feedback voltage was supposed to be about 34 volts but it was reading 15.2 and -1.78 for both regulators. Put the scope on the fb nodes and found that the + error amp was oscillating at 12.6kHz and the - regulator was at 2.4kHz. Both error amps has insufficient control feedback. Added a 1M resistor with a 100uF cap in parallel and the oscillation went away. See Figure 1. Engineering click bait article titles. Parker came up with "5 Cost Saving Tips No Contract Manufacturer Wants Yo