Farm Radio 90V Plate Voltage and 1.5V Filament Voltage

USB test switch

For a simple clock using ATMega328p, DS1337 RTC and Waveshare ePaper Display.

Paper Clock on GitHub

This is the alternate required extension board for use with Quantum Entanglement GWAAMC Aid v1.0 for Arduino UNO-type MCUs. It must be ordered as a flex circuit, which means the project price shown will double when you specify flex, since the price shown defaults to rigid board price. An alternate style of this board exists under a similar project name without the extension board for paralleling two U7s. Either flex board costs the same amount, and the other board will conveniently not require you to cut away the U7 extension if you’ve been careful to get the later value of U7 resistance (50K ohms, recently changed from 100K ohms). However, sometimes flex board substrate material will bubble under a footprint, and while a spare footprint is already provided on the main section, a second spare may be needed. In such a case, the U7 extension can be used as a second spare footprint for the main board section.

The circuit function of this board is to reduce the resistance step size and, of course, total resistance of the MCP4262-502 by paralleling 25 of them together except for their pin 9, which is not used at all. One of the paralleled components is on the rigid main board while the remaining 24 are on this flex circuit board. A spare footprint exists in case one other one would get ruined somehow (like by a bubble formed in the board from heat during soldering). For connecting into the rigid main board, this flex circuit board mates to J9 on the main board (TE connector 1-2328702-0). J9 may be purchased for pennies plus tax from TE’s web site. The U7 expansion auxiliary board must be cut away from the larger section whether you intend to use the smaller board or not.

This is the required extension board for use with Quantum Entanglement GWAAMC Aid v1.0 for Arduino UNO-type MCUs. It must be ordered as a flex circuit, which means the project price shown will double when you specify flex, since the price shown defaults to rigid board price. An alternate style of this board exists under a similar project name that contains an extension board for paralleling two U7s in case you need to halve that dPot’s resistance. Either flex board costs the same amount, but the other board will require you to cut away the U7 extension whether you use that piece or not because it will be in the way of necessary clearance. However, sometimes flex board substrate material will bubble under a footprint, and while a spare footprint is already provided on the main section, a second spare may be needed. In such a case, the U7 extension that the other expansion flex version has can be used as a second spare footprint for the main board section.

The circuit function of this board is to reduce the resistance step size and, of course, total resistance of the MCP4262-502 by paralleling 25 of them together except for their pin 9, which is not used at all. One of the paralleled components is on the rigid main board while the remaining 24 are on this flex circuit board. A spare footprint exists in case one other one would get ruined somehow (like by a bubble formed in the board from heat during soldering). For connecting into the rigid main board, this flex circuit board mates to J9 on the main board (TE connector 1-2328702-0). J9 may be purchased for pennies plus tax from TE’s web site.

Recommendation: Do not populate spare footprints with more devices than the math allows, since doing so would create a gap in “tuning” range by requiring more than 256 dPot steps to target that gap.

Inside the sketch you will find a macro called “DPOT_RATIO”. Set that to be ( signed )248 if you are using the 25 devices recommended. If experimenting with 26 devices, that ratio must be set to no greater than (signed)257 or it would try to set the dPot bank to invalid step numbers.

A breakout board for the Semtech’s i2c GPIO expander. The SX1503 is an i2c GPIO expander with support for 16 extra pins, and 2 voltage translation banks.

Hackaday.io Page

Source at github

Racewire for your qwad. Brushless motor extension to be placed on arms. 9 X 35mm

Board design from Ferdinand Keil,
http://download.ferdinand-keil.de/projekt_btle_emg/projektpraktikum_ble_emg.zip

Isolated Power Supply

Driver board for a Dual-Resonance Solid-State Musical Tesla Coil. This version replaces the old V2 version, fixing its many errata. This design features a zero-current-switching phase-lead circuit, an over-current detection/lockout circuit, an under-voltage lockout circuit, and a PLL-based adjustable dead-time delay. Requires regulated 24VDC power supply. And is designed to be used with the DRSSTC V2.1 Bridge Board and the DRSSTC Bus Supply V2.

This board adds an interface for a thermal (or other) shutdown (See the DRSSTC Thermal Limiter Board V1 ). It also replaces the UCC37322 driver chips on the V1 board with UCC27423 driven FDD8424H push-pull MOSFET pairs for driving the gate-drive transformers, allowing for much higher current gate drive. And, this board also supports “skip pulse” (or specifically “skip IGBT drive cycle”) mode in addition to the “skip interrupter” mode typically used. This allows harder driving to the over-current detector threshold.

Note: Change RV2 and/or R20 to adjust the SG3525 PLL circuit for your coil’s resonant frequency. With the values of 2K for RV2 and 1K for R20, as labeled, it works for a coil with an approximate resonant frequency of 200-250kHz. Changing them, for example, to 10K for RV2 and 6.8K for R20, it works for a coil that’s approximately 45-100kHz. The exact range is dependent on the dead-time setting, as it alters the frequency slightly, and by component tolerance and circuit parasitics. Refer to the SG3525 datasheet for the frequency equations. Note that FreqOut is 2x the resonant frequency due to the SG3525 dividing the frequency for the dual outputs. The Free-Running frequency of the PLL should be set to about 5% less than 2x the primary circuit resonant.

This PCB is for custom personality chips used in R-series and BB-series droids from Galaxy’s Edge. It accepts both DIP-8 and SOIC-8 package SPI Flash memory chips.

Any SPI flash memory chip should work.

Confirmed working: Winbond W25Q16JVSNIQ (SOIC-8), Winbond W25Q32JVDAIQ (DIP-8)

All passive components are 0805, however 0603 should fit as well.

R33: 10k, R99: 10k, C42: 0.1uF, C44: 2pF

I’ve used 15pF capacitors for C44 without issue. I’ve also left it unpopulated and it worked as well. But stock, this capacitor is around 2-3pF.