Shared Projects by Barbouri

IceTube Clock mainpcb from Xmas icetube Rev D. Modified component placement, trace width, and routing. Removed GPS battery connection pad. Added component values to top silkscreen. Improved ground-plane coverage. Added C12 bypass on IC5 (LM317), changed R4 from 5.6K to 10K, improved component value silkscreen. Improved ground and power trace width, increased Awake trace width, improved ground plane cutout for battery holder. Increased trace width for segments 1 and 9, increased DQ trace with for IC4 temp sensor. Changed IC3 footprint to TO-220 vertical which supports both footprints (78L05). Changed R4 footprint to a smaller 0204V vertical footprint Increased AC1 and AC2 trace width to support 85 mA current with less voltage drop. Revision 2.2

https://www.barbouri.com/2020/03/26/updated-icetube-clock-design//

IceTube Clock Main board Ver. 2.2

Hewlett Packard 5300 series Display module test card Rev B. HP manual Fig 5-2 Tests: 1 - 4, 6 - 16 DP4 test jumper Rotary switch for test #9 Annunciators and DP 1,2,3,5 Breakout terminals for Power Supplies, GND, and Reset

https://www.barbouri.com/2022/04/29/hewlett-packard-10548a-diagnostic-service-kit/ Assembled board with jumpers

CuriousMarc’s HP 09825-66552 Crowbar Circuit Reproduction.

Crowbar protection circuit for the HP 9825, 9835 calculator

https://www.curiousmarc.com/computing/hp-9825-scientific-computer#h.xrov16yr03br

USB-2 Micro-B to Isolated TTL serial 4 pin header, using a UMFT234XF FTDI module. Version 2.2

https://www.barbouri.com/2022/03/31/isolated-ttl-serial-to-usb-2-0-converter/

Assembled Isolated TTL serial to USB board

Programmable Voltage Reference 0.001 to 5.000 Volt - Version 3.15 UNTESTED

The Programmable Voltage Reference (PVR) has a range of 1 mV to 5.000 volts in 1 mV steps. The accuracy is plus or minus 50 uV for any set value. The reference value is displayed on a 2 X 16 character OLED display and can be set manually using the rotary encoder, toggle switch, or remotely over the TTL serial to isolated USB 2.0 port.

https://www.barbouri.com/2022/03/29/updating-the-programmable-voltage-reference-project/ Front panel with display view