Shared Projects by TimJC

A PCB for making simple/strong dipole antennas for RC or FPV use.

Designed for: - RG316 feed line - 1/32-1/16 (.8-1.6mm) stainless steel cable as elements - Ziptie notches for strain relief

This version has a 5v regulator and is designed to plug into the balance lead of a LiPo battery. It is powered by just the first two cells of the battery and should not result in unbalancing the pack due to the low current draw.

Open source drone racing transponder that is I-Lap compatible.

Changes from Rev 1.3:

• Increased solder pad size for button for easier soldering
• Increased solder pad size for IC1 for easier soldering
• Moved button down for more clearance and easier soldering
• Moved LED2 right for more clearance from IC1
• Altered/added text labels

This is a new updated version of the Alexander Bierbrauer’s IR transponder for multirotor (drone) racing with EasyRaceLapTimer system. This model has a button to allow changing the transponder code at the field. This minimizes transponder conflicts, especially when racing with other groups using the same ERLT system.

This board is intended to be powered by 5V from a spare servo connector on your receiver or flight controller. The hole in the board is for cable strain relief.

Note: ATTiny85 needs to be programmed with applicable code from EasyRaceLapTimer project. This board has not been tested.

Parts to populate each board:

• ATTiny85 SOP8
• MMBT2222A
• 33Ohm 1206 Resistor
• 330Ohm 1206 Resistor
• 1206 SMD LED
• 100Ohm 1206 Resistor
• SMD Tact Switch 3x6x2.5mm
• Infrared 950nm LED LD274-3 or TSUS5202
• 12mm Heat Shrink
• 30cm male to male servo extension (cut them in half for 6 inch leads)

Optional (but recommended):

• 10uF 1206 Capacitor

Required for Programming:

• SOP-8 programming clip
• USBASP or similar programmer

For more informaiton visit:

• EasyRaceLapTimer.com
• GitHub Project Page
• RCGroups.com thread
• Facebook Group

EasyRaceLapTimer Base Station Raspberry Pi Hat

Old static transponders (must be reprogrammed to change transponder ID): 5V SMD R1.2 version 5V Through hole R1.1 version Battery balance port (7-8.4V) R1.2 version

Changes from Rev 1.0:

• Increased solder pads for restart button for easier soldering
• Moved C3 down slightly to allow more room for Pololu regulator
• Moved buzzer down slightly
• Altered/added text labels

This is hat-like board for the EasyRaceLapTimer system’s Raspberry Pi powered base station. This was designed to make cable setup easier, as well as provide an alternate means of powering the system, using a cheap regulator and hobby grade lipo/li-ion/SLA (2-3S) batteries. The board is sized for both the Raspberry Pi Model 2/3, for base station use, and Raspberry Pi Zero/A+/B+, for satellite station use (gate penalty enforcement - not tested).

Parts to complete base station:

• Raspberry Pi Model 2 or 3
• USB WiFi Adapter (not needed with Pi 3, but WILL have better range)
• 2.54mm 2x20 Pin Double Row Female Pin Header
• 5V regulator to power Raspberry Pi
  • Mini 360 DC Step Down Regulator (set to 5V BEFORE connecting to Pi)
  • Pololu 5V, 1A Step-Down Voltage Regulator D24V10F5 - also available here and here
  • A UBEC might also work, but be certain it outputs 5-5.1v, and can supply 2amps. Some UBECs output 5.5-6v which will destroy the Pi.
• 3x TSOP 31238 IR Receiver
• 2x MMBT2222A (T1, T2) <== Also used on Transponder SMD R1.4
• 2x 1kOhm 1206 Resistor (R2, R3)
• 100Ohm 1206 Resistor (R1) <== Also used on Transponder SMD R1.4
• 2x 10uF 1206 Capacitor (C1, C2) <== Also used on Transponder SMD R1.4
• 330-470uF Capacitor (C3)
• SMD Tact Switch 3x6x2.5mm <== Also used on Transponder SMD R1.4
• 5v Buzzer
• Wiring to connect IR receivers
  • 26 AWG servo wire for IR receivers
  • Crimpable servo connectors for IR receivers
• Power lead of choice
• Battery of choice (I use a 12v 8Ah sealed lead acid battery which also powers a speaker system, but a 2s lipo, li-ion, etc will work if you are just looking to power the Pi)

Optional:

• Case to house Pi and hat
  • 3D printable case - top and bottom
• 3D printable mounts for IR receivers
• 2.54mm single row male pin header (only 4-6 pins are needed)
  • Momentary Push Button Switch Panel Mount - Arcade Button, maybe
  • 12v External Buzzer
• Real-Time Clock to maintain time across boots (requires hand wiring)

Parts to create a bad ass sound system for playing the sound effects:

• .50 cal ammo can
• 20Wx2 stereo amplifier
  • 2.1mm by 5.5mm DC barrel connector - if you don’t want to cannibalize the power cord that comes with the amp.
• 4 inch speakers
• 3 foot 3.5mm male to male stereo cable
• 12V 8Ah sealed lead acid battery
• USB WiFi Adapter with External Antenna
  • 20cm RG316 RP-SMA Extension - for mounting antenna on top of ammo box
• Screws and nuts for mounting speakers and amp
• Velcro for mounting Raspberry Pi and battery
• Misc wiring

For more informaiton visit:

• EasyRaceLapTimer.com
• RCGroups.com thread
• Facebook Group

ERLT IR transponders for aircraft