Results 1 to 5 of 5

Thread: Pico Crumble wiring issues

  1. #1

    Default Pico Crumble wiring issues

    Apologies up front, this is a bit of a longer post. I started a build several months ago I wired a Pico Crumble with a RGB Cree XP-E2 CopperNova, 20mm speaker, momentary switch, 18650 3.7V battery. The LED was resistored with Red – 1.2ohm 3W, Blue 0.5ohm 1Attachment 17481W. When I wired everything outside of the hilt and pressed the momentary switch, I would get a single quiet squelch and rhythmic ticking from the speaker every 1/2 second. Neither the accent LED in the switch nor the main LED would light up despite me testing the wiring for each LED die individually (and all of the dies on the Tri Cree all at once).

    I’ve removed the switch from the wiring as well and get the same result when I touch the two wires together briefly – the single quiet squelch and rhythmic ticking.

    I don’t have access to an automated power supply, so all power I’ve been supplying to the board has been through the battery. I’ve tested the battery independently with a multimeter and it’s always exceeded the 3.7V (~4-4.5ish).

    When I emailed Plecter it was suggested that it was a bad amp, so I sent the chip off for testing and on the testing rig the chip was able to light LEDs and make appropriate sounds. So it seems the chip isn’t the problem.

    My math for the LED resistors is as follows.

    Red Cree Part# XPEBRD-L1-0000-00901
    80.6 Minimum Luminous Flux @ 350mA
    Forward Voltage @1000mA = 2.65v
    R = 3.7 – 2.65 = 1.05V / 1A = 1.05Ω
    P (Watts) = R * I^2 = 1.05 * 1 = 1.05 Watts
    1.05Ω, 1.05 Watts so I used 1.2Ω 3W

    Royal Blue Cree Part# XPEBRY-L1-0000-00S01
    650mW Minimum Radiant Flux @ 350mA
    Forward Voltage @1000mA = 3.4v
    R = 3.7 – 3.4 = 0.3V / 1A = 0.3Ω
    P (Watts) = R * I^2 = 0.3 /1A = 0.3 Watts
    0.3Ω, 0.3 Watts so I used 0.5Ω, 1W


    I’ve wired and rewired it multiple times, but I get the same result. Anyone have any ideas if there’s something I’m missing?

    I appreciate any help. Wiring schematic is attached.

    saber wiring.jpg

  2. #2

    Default

    1. What are you using for the Green’s resistor?

    2. We would need to see good, high quality close ups of your actual wiring to see any issues.
    TCSS MODERATOR
    All n00bs READ these first (PLEASE)!!!:
    1. Forum Guidelines
    2. FJK’s “Down and Dirty” guide to Ohm’s Law

    "Yeah, yeah, I've heard it all before... you want blindingly bright, super loud, running 1138 blinkies off of the cheapest sound card you can find AND you want all of it to run on a battery the size of a dime, and run for a very, VERY long time. That one cracks me up every time..."
    My email: fjk_tcss@yahoo.com

  3. #3

    Default

    I hadn't resistored green because the spec battery voltage was 3.7V and the Vf for the green was 3.7. If I calculate based on a 4.1V battery (which is what it seems to be when fully charged) I guess I would need a resistor capable of 0.4 Ω, 0.4 Watts. That's something I can definitely try next if you think it's worth a shot.

    I have an old picture of my wiring, but I've since disassembled this and tried it out of the hilt. So it may not be of the most utility. Please see attached.

    Thanks for your help!

    saber wiring actual.jpg

  4. #4

    Default

    I would put a resistor on the Green. No resistor equals voltage ripple, which could affect the sound. Try that first.
    TCSS MODERATOR
    All n00bs READ these first (PLEASE)!!!:
    1. Forum Guidelines
    2. FJK’s “Down and Dirty” guide to Ohm’s Law

    "Yeah, yeah, I've heard it all before... you want blindingly bright, super loud, running 1138 blinkies off of the cheapest sound card you can find AND you want all of it to run on a battery the size of a dime, and run for a very, VERY long time. That one cracks me up every time..."
    My email: fjk_tcss@yahoo.com

  5. #5

    Default

    I'll give that a shot and let you know. Thanks!

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •