Wireless Turning Signals Indicators - Retro Fit/Design

Discussion in 'The Projects Forum' started by richardu, Nov 14, 2015.

  1. richardu

    Thread Starter New Member

    Nov 14, 2015
    Firstly hi all,
    I'm a closet geek, old physics degree and currently working on an older VW Camper Van re-fit.
    Out on the roads, which grow ever more busy, I'm small and poorly illuminated - which drove me to thinking, could I dismantle an available wireless turning signal system and integrate it into the van, or build my own? I'd much rather build my own as it'd be more fun.

    Has anyone had experience with such a circuit?

    Many thanks, boy I'm going to love this site :)
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    It is possible but there is a lot of interference around a car and all the iron alloys make low-power transmissions difficult. Finally, of the available bandwidth, your device is subject to lots of interference and possibly false positives or non-activation.

    All kinds of low power 433 MHz transmitter/receiver pairs are available on eBay for less than $5 including shipping.
  3. richardu

    Thread Starter New Member

    Nov 14, 2015
    I see your point GT, a false +ve on the highway and I could cause an accident.
  4. MikeML

    AAC Fanatic!

    Oct 2, 2009
    If you get the Chinese keyfob 315MHz or 433Mhz transmitter with the built-in encoder chip, and the matching receiver with the decoder chip, strap them for a random code, the probability of false positives will be very low. There may be cases where other nearby transmissions will block the proper decode of any given attempt to send a command...

    I have been using the 315Mhz ones to control my garage doors and swing gate. Here, in a rural setting, they are very reliable. I have never seen a false positive. I occasionally get a missed transmission where I have to repeat the command.

    The receiver is a super-regen that is as wide as a barn door. I can block the 433MHz version just by transmitting in the 70cm Ham Band. That is a 50W transmitter within ~10MHz of 433MHz, within the same building. For this reason, I choose the 315MHz version, because in our area, there are no nearby transmitters in that band...

    I would worry about this in a very urban area, where there would likely be lots of nearby transmitters, especially in the 420 to 470 MHz region.
  5. GopherT

    AAC Fanatic!

    Nov 23, 2012
    Also, will need some type of self, canceling feature and it would be nice to have some feedback at your dashboard to see if/when a flasher is actually on (even if it is falsely triggered).
  6. #12


    Nov 30, 2010
    Forgive me for being an old geezer but, why use 100 transistors to send a signal to a light bulb that needs a power wire anyway?:confused: Am I that far back in the woods that I don't know light bulbs now work without a power source?

    It's possible. I recently found out I have bought a used car in which none of the door locks or window motors or key fob functions work while the driver's door window control module is disconnected. Still, that's a case of wires to every lock solenoid and window motor in the car, but no rf signal. How are you going to do this with no wires to the turn signal bulbs? If you are going to have wires to the turn signal bulbs, why not just blink the power source?
    shortbus likes this.
  7. AnalogKid

    Distinguished Member

    Aug 1, 2013
    I'm with #12. Assuming the van already has wired turn signals (!), it sounds like the problem is more light, not additional lights. LED's?

  8. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    If it were me I'd forget the wireless setup, run an extra power wire to auxiliary lights (so as not to overload the existing wiring), and slave the power switching to the existing blinker via a FET (thereby avoiding blinker overload) . I'd also seek my insurer's approval for the mod ;).