[simpits-chat] Altimeter Question

Tue Nov 4 10:07:28 PST 2003

Hehe. Ultimate irony, sometime down the road I'm planning on building a Tube Amp for my bass! :) And I'm working on repairing an old tube radio that my parents have. So I've got a little experience with the old buggers! :)

Anyway, thanks for all the help with the altimeter stuff. I'm actually looking at switching it over to a Basic Stamp I rather than the 2 - largely because of cost. 2 is about $50, while 1 is about $34. The only main difference is the amount of memory, so if I did go with a 1 I would have to throw out the idea of doing any datalogging, but I don't really care about that so much. As for programming, I think I could manage that, we've got a simple way to tell if we've hit apogee with the accel data, then a preset timer from there, then *poof* out goes the ejection charge.

I need to download some of the documentation, though, and start figureing some of this stuff out. Right now the main thing that is confusing me is the pinouts. The code says out12 for the led, but on the schematic it's connected to pin 17, and pin 4 shows up twice...unless I am completely mis-reading something, which I probably am. Anyway I'm starting to get really excited about this project, it looks like I'll be able to build exactly what I need for a lot cheaper than I could buy one. My one big problem now is finding some way to program the basic stamp - programming boards cost $$$. But hell, I go to a tech school, with a rather large EE department. I'm sure I can find SOMETHING to borrow! :)

Brian

----- Original Message ----- 
  From: John Miguez 
  To: Non-tech or other tech related messages for Simpits 
  Sent: Tuesday, November 04, 2003 7:47 AM
  Subject: Re: [simpits-chat] Altimeter Question

  Hee hee, you younglings need an old fart to tell you about TTL.  Except, I am having a senior moment and can't remember what the first "T" means.  The other two letters are Transistor Logic.  

  Transistors came out when I was a kid.  They are these tiny replacements for the vacuum tube that helped put a man on the moon.  :)

  John
    ----- Original Message ----- 
    From: Ben Jones 
    To: Non-tech or other tech related messages for Simpits 
    Sent: Tuesday, November 04, 2003 3:16 AM
    Subject: Re: [simpits-chat] Altimeter Question

    Brian,

    i dont know alot about the basic 2 paralax stamp , to start telling you yes or no you can /cant do it

    but from the wright up in a electronic catalogue i have  it is noted that the stamp 2 can be connected to " push buttons, led's ,and other TTL level devices,  and with extra components to non-TTL devices such as relays "

    so if this is correct  popping a charge via relay shouldnt be a problem in theory

    the other thought i have is what the F*** is a TTL device , i have never heard of these  in all of my electrical studies .... but hey i get told all the time i always have my head up my ass ... hehe,

    as for modifying ya code  i might have to be solved buy a guru programmer(s) on the list

    regards

    ben
    bjones at pipecomp.com.au

      ----- Original Message ----- 
      From: Brian Sikkema 
      To: simpits chat 
      Sent: Tuesday, November 04, 2003 6:37 AM
      Subject: [simpits-chat] Altimeter Question

      Hey Guys,

      I've got a question, not about an aircraft altimeter, but one I'm thinking of building for model rocket use.

      For those of you into the hobby, you know that even the most basic altimeter good for data logging and, most importantly to me, ejection charge timing, can be very expensive (cheapest I've found to do what I need is about $120). But I've found what seems to be a very nice setup online, here:

      http://www.rocket-roar.com/rap/alt.html

      I'm confident I could build this altimeter and get it working, I know enough to do that, but I'm not quite experienced enough to modify it to what I need it to do (blow an ejection charge). This setup is just a data-logger. What I need is for it to trip a relay at some pre-specified altitude or time after apogee which would blow the ejection charge. This is pretty important, because the launchsite we use up here is very narrow, flanked by a dense forrest on one side and Lake Superior on the other. It's nice and long, but if you drift to the side you're screwed! I lost two rockets to the trees on our last launch, and I would have lost my prized V2 to the Lake had the parachutes not come off on the last flight (thats a funny story in and of itself - I'll tell it later ;) 

      So anyway, long story short, anyone here have experience with PICs and whatnot, who could take a look at the circuit and code and give me some ideas on modding it to trip a relay? I'd be VERY appreciative! :)

      If we can modify this circuit, it could be used for all sorts of useful things, including staging. My mouth waters with the possibilities! :)

      Brian

--------------------------------------------------------------------------

      _______________________________________________
      simpits-chat mailing list
      simpits-chat at simpits.org
      http://www.simpits.org/mailman/listinfo/simpits-chat

----------------------------------------------------------------------------

    _______________________________________________
    simpits-chat mailing list
    simpits-chat at simpits.org
    http://www.simpits.org/mailman/listinfo/simpits-chat

------------------------------------------------------------------------------

  _______________________________________________
  simpits-chat mailing list
  simpits-chat at simpits.org
  http://www.simpits.org/mailman/listinfo/simpits-chat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.simpits.org/pipermail/simpits-chat/attachments/20031104/42dc0ab3/attachment.html