Page 2 of 36 FirstFirst 123456789101112 ... LastLast
Results 11 to 20 of 353
  1. #11
    Alpha22's Avatar
    Alpha22 is online now Registered User
    Location : Cambridgeshire
    Join Date
    Sep 2003
    Posts
    700

    Default

    Quote Originally Posted by Ubergeekian View Post
    I used to teach children to solder from scratch, making up a PCB with 42 joints, including one IC socket. I always got them to start with the socket - good practice, very hard to damage.
    An 8Mhz Pic, two motors, 2 kebab skewers, a sheet of plastic cardboard and some mig welding wire by any chance???

  2. #12
    Ubergeekian's Avatar
    Ubergeekian is offline Registered User
    Location : Me: Castle Douglas, SW Scotland. Boats: Kirkcudbright, Loch Ken, Port Bannatyne
    Join Date
    Jun 2004
    Posts
    9,906

    Default

    Quote Originally Posted by Alpha22 View Post
    An 8Mhz Pic, two motors, 2 kebab skewers, a sheet of plastic cardboard and some mig welding wire by any chance???
    The very ones - they were originally designed for me. Eight hundred and fifty of the little critters I think I built.

  3. #13
    nimbusgb is offline Registered User
    Location : A long way from my boat! :(
    Join Date
    Oct 2005
    Posts
    8,186

    Default

    When its all done and tested get a tin of conformal coating from RS, Maplin or similar and coat the board and components liberally to prevent deterioration from salt air.
    "Tomorrow to fresh woods and pastures new"

  4. #14
    Join Date
    Mar 2005
    Posts
    15,319

    Default

    Does conformal coating make future repairs difficult? I ask because in my youth a friend and I made radio controls for model boats from parts salvaged from old military radio sets. He did most of the building but I stripped the parts from the old sets. When I opened one the works were entirely covered with thick anti fungal "paint" and many of the parts were useless.

    I have now made an executive decision, and will not fit the switches, just bridge the terminal posts. The reason is that I do not want anyone turning them off. I will comnnect them to the bilge pump circuit breaker switch on the main panel, via a concealed switch under the chart table, so that I can isolate them, in need.

    Next job is to do the internal voltage adjustment. The instructions are a bit unclear in that they say connect a digital multimeter reading DC volts between TP1 and TP0, which is clear enough, but then it just says "apply power and adjust VR1 for a reading of 5V. The question is, do I just connect a charged 12 volt battery, which could be anywhere up to about 13.7 volts, or must I connect an exact 12 volt source?
    Last edited by Norman_E; 29-12-10 at 19:30.
    Working on immortality - One day at a time.

  5. #15
    nimbusgb is offline Registered User
    Location : A long way from my boat! :(
    Join Date
    Oct 2005
    Posts
    8,186

    Default

    As I said, when its all tested and complete!

    It's nothing more than a passive varnish, yes it makes desoldering and sometime resoldering a bit of a pain but not nearly as much of a pain as intermittent faults or early fatality of a circuit through the effects of corrosion.
    "Tomorrow to fresh woods and pastures new"

  6. #16
    Join Date
    Jul 2003
    Posts
    1,450

    Default

    Norman - most of these ICs can cope with more volts than 12 but worth checking on a data sheet or wait for confirmation from one more clued up than I.
    I dislike thread drift but........the PIC controlled buggy sounds just the job to stave off the cabin fever. Any chance of link, please ?

  7. #17
    Join Date
    Oct 2005
    Posts
    10,008

    Default

    Quote Originally Posted by Norman_E View Post
    Next job is to do the internal voltage adjustment. The instructions are a bit unclear in that they say connect a digital multimeter reading DC volts between TP1 and TP0, which is clear enough, but then it just says "apply power and adjust VR1 for a reading of 5V. The question is, do I just connect a charged 12 volt battery, which could be anywhere up to about 13.7 volts, or must I connect an exact 12 volt source?
    Do the instructions tell you to adjust it before you insert the ICs? I wonder why it has an adjustment rather than using a fixed 5V regulator.

    Anyway I would adjust it using battery power. It's never going to see an exact 12V supply in real life.

  8. #18
    Ubergeekian's Avatar
    Ubergeekian is offline Registered User
    Location : Me: Castle Douglas, SW Scotland. Boats: Kirkcudbright, Loch Ken, Port Bannatyne
    Join Date
    Jun 2004
    Posts
    9,906

    Default

    Quote Originally Posted by Spuddy View Post
    I dislike thread drift but........the PIC controlled buggy sounds just the job to stave off the cabin fever. Any chance of link, please ?
    It's the http://www.peterbalch.btinternet.co.uk/brainibot.htm. I'm not sure how easy they are to get hold of nowadays - Rapid used to do the kits but I think i was their main customer. IIRobotics in Edinburgh still http://www.therobotshop.com/catalog/brainibot.html, at rather more than Rapid used to charge because they re-engineered the drive train a bit.

    Peter Balch, who designed them, has a prototype Brainibot II with a much more powerful PIC, IR proximity sensors and a USB link for programming, but nobody has ever ordered enough to make production worthwhile.

    If you're interested, PM me and I'll have a look round - I may be able to dig out a PCB and programmed PIC. You'd have to source everything else yourself, though.

  9. #19
    Join Date
    Oct 2005
    Posts
    10,008

    Default

    I Googled for studies of the efficacy of ultrasonic antifouling and came across what appears to be the original source of this design, at http://www.siliconchip.com.au/cms/A_112107/article.html. The article includes this interesting warning that caught my eye:

    WARNING!
    This circuit produces an output voltage of up to 800V peak-peak to drive the ultrasonic transducer and is capable of delivering a severe electric shock.

    DO NOT touch the drive unit output terminals, the PC tracks leading to CON2 or the transducer terminals when power is applied.

    To ensure safety, the PC board must be housed in the recommended plastic case, while the transducer must be correctly housed and fully encapsulated in resin as described here.
    You better make sure you keep it very dry

  10. #20
    Alpha22's Avatar
    Alpha22 is online now Registered User
    Location : Cambridgeshire
    Join Date
    Sep 2003
    Posts
    700

    Default

    Quote Originally Posted by Ubergeekian View Post
    It's the http://www.peterbalch.btinternet.co.uk/brainibot.htm. I'm not sure how easy they are to get hold of nowadays - Rapid used to do the kits but I think i was their main customer. IIRobotics in Edinburgh still http://www.therobotshop.com/catalog/brainibot.html, at rather more than Rapid used to charge because they re-engineered the drive train a bit.

    Peter Balch, who designed them, has a prototype Brainibot II with a much more powerful PIC, IR proximity sensors and a USB link for programming, but nobody has ever ordered enough to make production worthwhile.

    If you're interested, PM me and I'll have a look round - I may be able to dig out a PCB and programmed PIC. You'd have to source everything else yourself, though.
    Ian, I still build them with kids in Bedford. You may remember me, or my wife Mary. I have had PCBs made and sourced most of the components or replacements with Peters help. Getting the code onto the PIC is becoming the biggest challenge. I may rework the board to take a PICAXE to give it some future. I have had a set of the IR Brainibots, but it wasn't as suitable for kids.

    If you have the PIC with code on it then I certainly have a PCB or two to spare. I also have a Rapid parts list for all the components if some one wants a go!!

    Sorry for thread drift, I am interested in the Ultrasonic AF kit and will probably indulge if it works out for you.
    Deano

Page 2 of 36 FirstFirst 123456789101112 ... LastLast

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
  •