Recent content by dxpwny

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    What to uses as an antenna for rf module

    I am playing around with these RF modules I got off Ebay. These: http://www.ebay.com/itm/IC2272-315MH...IAAOSwxg5XyAmv Ebay item #401183214030 are 315 MHZ. I tried a 1 foot 22 solid copper wire wound around a plain pencil, then hung loose, coiled length about 2 inches ... and that worked...
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    How to detect very high frequency sound ?

    The ultra sound sensor is the missing piece. Can anyone suggest a sensor that can deal with about 20 kHz to 50 kHz - not just 40 kHz ?
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    How to detect very high frequency sound ?

    I need some advice on how I might accomplish the detection of very high frequency sound. I do not know the source of the sound, or where is comes from (I don't care and can not answer any questions about that). I also do not know the exact frequency - or range. I know it is higher then what I...
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    ISP Download to DS89C450 using MAX3232 ?

    Yes, all the grounds a tied together. Why is Rx2 / TX1 a problem ? In email I received is says "... you receving on RX2 and transmitting on TX1. Well, that's is a problem." yet I do not see the phrase "Well, that's is a problem." here in the thread. That is a problem for me. Did you edit...
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    ISP Download to DS89C450 using MAX3232 ?

    I'm looking for advice on what I might do to get some RS232 modules I bought to work with my DS89C450 circuit. I bought a variety of RS232 modules off of Ebay, and the ones that use the MAX232CSE work fine. The ones that use the MAX3232ESE do not work completely. All modules allow me to...
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    Solderless breadboards ?

    I am interested in buying some more solderless breadboards. I am only interested in plain simple boards, such as that pictured below - the "Archer Experimenter", #276-174, from Radio Shack. I have not tried the $18 board they sell now. (Imagine an image here uploaded direct from my PC ...
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    3.6v i2C part in a 5V uP circuit

    I wish to use a part the has a max vcc of 3.6 volt, and it's i2c bus in a simple 8051 (DS89C450) circuit. I don't know what the exact 3.6v part is yet - it just seems all the parts I've looked at for my application have a max vcc of 3.6v. I haven't yet read anything in any datasheet that...
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    Looking for 8051 PCB for projects

    Hello ... I have done PCB layouts before ... and could likely do this in a simple two sided board. Can anyone recommend shareware software to generate what ever files a board house would need ? Anyone have good luck with a particular board house doing wimple two sided boards with feed...
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    Looking for 8051 PCB for projects

    I frequently throw together little 8051 projects, always starting out on solder-less bread boards. I get annoyed that I'm always creating the same basic 8051 circuit, then building off of that. I use the DS89C450 (I have dozens), so my base circuit always has the micro, a 74125, a max232 of...
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    Miniture power supplies ?

    I have a few that output +5v at 1 amp. They are realistic because 1) they work and 2) they are real. And .... they are only 1 cubic inch. Those pictured above are HUGE.
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    Miniture power supplies ?

    Yes .... they are 3+ times too big .... like I said in my original post. Thanks though
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    Miniture power supplies ?

    And I'd find a +12v adapter .... where ?
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    Looking for fast camera type flash circuit/module

    I am working on a project where I'd want to generate a flash of light ... and if not too much more of a hassle, perhaps repeatedly, and in rapid succession. It would be for a project that's likely to be in my car (not running) - and could make use of the car battery. I'd like something that I...
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    Miniture power supplies ?

    I frequently do little projects where I want a cheap and small power supply to give me +12v or for some projects just +5v. A few weeks ago while plugging my cell phone into a 120v charger, it occurred to me ... the charger I used with my phone supposedly puts out up to 2 amps at +5v, and has a...
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    Testing car battery

    I am working on a project that requires 12VDC and at least 20 Amps - for maybe 20 seconds, three times a day. The idea of using a used car battery occurred to me. If I look to by a used one, how should I test it ? If I go this route, would it be fine to trickle charge it continuously -...
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