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bob345

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Everything posted by bob345

  1. bob345
    just because the speakers are rated for 120 watts does not mean they require a 120 watt amplifier. 80 watts will drive those speakers with no problem at all. 4 ohms is 4 ohms regardless of what the max rms power the drivers may be rated for.
  2. bob345
    The proper way to do this would be to use a hot air station to reflow the solder at which point the part can easily be picked off the pcb. I would not recommend using an iron to remove any surface mount components as the small pads can easily be damaged or lifted. Hot air reflow is the only way to do it right IMO.
  3. bob345
    Not sure where you are seeing vcc connected to ground. Just for reference, connections on a breadboard do not cross over the center gap. The breadboard layout you provided just has vcc floating. As others have already said, typically the power source for your motor will be isolated from the logic. One reason this is done is to isolate your more sensitive electronics from potentially harmful inductive spikes. Another reason is to allow the use of an entirely separate power source that can provide allot more voltage & current. Most mcu's are only going to run off of 3.3-5v where as it is fairly common to use a motor anywhere from 12v-48v or even higher.
  4. bob345
    Just got this HP/Agilent E4432b rf signal generator.
  5. bob345
    id get a multi-meter and check for a short. In an automotive system, i wouldn't worry about getting electrocuted as the voltage is far to low, but with that much current a fire is far more likely if something goes wrong. where is your fuse located? is it only at the amp or do you have one at the positive terminal of the battery?
  6. bob345
    how about current? if you turn the current limit knob can you see a change on the meter? If everything but voltage control is working it you should be able to adjust the current up and down with the output shorted
  7. bob345
    I doubt its a blown potentiometer. The pot doesn't directly control your output voltage, it will control the main output transistor which will regulate the voltage. More than likely the output transistor will be shorted source to drain which would cause the behavior you are seeing by just passing the mail power rail voltage straight through with no additional regulation. Should be an easy fix as long as you can get a hold of the correct or comparable part.
  8. bob345
    As this is the hobby electronics section, I think we are lacking a thread to show off all of our electronic workbenches/labs that we have at home or have access to. so go aherad and post a pic you the workbench you use and maybe list your favorite equipment or tools that help you get the job done. Here's my bedroom workbench. I'm going to need more room soon. just some hp scopes, rigol power supply and siglent spectrum analyzer
  9. bob345
    So they are using circularly polarized light? I thought that was already a thing, It is in radio.
  10. bob345
    Kicad is the best free option aside from eagle when it comes to free eda software. It my preferred choice right now as altium is still a bit over budget for me. Kicad is prey good when it comes to availability of parts libraries. Snap eda is my go to source for kicad footprints and symbols Here is an example of one of my recent projects in kicad
  11. bob345
    Siglent Sva1015x spectrum analyzer
  12. bob345

    My MAZDA

    bob345 replied to Beef Boss's topic in Off Topic

    *cough* @terrytek
  13. bob345
    It's cheap because it's an s4. If you want a car that's up on a lift more than one the road the s4 is a perfect car.
  14. bob345
    Really dude?
  15. bob345
    can you tell me how the Fahrenheit scale is better? Heres the thing, The large majority of the world uses C, and as such all major industries use it for measuring temperature. " Much like the metric system it's just not that accurate without going into "large" decimal values " Uhhh what? you dont say 0.01 millimeter, you say 10 micron. The metric system scales WAY better than the imperial system ie 1000 meters is 1 kilometer. How many feet are in a mile? 5280. You say metric doesn't convert well but what the hell is that?
  16. bob345
    Lab results like this don't matter much to the consumer or tech world. Proving a concept with a physics experiment is one thing, actually having something you can mass manufacture is something entirely different.
  17. bob345
    You might want to give the STM32f469I a look. Pretty good mcu imo.
  18. bob345
    8/10 Looks good, really captures the atmosphere pretty well. Here's a shot I took on a trip in NYC recently trying out my new 35mm f2
  19. bob345
    if you want a simple antenna, just connect a wire roughly 30 inches or 75 cm long to the center pin. That should be adequate for a simple quarter wave antenna. Double those lengths for a half wave antenna and a bit more gain. FM signals tend to be pretty strong so it shouldn't take much unless you are in the middle of nowhere. If that's the case i would look into building a simple yagi antenna. Yagi's are highly directional so you need to know what direction your source is, but you wont get much better for a simple diy antenna when it come to gain. Lots of tutorials online on how to put one together. Also, dont worry about impedance too much, matching 50 ohms isn't super important if you are just using a receiver as there will never be any reflected power.
  20. bob345
    I would use a logic level converter, you can get a pack of 5 small boards for next to nothing. you almost never want to use voltage dividers on digital i/o.
  21. bob345
    That's insane that they would cite someone for something so trivial like that. Do they literally have nothing else to do? Im also pretty sure that would be an illegal citation, at least in my area, as there are no laws for interior lighting aside for "impersonating emergency services".
  22. bob345
    This isn't under glow, its just interior accent lighting. There is nothing illegal about that. If you run lights that are meant to look like flashing police/emergency service lights though, that is a whole different story.
  23. bob345
    Lots of standardized automated equipment. Same thing applies for pretty much any sized pcb.
  24. bob345
    hard to say, i know Panasonic makes similar board to board interconnects, but its impossible to tell without knowing dimensions and pitch of the connector. Looks to be a panasonic AXK724147G, but you will have to verify that yourself by measuring the connector and make sure everything matches the datasheet. https://www.digikey.com/product-detail/en/panasonic-electric-works/AXK724147G/255-2535-1-ND/1986698 the other side should be this, but it would require you to make your own pcb breakout to make a cable for it https://www.digikey.com/product-detail/en/panasonic-electric-works/AXK824145WG/255-2528-1-ND/1986691
  25. bob345
    Taking the wrx to another autox event tomorrow. Finally get to really test out my new wheels and tires. Pretty interesting course as well.
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