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  1. H

    Question About Resistors

    That's not necessary. I have the resistors, and I understand what they do in a circuit, I was just curious as to the placement option in the circuit. With Mr. Kapp's explanation of the "tricking the circuit" with the increased current draw, instead of just adding resistance to the circuit, I...
  2. H

    Question About Resistors

    Thank you, Mr. Kapp.
  3. H

    Question About Resistors

    Hi all. I have a question about the placement of resistors in a circuit. In this application, the circuit involves LED's in an automotive turn signal. Newer vehicles, originally built with incandescent bulbs, flash normally with the original bulbs. When replacing the bulb with an LED bulb...
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    Capacitor Substitution

    OK all. I have to report a success here. Thanks for your help. Today, since there weren't really that many of each, I decided to pull a leg off of all of the resistors, diodes, transistors, etc., and other easily testable components and do just that...test them. Everything tested ok, so I...
  5. H

    Capacitor Substitution

    Are you able to tell me if these are the "sense resistor(s)" you are talking about? They are low value (.1 Ohm) and are in parallel with each other. One end is in circuit contact with the number three leg (source) of both of the mosfets (IRFP450). You can see the connections in the photos...
  6. H

    Capacitor Substitution

    I replied above.
  7. H

    Capacitor Substitution

    Sure. Here you go. Note that although there was substantial heat there, the resistors are still measuring out correctly. The top portion of the board does not have any burn marks. The shroud on the mains does though. There are cotton fibers from a q-tip on some of the pointy solder bits in...
  8. H

    Capacitor Substitution

    OK. There are pictures of the mosfets above. Is he asking for more than that? Forgive me if I sound like I'm an amateur, but I am. :-)
  9. H

    Capacitor Substitution

    There are two gray parallel resistors (.1 Ohm) just directly above the two large caps in the photo above. They both test out at .1 Ohm, however, the one on the left seems to rise up to .4 Ohm and then back down to the correct value. That is quite a percentage-wise fluctuation. Are those the...
  10. H

    Capacitor Substitution

    It is some type of substance on the device, a hard clear glue like stuff. It is not chipped. Like davenn said.
  11. H

    Capacitor Substitution

    Hunter64, I have attached photos of each component that could be an "IC." And a photo for location reference. I think you are looking for the KA3846 or MC34072P, though. I don't understand your question about "what is the TO-220?" Can you explain what you are asking for please?
  12. H

    Capacitor Substitution

    OK, so I have checked every solder connection and made sure there are no cold solder joints anywhere on the board. I removed and tested the mosfets (IRFP450) on the right side of the board against the heat sink and have done the same with the diodes (MPR4060PT) on the left side of the board...
  13. H

    Capacitor Substitution

    Well I thought I had this fixed after replacing the caps, but in real time use, it is still not working correctly, so I'm back for help. This is a Parallax Series 7100, Model 7155, 55-amp RV Power Converter. It is very widely used in the RV industry. It will power the 12 volt systems and will...
  14. H

    Capacitor Substitution

    Thank you, too, dave9. I'll be ordering shortly. :-)
  15. H

    Capacitor Substitution

    Sir 73's de Edd. Thank you for your reply. I am confident, with your reply, that I can substitute the 1000uF for the 950uF. Replacing both of them at the same time was my intention. One of them had a slight bulge and was leaking. Your observation about that other cap is absolutely correct...
  16. H

    Capacitor Substitution

    Hi all. I have tried to find a definitive answer to my question on my own, however, I am not confident in what I have found. This was my last, but obviously, most trusted attempt. I realize substituting capacitors with higher voltage and temperature ratings is acceptable, if you cannot find...
  17. H

    WiFi Antenna Composition

    I see it now. Thank you.
  18. H

    WiFi Antenna Composition

    Thanks for clearing that (the reason for the unseen replies) up steve. Part of the reason for my comment above and about the new format didn't include the fact that I can no longer see the posts I have personally made or replied to and am unable to tell if any additional replies were made to...
  19. H

    WiFi Antenna Composition

    I have a couple of email requests asking if what Steve described was correct. These are recent questions to my otherwise original and older post that are not showing up in this thread for some reason. Not really a fan of the new EP format now either, but anyway. The black wire, with a...
  20. H

    Recapping pc motherboards.

    I've done a few re-caps as well. I mostly use dave9's method for removal, but instead of using a needle or anything made of steel after cleaning with the solder braid, I use a wooden toothpick. The toothpick will open the hole without sticking to the solder. You heat the remaining solder and...
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