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oldgrandpainmi's Achievements


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  1. Honestly, I haven't had the manual out in 10+ years, but the basic tools you need are a DVM, a scope, a high voltage probe, among others. I never did my scope because of the needed tools. My company I USED to work for refused to do their own scopes, so they had them sent in. I don't think I could trust my own work, if .01% accuracy is needed (for example). If you get it and it works on the 1khz test jack, for the most part, it will be accurate enough to do hobby work. The easiest way to see what is needed, after all is said and done, is to find the manufacturer of the scope, download the manual, and check out the adjustment section. All the necessary tools and test equiptment is listed. oldgrandpainmi
  2. Bmachine, Sorry about the drawing. Had I known that you were a real newbie, I'd have added the base resistor to the transistor, the current limiting resistor to the LED, and etc., but I see that Audioguru has it under control. The intent of the drawing was to give you ideas for you to design your own circuit. (it's a bad habbit, from helping my kids and grandkids with school work. Give them help, not the answers.) Fog maching and light machine? Does "B" stand for "bowling"? I did the same basic thing for a bowling alley I used to work for years ago. Good luck!!!! oldgrandpainmi
  3. Not knowing a lot about the scope you are going to purchase, and considering you views on accuracy, 2 of my past Tektronix scope's and my BK Precision have a 1khz squarewave calabration timebase output to check the probes, and accuracy check. If this is the closest to accuracy you want, then calabrate to that timebase. If you want the best accuracy you can get, then have it setup by a repair shop that deals with scopes. My BK has several pages of calabration checks, and to put them to 99% or better, It was suggested to take it in to a local service department. Just remember that the general setup checks must include a CRT check. As componant's degrade, the screen can show the system may be out of alignment, when actually it is the CRT that is showing up as degrading. Also, when dealing with a scope and eBay, ALWAY's get insurance and a written agreement against D.O.A.!!! Scopes take a beating while being shipped. The CRT neck may crack with one good bounce, then you are out of luck. C.Y.A. is my first thought when dealing with fragle items on eBay. Good luck, oldgrandpainmi
  4. Hello all, I was always taught that I should drive a passive part with a transistor. (old school) I have included a quick drawing. I drew it because I don't know Bmachine's background, and Audioguru's explaination could be a little confusing to a newbie. The Damper Diode (supression diode) is hooked up in parrellel to the coil, and is hooked up in 'reverse bias' as shown. (Audio, a newbie MAY hook the diode up in series with the 555 and the coil, or, hook it up in forward bias accidently) I didn't go crazy with the drawing, leaving the additional designing to the builder!!! oldgrandpainmi
  5. MP, Makes more sence that what I've been running into. 1000pF=1nF 1000uF=1mF Etc. Just have to remember to convert and re-convert before I look for parts in my suppliers manuals,
  6. The error is simple...... If, for any reason, your download is interrupted, you cannot "resume" where you left off. You must start from the beginning of the file to download it. Download manager programs will not help here, as the program provider does not support it. oldgrandpainmi
  7. Raccoon, I'd build it, just for the fun of it! There is allways a better feeling saying "I built it myself", than "I bought it"!!! Besides, as you learn the circuit, there will be a little voice in you head that will say "Maybe it will be better if I .........."!!!! Then you can say, "Mine works BETTER than that store bought unit. Here's why!!!" Happens to me all of the time!!! oldgrandpaini
  8. Sarah, If you take awright's advice (which is great), I'd advise you to keep an eye out for some old computer motherboard's at flea market's, garage sales, etc., and strip off the speakers from them to use. They can easily be desoldered and used in the circuit you are using. Besides, the cost on these old, junk, motherboards can be cheaper than buying a new buzzer/speaker, and you can salvage additional parts for your projects. I've seen old motherboards for $1. Depending on your need's, this will help keep the project small. Just food for thought!!!! oldgrandpainmi
  9. Hello all, I hope you can give me advice/information an where I can get some coil forms for construction of a 1mH and .22mH air core crossover inductors. Yeah, I could buy them a lot easier from a couple sources, but I'd like to see if I could build them for fun, first! I had been hoping to salvage some from an old speaker, but have yet to run across any. I used to throw these things out regularly, but have yet to see any now that I need them!!!! Murphy's Law strikes again!!! The forms need to have a 1.6" (1.5") and 1.16" (1.25") core diameters, and the heights need to be .4" and .3" respectively, per an inductor program I found. The core diameter is I bit bigger that I want, but it is due to the magnet wire diameter I am going to use (22guage). This will put the power rating of each at about 100w RMS. I don't have a pic of the form, but if you can picture an empty fishing line spool, this is what they look like. I've emailed several places, including Amidon, for forms and/or information, but still have had no reply's. I am looking for your guy's advice first before attempting another avenue. Thanks!! oldgrandpainmi
  10. Shelby, I didn't go thru all of that with the iron. Just replace the tip locking screw with a longer one and use it to clamp the needle into place. Nothing else needs to be done. When done you can replace the needle with a new (or old) tip. oldgrandpainmi
  11. I got a reply from the author. Yep, a nonofarad (n) = a nanofarad, but a Microfarad (m in Europe) = uF U.S.! I figured that if they used a different symbol for Micro, then they would have used a different for Nano, which isn't the case. Thus the confusion. Also, L1 is a .22mH (220uH) not a 220mH as stated throughout the artical. I found a neat link on how to build these inductors here: http://colomar.com/Shavano/inductor_info.html oldgrandpainmi
  12. Hello all, Just my 2/100 of a dollar! If a small enough soldering tip can't be found or made, what I've done in the past is to get a cheapy, dual wattage, iron from Radio Shack. It has a screw in tip with a set screw to lock it. Remove the tip and insert an leather sewing needle. Break it to length, to fit your needs. The shorter the better. I have found that running at 30w is sometimes needed, as it now has a terribible heat transfer ratio, so you will loose a lot of heat, but for chip resister, caps, etc., and small SMT devices, it works reasonable. You can also try different needle diameters or the other 15w setting to get different results I have also found that when trying to desolder a SMT, 555 timer, with wick, it is a bit easier to float solder over all 4 pins (on one side) at once, then use the wick. Doing one pin at a time, like a dip package, can be tough. Food for thought, although a bit off of the origonal subject! oldgrandpainmi
  13. Ante, I downloaded your circuit and will look at it further this evening. I did notice that the primary voltage is 230vac at 50hz.
  14. Kasamiko, I just got home from work and looked for your reply, then it hit me!!! For the example I used, a 100mF cap = .1uF ,
  15. Hotwaterwizard, I may be interested in a couple. I am looking for 2 crossover inductors of 1mH and 1 of .22mH. Are the inductors in your crossovers eather value -or- do they have a part number that I can look up? oldgrandpainmi
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