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Everything posted by oldgrandpainmi

  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
  16. Kasamiko, Thanks for the artical. It is the same basic idea I have used for NiCad's for years. (Charge a cap and discharge it to the battery). But you have to remind me about the capacitors. They are listed (for example) 100mf and 10nf. I know this is not what they actually are, as a 100 millifarad cap won't fit on this PCB and a 10 nanofarad cap is unreal, so I ask, is it actually 100uF and 10 pF? It is stated elseware in a different thread, but I am running out the door for work. I am also curious to see if the wire wound inductors can be hand wound? Have any idea? I would rather try this than to spend $50-100 every other year for batterys for my boat. If I could discharge an auto battery like I deep cell, I'd save a lot of $$ every year!!!! indulis: This is not necessarily true!!! I have had auto and deep-cell batterys (I have one now) that will charge to 90% and discharge after 1/2 hour thru a typical load. I think a "Zapper" will work to rejuvinate this one. I have thrown out batterys that start with 0vdc and after 3 hours, can't reach 50% voltage. I believe this is the type of problem you speak of. I see SO MANY battery's for sale for $5 that it MAY be worth building this circuit just to see if 50% of them can be rejuvenated. It then would be worth it. I see the same thing said about NiCad's. "If they can't hold a charge, then replace them!" This is wrong!!! A NiCad "Zapper" can and will zap 50%-75% back to life.(95%+ of origonal capacity) You have to zap individual cells in a multi-cell pack, but it is cheaper than paying $165 for this laptop battery or %$250 for the laptop I just pitched!!!! I know this for fact, as I used to do it for friend and relatives. The biggest problem is that 25%-50% of the zapped batterys will get destroyed internally, but when you can save a few dozen, it makes it worth it!!! oldgrandpainmi
  17. Hello all. I understand the difference between a standard lead/acid automotive battery versis a deep cell lead/acid battery. What I would like to know is the actual difference between the corresponding chargers. I run deep cells while fishing, and am aware that using a standard charger will not work correctly and you shouldn't charge a deep cell on an automobile (jumper cables). Is there a circuit available for a typical 2/15/100 automatic charger? (2a slow charge, 15a fast charge, 100a start) Building one is out of the question, as it is much cheaper to buy than build, so the circuit would be for my reference. I also would like to know if there are any problems trying to charge 3 or 4 deep cells on a charger at once? (parrellel hook-up) Lasty, is there a way to rejuvinate lead/acid battery's, much like rejuvinating NiCad's?? (NiCad Zapper) Any ideas? oldgrandpainmi
  18. Mares, I am hoping that "tapers" are the same thing as a tap. My opinion is that if you are designing a mechanical "adaptor" for a tap, go to a machinest forum. They specialize in this subject and are as helpful as these guys are with electronic questions in this forum. oldgrandpainmi
  19. For sake of discussion only? The EASIEST way to increase the range is to change the antenna!!! As a ham operator, an antenna is called "the poor man's amplifier", regardless of output power. Here's why: If your antenna has a 3db gain your ERP (Effective Rated Power) is about 2x the amp output (5w in, 10x out). If you attach a 10db antenna, you get 10x the input power. I was able to build a "Quaggi" antenna (combo cubical and yagi) to produce a 14db gain antenna, which gave my 5w handheld 2m radio (144mHz) a ERP of about 60watts). I was able to talk to different repeaters in countys 30-50 miles away. When the conditions were right, I was able to Akron, Ohio, from Pontiac, MI. (CB'ers called it "skip") This antenna is way too big for portable use, bit the theroy is still the same. If you can build or buy a high gain antenna for your rig, you can achieve the same output as the higher distance rig. Besides antenna's, check the frequency difference between the rig's. You may find that there is a difference between them. My 10 meter mobile ham rig can talk to Europe on 10 watts, where my 2 meter handheld can't talk more than 25 miles, with manufacturer's antenna's. I hear people who run QRP rigs (less than 10w) on 20 meters, from around the world. Modifying your output power, on the frequency you are using, MAY get you in trouble if caught. This is why I becam a ham. The options to modify and use rigs is more allowable because of the frequency's used and the license I hold. And depending on the frequency I use, I can legally run 200-1500 watts maximum output power. (add a 10db antenna to a 1500 watt amp and your ERP is now 15,000 watts) Hope this helps, since it is for discussion purposes.
  20. Hello all, I didn't read the individual schematics, but the key here is "the maximum RF output power". The FCC states that anything that transmitts RF over 500mW output power must be approved, for private or public use, regardless of frequency. (I can find my FCC-Part 95- rules and regs manual if necessary). Personally, if you build ANYTHING that doesn't bother anyone else, except within the confines of your property, it SHOULD be ok to use. The FCC just wants that inspection and approval fee. An old Ham radio operator, oldgrandpainmi
  21. Kain, In short, No. (over simplified-----) Basicly, regardless of type, ROM's are just that- Read Only Memory. You supply an address, and the data is what you have programmed into that address. If there is a point in the rom that you do not want to use, or "don't care" what it has, don't use it. There MAY be packages where there is a pin or two that may have a "don't care" situation, I think durring the programming of the EEPROM there is an input or two that sit's in a "don't care" situation, but that condition does not exist durring normal operation. oldgrandpainmi
  22. MP, I honestly don't remember my Dremmel speed rating. I have it put away right now. (Had back surgery last year and haven't dug alot of my stuff out yet.) As far as your statement about carbide -vs- HSS, yep! If you are ANYTHING more than a hobbiest, carbide is the way to go. I'll even say if you are a hobbiest with A LOT of drilling to do, that go carbide. But if you only have small PCB's with limited number of holes, then HSS is my choice. If you break one, then you are only out a buck or so. Besides, as I stated, with HSS, I break them anyway to achive the 1/4" lengths. Even with numbered carbide bits in a dremmel with a press, bits break. As a hobbiest, I can justify $5 for 4 bits to do 1-2 small PCB's. I can't justify $20-$30 for the same bits, especially if the only way to get them is mail-order, to do such a low run of PCB's. If I could justify spending that much $$ for things I may only use once or twice a year, I'd buy my stuff off of the shelf and bypass the construction steps, or, have them etched and drilled for me. It is a personal decision based on $$ available. That is why I drive a Chevy Pick-up and not the Lamborgini I have always wanted!!! :) oldgrandpainmi
  23. MP, As far as "buying -vs- building"--- maybe! I get a lot of scrap parts in my job. except for a few parts, I may be able to build cheaper. I don't know until I look at a schematic. I am considering building an analog ESR meter that I know is cheaper to build than buy. Yeah, as far as square -vs- sine, sine, sine for electronics gear, but square is ok for emergency lighting and camping. OGPIM
  24. MP, Although I can't show this, I can guess: If there is a circuit where the ESR of the cap is critical, it would be different between the voltage ratings, even though the cap's value is the same. Even caps with the same rating and voltage, from the same batch, can vary in ESR. How's that as a guess? oldgrandpainmi
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