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Everything posted by Omni

  1. Buy an old C64 and load-in SAM... ;D SAM, what a marvel for its time! http://members.tripod.com/the-cbm-files/speak/
  2. Omni


    Hehe, $1700.00 to kill a bug? :o Cheap advice, use the bottom of your shoe... ;D
  3. What voltage is required at the output to power the device?
  4. The above is noted on the documentation provied with the item but i have yet to see it hold-up in court. Every case i viewed where an individual purchased an item and shared it with a friend was never judged illegal. Remember, the above is where the "gray area" appears, the battle is decided in a court of law and the expense can be overwhelming. Common sense is the key factor, selling a copy is completely illegal! Downloading a copy is probably also illegal since you do not know where the original came from; very subjective!
  5. I agree with audioguru, a non-transformer method for an inverter is basically for lower current devices. Although, i provided a link below that will convert 12VDC- 230VAC (300W) i am skeptical as to the longevity of the inverter along with what may occur in the event of a sag... http://www.tantronics.co.uk/acatalog/DC_to_AC_Power_Inverters.html Circuit below: http://www.aaroncake.net/circuits/inverter.asp Final note: Use precaution with the above circuit and read the directions provided with the project! :o
  6. The inrush current on a heavily loaded motor can easily cause an arc flash when switched in, i have noted it many times. Generally, under the above condition a CB will trip but during the latter time an arc is present. Obviously, the majority of time an arc flash is noted when a load is switched out. Additionally, the issue concerning an arc flash must be addressed and corrected since contact properties will degrade in a non-linear manner. The specification pertaining to the relay along with the current demand (potential) present at the contacts is the major issue. Take some time and read the NEC, you may learn something... ;)
  7. I see no fault in sharing. Example: Suppose i purchase a wood design used for a corner arch, i take the arch and lay it onto another piece of common wood and draw around the purchased arch. After the above is performed i make 10 more to complete my project. When completed with the original arch i give it to a friend; FREE! Remember, copyright material cases must follow a very fine line to be illegal. Similar to software: I spend $150.00 for a program (it is now my program), i copy the program which is the original store purchased item and provide a copy to a good friend (sharing). I believe the main problem is when a person copies (material) and then tries to sell the copy; the latter is illegal. I do not see anything wrong in sharing with friends.
  8. Haha, good fun! The link you provided reminded me of the web sites in the early 80s when i was the bomb! My computer: Commodore 64 with a 1200 baud modem! Sadly, i cannot remember the ISP but it was worthless... :-\
  9. Trace density along with the use of surface mount components require a more controlled (faster) process for etching. MP provided a few good reasons for the latter in which i agree. However, if you plan to use the typical size components and the PCB layout is common (open trace density) the method you are currently using is perfect. Ferric Chloride that is heated along with continual movement (bubble) accelerate the etching process. -Omni
  10. MP, I mean no disrespect concerning my statement. The majority of hobbyist use the typical component size, i myself avoid using surface mount which would require more detail concerning PCB design along with the control method of etching. Truthfully, i never expect to duplicate a printed circuit board manufacturer nor would i waste the money in trying. Being able to make a decent PCB along with a pseudo tinning process is more than enough. The few flaws that appear in the copper is a part of the process that give's the board a home made character. ;) Like an old wooden floor that has a few squeaks. ;D
  11. Use the below links to gain an understanding as to how a counter operates. Next, purchase a breadboard along with a variety of connection wires. Finally, start experimenting! http://www.doctronics.co.uk/4510.htm http://www3.telus.net/chemelec/Projects/Counter-UD/Counter-UD.htm http://www.ibiblio.org/obp/electricCircuits/Digital/DIGI_11.html
  12. A pull-up/down resistor is generally applied to an unused gate input since leaving the input open can introduce outside noise (electrical) causing the input to change state. Whenever in doubt read the data sheet concerning the gate/IC you are using concerning the latter.
  13. Keron, The links provided (schematics/circuits) are used as another alternative. Perhaps, in some way you may notice a section of the particular circuit that you can apply within your design. The added capacitance on the output of the 7805 is a simple filtering method used on many regulator designs, the latter is used primarily to reduce stray noise when a long source lead (V) is used. Additionally, the added capacitance provides a stable output for the regulator (78xx).
  14. Keron, I located a few circuits on the net that may work in your application. A slight modification concerning any of the latter circuits may be necessary but the concept appear's proven regarding the designs. Take a day and view the links below, see if you can make one work in your application. http://www.uoguelph.ca/~antoon/circ/sensor1.htm http://www.elecdesign.com/Articles/ArticleID/9137/9137.html http://www.uoguelph.ca/~antoon/circ/sensor3.htm http://www.zen22142.zen.co.uk/Circuits/Alarm/water_lev_alm.htm :)
  15. 1. Slightly oversize a pyrex glass tray to the copper clad board. 2. Pour some common Ferric Chloride in the tray and place your board in the latter solution. 3. Every 20 min using your hand lift one side and allow the ferric to wave over the board. 4. After 1 hour your board should be complete (depending on size). 5. Using tongs remove board and flush with water, clean resist from PCB. 6. Pour the Ferric back into its bottle and use on the next project! 7. Clean tray with water and allow the faucet to run for 45 sec - min (flush pipes). The above process has been used since the dawn of time, why try to reinvent the wheel. Furthermore, when making a PCB at home remember it is an enjoyable hobby, time is not a big concern... :)
  16. The DC source (battery) is a simple test to determine if rapidly switching your CMOS logic will operate properly without a false trigger. Once the above is determined you will know if the DC power supply you are using is the culprit. Arc flash across a relay is somewhat common because of the large motor load that is being switched in, generally you would purchase a relay for the required specification. When purchasing the relay make sure to specify the MAX voltage/Current, factor in the NEC requirement and ask for the latter with arc supression etc... Example: 230V/10A pump motor : 10 *1.25% = 12.5A Sensitivity concerning the sensor/s you plan to use is another variable that requires experimenting. Generally, a sensor requires an amplification stage to provide a level sufficient for TTL/CMOS, use your knowledge of transistor theory (basic) to determine the output required. I cannot design a sensor circuit without having the sensor available since the latter does require some bench experimenting. You appear to have a good knowledge of electronics and can perform the above.
  17. Vary 100K trimpot to adjust speed of flash etc...
  18. Hi Keron, Practically, all IC circuits draw a very small amount of currrent, the latter can cause problems since a power supply when turned off will slowly discharge since current consumption of your circuit is not enough to pull it to ground fast enough. When you rapidly turn your power supply ON/OFF the source voltage is never able to find ground fast enough, the slow decay during ON/OFF is still at a potential to activate your low current circuit. Remember, filtering capacitors and how they store a charge... A good way to bring the source voltage to ZERO when turned off is to provide adequate isolation, use the below circuit to OPEN the rail voltage when turned OFF. The circuit is proven and will allow you to rapidly enable your source supply ON/OFF without any problems. However, do not add more capacitance to the bottom section of the circuit, keep the small filtering cap at 10uf; one does not need a lot of filtering for a relay! Furthermore, DO NOT disregard the circuit in replacement for a load resistor to pull the source supply to ground, the latter is counter-productive and will only create more current and heat! The above is a dilemma with most on-board power supplies, the circuit presented is a very good work around that will address the issue without any drawback! Finally, i am not completely sure as to how you are using the MOV in your circuit since i believe the problem is associate with the DC level (voltage) powering the CMOS etc... Another way to mimic the above without building the (pictured) circuit is to power your circuit (CMOS) with a small DC battery with an in-line switch. Rapidly, switch the DC on/off in rapid sucession and see if your issue is noted. ;) -Omni
  19. Hi Keron, Actually, for the use you specified your design would be more suited. The type i mentioned is for a particular purpose. I used a float switch (waterproof) along with a relay, 555, 2N2222A and a small assortment of passive components. Once the water level in the sump (tank) enabled the float switch the 555 in conjunction with a variable delay provided an ON time to a driver/relay which would empty the tank. The relay is a DPDT using one half to enable the contact to the pump when initiated, the other half of the relay provides a throughput from an external charger to the DC source battery for charging etc... Furthermore, a few LEDs depict status concerning pump enable along with DC (activated) in the event of a power outage.
  20. Actually, the circuit should have provision for both AC and DC operation. I am not sure as to the use your pump is designed for... Example: Take for instance the typical basement sump that is used when a heavy downpour occurs. Generally, a home will have a perimeter area drain around the inner walls of the basement, water will collect within the latter and through pitch of the pipe eventually end in the sump container, after the level of water reaches a determined amount a pump float switch will remove the water to the drain or outside. The above is a good concept but most designers/engineers rarely think outside of the box... Remember, with a heavy downpour lightning is usually noticed, the latter can easily cause a loss of AC power! :o Sadly, the sump is powered by AC, which in turn is now non-functional, the result = overflow... :-[ A good design will have a 12V (tractor battery) for DC backup in the event AC fails. Additionally, during the time the AC is operating it is trickle charging the battery. :) I designed the above circuit 10 years ago... -Omni
  21. http://www.justradios.com/uFnFpF.html Ditto ;)
  22. Become a doctor, the World is always full of sick people... Additionally, you do not have to be a surgeon, just a simple ear - nose & throat doctor! Plus, once you have graduated join a few in a group building, you can pick the days you like to work (3 days a week). A simple basic doctor can generally make $500K a year! Listen, do not let the so-called hype of how difficult it is to be a doctor prevent you from attending. I have a doctor friend who graduated Notre Dame and i would not bring my dog to him... -Omni
  23. Obviously, you have enough voltage at the base (24V) and the length to the LEDs (100') max is well within the tolerance of your supply voltage. Consider using an adequate guage wire (16AWG) and place a small regulator circuit at each interval (length). Using a regulator at each node 50', 75' & 100' will regulate the voltage to the desired amount required by the LEDs. The regulator does not need to be too technical, a simple Zener (1W) along with a proper sized load resistor will work. Furthermore, perform a test on the ground to make sure your interval regulators will operate properly. Example: Stretch the max length of wire on the ground and at each interval place a regulator, the latter will allow an easy painless way of testing your setup. Twist the wire for more integrity along with a clean installation and use a decent wire (teflon coated/silver). Remember, the NEC does not even begin to calculate a voltage drop until 100' in reached. However, in your case the max would actually be 200' since you must also factor in the return length. Furthermore, a calculation is not really necessary since you are 100% above the required voltage at maximum length. Footnote: I remember awhile back designing advanced accelerators for the Trans-Atlantic cable. Most common people believe solid state amplifiers are placed on the ocean floor to amplify the communication signals since the length is extremely long. In truth the latest engineering design consisted of specifically placed 3 meter lengths of doped Rare Earth erbium (fiber optic) that would continually accelerate the transmission. Rare Earth Erbium is located deep within the Earth and when doped with the proper elements is highly light sensitive!
  24. I am not sure as to the overall current demand of the project but you can design a small regulator circuit using a few components to perform a precise voltage. The 1N4730 is a 3.9V Zener, i provided a link below to calculate the required current limiter resistor. Sadly, when powering a project using batteries it is usually always advisable to design the circuit using a source voltage that does not require any type of loading since battery drain is produced via the regulator circuit. The latter is somewhat counter-productive. Perhaps, you can provide more detail concerning your circuit? http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/zenereg.html
  25. MP, Actually, the process you described has been around a long time. Although, the concept of photo sensitive copper clad boards will make the job much easier. I remember having to use a resist/developer in a darkroom! The method you described will allow much less overall error since it does not require a precise temperature for fusing (PnP) etc... I have been using PnP and the overall method is a little loose since a variety of variables can make the outcome frustrating. However, i am trying to sharpen my skill with the procedure. Perhaps, if i start to become too frustrated i will resort to the method you outlined. Furthermore, i believe your view has a lot less margin of error on both the material and user intervention. Thank you, Omni
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