The resistors R18 and R22 that should have been connected to pin 8 of U4 were mistakenly connected to pin 9. The present versions have been corrected. A minor error on the component layout is that there are two versions of C2, in the upper right and lower left corners - let one of them read C11 instead (they are equal). This is not corrected on the image. Here is the latest schematic by David H Bevel - I have
Click here to download the full size of the above Circuit.
updated the text with his parts numbering (I hope, but I may have missed occasionally!). This schematic, the parts list and the PCB pattern (Full scale at 500 dpi - or a 1:4 version for viewing ) (note that the pattern is seen from the component, NOT the copper side!) and an alternate PCB pattern with less copper etched away, as well as the component layout and the timing diagram are mutually consistent - I am sure. Also, here is a diagram of the connections and a picture of Dave`s version built and ready - Thanks a lot Dave for all the work you`ve done ! Folks, please respect our copyrights. Next in the pipeline - the modification necessary to use a low-voltage stepper motor using 3V supply (and 12v for the control circuit). If this is of interest to you, mail me at nilsolof. carlin@telia. com. This circuit was designed primarily to feed a 5. 25" floppy-disk type stepper, driving a threaded rod, but may be used with other platform designs. It features: I`ve been using an equatorial platform for my 13. 1" and 6" Dobs. I consider the platform a very useful addition - a full GoTo mount can do more, but I think the mechanical complexity is also in another league. It is of course particularly useful for planet studies - not least if you like to show planets to friends and acquaintances, as you do not need to re-position the telescope every minute! However, the full-step circuit I have been using (until I made the circuit...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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