MP

Your spacing is 10 mil. You should be fine. MP

The diode was not originally backwards. I should have looked closer after you the two of you told me it was wrong. Datasheet shows that it was in the correct placement. This is why I strongly press on members that we do not make changes unless you are actively bench testing a project. This is the mess that results from it. I think the original author might have re-submitted the schematic since I inquired about it to him. MP

I use 3M transparencies. Hope you get it sorted out. I usually have no problems with traces down to 7 mil. I hate the press and peel stuff. I ask too much from it and end up with too much touch-up afterwards. MP

You are on the right track kachew. All relays list a relay coil resistance. Just use ohm's law. You should come up with the same values as the manufacturer through calculation. MP

No problem! 8) Hope you will share a picture of your finished product with the group when you are done. Good luck! MP

I haven't looked at the schematic for the problem yet. No it has not been changed from the original. I have only asked the original author to get involved. MP

Good. I have notified Kyriakos to correct his schematic and re-post. Sarma, thanks for the correction. Since I was not following this thread, I read your post as variable cap and not varicap. If this schematic does not get corrected in the next month or so, please remind me and we will correct it without the original author's intervention. MP

I have made thousands of boards using transparencies from an inkjet printer. How old is the printer? The old inkjets did not have very good resolution. You can get a new high resolution inkjet for US$50 if you shop around. I use darkest color and highest resolution. I also select transparency from the menu. I have never had to print twice. One thing you might try is to go to the adjustment screen for your printer and fool it into thinking you are not seeing the test spots dark enough. This will cause the printer to go darker. It will be useless for printing on paper, but it will be good for your board transparencies. MP

please post a link to the project. MP

sarma, variable caps are not directional like an electrolytic.It does not matter which direction you connect. However, I do not see one in the project. Are you discussing the project in our project section here?: http://www.electronics-lab.com/projects/rf/020/index.html MP

Herman sent this message to the moderator: >>Thanks for Your offer to help. Do You prefer Eagle format or just a screen dump. Eagle version is 3.55<< I think it is meant for you ante. Best regards all, MP

It all depends upon the motors you are using. If you are using 5 volt motors, you can use 5 volt for all. I have 12 volt motors. This is why I used the 12 volt buss from the power supply for the motors. A PC power supply provides 5 volt and 12 volt. Red to Black is 5 volts and Yellow to Black is 12 volts. It also provides a negative 12 and negative 5 that you will not use. Here is an interesting website that discusses making a power supply from an old PC supply: http://web2.murraystate.edu/andy.batts/ps/POWERSUPPLY.HTM MP

On mine, I actually use the 12 volt for the steppers and the 5 volt for the digital portion of the circuit. Yes, you just connect the wires to the power lines. If you want to add fuses, it is a good idea. I cut a lot of corners on mine becuase I had to build it fast to get a large number of circuit boards drilled before a deadline. Thus, I did not incorporate fuses, limit switches, or a number of other safety parameters. I have never used KCAM, but I have been told by other members that it works well with this project. MP

I thought I would post the basic design block for a current source for those who might not be keeping up with you guys. MP

I didn't mean for you to buy the kit....schematic is in the pdf. Use it for ideas to create your own. MP

V5, This thread was actually started from schematic (b). It is also the most common one used, since the LEDs are more common. There is not a significant difference on these two projects other than the dual LEDs. They both get the same job done. Schematic (b) should be a little more stable since it has a smoothing capacitor across the input. Other members have reported that schematic (a) shows some instability in displaying the numbers. Too sensitive without the cap. Also, go back to reply # 26 in this discussion. This is where discussion of using this chip for an ammeter starts. You will most likely find some information there that will be helpful. I highly recommend that you read all of the replies in this thread. I compiled three different conversations into one thread so that all of the discussions were in the same area. MP

I use a pc power supply with no problems. It actually works much better than the linear one I had previously since it does not generate heat. MP

You should post your schematic and board layout if possible so that you can get more exact help. MP

You do not have to use the exact parts in Eagle as long as the pin out is the same. Otherwise the connections to the IC will all be wrong when you use the original. If you are going to post a bmp, you do not need a lot of resolution or a big size. If you are not sure, post the bmp and see what it looks like. You can always delete the post and start over. MP

Well said, NanOp. MP

Even though your car battery has hundreds of amps capacity, your circuit is only going to use what is needed by the device that is connected to the battery. You do not need current limiting for this purpose. However, if you get a short in the circuit or somethig else happens that starts sucking large amounts of current from the power source, you need to limit the total amount of available current or else you will have a marshmallow roast. Fuses are good protection, but if you have no current limiting, everything will be toast before the fuse does you any good. Thus, to answer your question: A battery does NOT vary the current or the voltage. This must be achieved in your circuit design. Each circuit can be calculated down to a load, measured in ohms. In other words, the complete circuit can be looked at as a resistor. MP

Not exactly. Your resistors are still going to limit the current. You just have two branches instead of one. MP

Gevv, This is an English language forum. Please use English so all members of the forum can understand your post. (Also, microcontroller items can get more exposure in the microcontroller forum) Thank you. MP

This thread isn't about you and your gadgets audioguru. Please allow the subject to get back on track. This is not helpful to nametc3. He is looking for advice on how to modify a circuit. He should post more information to get that help. MP

The formula is in the data sheet. This is the first place you should look. MP