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MP
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Posts posted by MP
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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
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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 -
Thanks very much for all the detailed info.
So if you want to vary the voltage, you use a voltage divider with a POT in series with a resistor.
If you want to vary the amperes, you just use just a POT in series in the circuit.
So about a battery, how does a battery vary the current but not the voltage or varying the voltage without varying the current. Like a car battery is only about 14 volts, but it has hundreds of amps?
Not exactly. Your resistors are still going to limit the current. You just have two branches instead of one.
MP
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sema pcb ve gerekli bilgiler dosyada
http://www.hemenpaylas.com/download/717081/gevvUSB_Pic_Programmer.rar.html
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
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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
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You also have to keep in mind the resistance of the load after the voltage passes the voltage divider network. Here are a couple of links that might help you understand a voltage divider better:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/voldiv.html
http://www.doctronics.co.uk/voltage.htm#what
MP -
You can't see an LED display outdoors in the sunshine. But an LCD display is fine in the sunshine.
You can't see either one well in the sunlight. It is the backlight that helps you see the LCD display. The black segment LED and black segment LCD displays both are hard to see in sunlight without a light background. Perhaps you just need a backlight. Perhaps a replacement display with white background. Again, who knows how to help without a schematic or data on what you are using. All I see here is a lot of debate of LED vs. LCD.
nametc3: Where is your information? Some designs are easy to convert and some are not.
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Yep. Depends on what he has. Hope we can see a schematic.
MP -
Are you sure you didn't post this backwards? LED will normally be brighter outdoors than LCD. If it is black LED, perhaps you want to go to the brighter red LEDs.
Like ante said, you will have to post the schematic before successful changes to the circuit are possible.
MP -
If you have a 10 amp supply, it does not mean your projects will use 10 amps. They will only take what they need. However, you should take precaution to have some limiting feature whether it is a 10 amp or 5 amp supply.
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Yes, as you put it, you are just off in space somewhere talking to yourself. It willl not work as a replacement. Better to come up with the bucks for the original in this case.
MP -
Hi frankwas, Welcome to Electronics-lab!
The power amp in your link can run on 25 to 30 volts. This transformer only gives you 25 volts. That is why it is not maximum spec. Most amplifiers need a bipolar supply. Note that this one gives you 2 X 25 volts. This means it is a 50V center-tapped transformer. You want +/-30V, or 60V, center-tapped, provided the power transistors can handle it. If you know which power transistors are used, you should look at the data sheet. You want to make sure error in your mains connection does not take the transistors above the maximum spec.
Also, note that the amplifier will only use what is needed in terms of amperage, so if you allow for some headroom in the way of amperage, you will be ok. This is a common mistake in making homebrew amplifiers. If you do not have enough amperage, it does not matter how many volts are at the secondary of the transformer.
Hope this gets you on your way.
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Always post a link to the project you are requesting information about.
It makes it easier for others to take a quick look.
MP -
Here are some links that might interest you jean-noel:
http://geek.scorpiorising.ca/windingtransformers.html
http://www.shinrock.com/Audio-Transformers/technicaldata.html
http://www.allaboutcircuits.com/vol_2/chpt_9/5.html
MP -
You could also use a 7809 with resistors added like on a 317 for adjustment above the 9 volt mark since you do not need voltage lower than 9 VDC.
MP
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in Electronic Projects Design/Ideas
Posted
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