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wireless keyboard encoder
markallen
Hello All.
I'm trying to make a custom wireless interface for a video game I'm making. I'm familiar with using a keyboard encoder, but I wouldn't know how to make one wireless. Does anyone know of a company that sells wireless keyboard encoders, or can point me to somewhere for modifying a non wireless one? Thanks Mark |
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Help with antena enforcement
Gabriel Preda
开云体育??? I get all sorts of noises in my radio... and some radio
stations that I used to listen to won't work any more...
??? Can you give me some help to make my radio better... I'm
only in the seond year of electronics (haven't studied yet the second one...
lol...)
?
Gabriel Preda Web-Site: (new released version 1.5) Web-Master @ E-mail: gabriel_p@... Politehnica University of Bucharest Electronics & Telecomunications Faculty |
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clock help was counting ic's
Nick Graber
开云体育I got myself a 555 timer but im not shure how to
get it down to 1hz or 60hz to base the clock if somone could help me with
finding the values for the 2 resistros and the capacitor the ic I am using
triger from low to high for 1 count. I also had alredy thought I bough some cool
dual 7 seg displays with a common + lead but they are alphanumaric with a common
- lead and I cant seem to find out how to make the dual display, display 12 all
I can get out of if is 11 22 33 44 and I dont see how you could get 12 13 14
exct.
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Nick Graber???
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lm2907 F to V question
Has anyone used one of these?
I am using it as a tachometer and using an induction coil for my sensor. My question is the on the 8 pin version of this IC the pins are tied to ground through a resistor or RC; but the sensor is also tied to my engine ground. I am powering this project with a 9v batt. Should I just tie the neg side of the 9 volt to ground for my IC ground or should I also reference the 9 volt and the IC to the engine ground for the sensor. I am thinking that I might get feed back if I do that. Am I thinking too much? THanks |
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Anyone have an idea if this exists?
Caldwell, Robert E
开云体育Hi, I'm looking for an electric solenoid (I think that what they're called: a cylindrical device that has a piston which pushes when actuated) that is no bigger than 2" in diameter and about 6" height that has the capacity to push 300 lbs of pressure about 1" per stroke at rates maxing out at 30 times a second. Does anyone have an idea where I could begin to find such a device?? Am I asking for the impossible here? Thanks, Rob |
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Re: Shift-register and synchronous counters
--- In Electronics_101@y..., adityan007@y... wrote:
the answer is 11But can you please elaborate more? You see I am new in this world of electronics and unfortunately I have to ask people like yourself to get all the answers. Another question: How can a ring counter be converted to a Johnson counter? countconveyorJonThanks for the support: ascountermany as 1 500 cans. How many flip-flops are required in the circuit to count all the items? |
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Re: Digest Number 75
In a message dated 08/13/2001 2:21:03 AM Pacific Daylight Time,
Electronics_101@... writes: Here is the question: 11 flip-flops, I believe..2^11 is the first power of two greater than 1500. -Chris |
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Re: Shift-register and synchronous counters
the answer is 11
because 2 raise to 11 =2048 but 2 raised to 10=1024 which is less than 1500 aditya n --- In Electronics_101@y..., thecrack@t... wrote: --- In Electronics_101@y..., "Jonathan Luthje" <jluthje@p...> wrote:conveyorCrack-man,Thanks for the support: belt. A pulse is generated each time a can passes a sensor, whichin turn triggers the counter circuit. The counter needed has to countas many as 1 500 cans. How many flip-flops are required in the counter |
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Re: Shift-register and synchronous counters
--- In Electronics_101@y..., "Jonathan Luthje" <jluthje@p...> wrote:
Crack-man,Thanks for the support: Here is the question: A counter is neede to count the number of cans passing on a conveyor belt. A pulse is generated each time a can passes a sensor, which in turn triggers the counter circuit. The counter needed has to count as many as 1 500 cans. How many flip-flops are required in the counter circuit to count all the items? This is the easy one and again thanks for the support. |
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Re: How to make a time delay relay
What I would like to do is have the fan come onwith the compressor and then stay on for 30-60 seconds (doesn't have to be accurate) after the compressor shuts off. The fan is 120vac and draws 1.2 amps. moisture. I would like to make something that will open the valve for a few seconds (2-5) when the compressor starts or when it shuts off. Hi, There are special relays that are made to do exactly what you want. Called 'time delay relays', they come in a variety of types. For delayed off, they often have a knob on the top to set the delay from a second up to several minutes. Get a 'double throw' contact. It has a second set of outputs that will come on when your compressor goes off. You can then use that with an 'interval delay' type relay to open your drain valve for a few seconds. They're usualy not found at your local electronics store, but you might try electrical supply places that sell to the heating and air conditioning trades. Try . At the top of the page, enter "delay relay" in the product search. Most of these things plug into a socket that looks like an old-fashion octal tube base. Those are available with screw terminals for each wire, so construction is fairly easy. Be careful working around 12VAC. _Bill |
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How to make a time delay relay
I'm beyond beginner level, but not too much, so there is where I am
at. I am trying to come up with two things. 1. My air compressor sits in a sound insulated box in my garage. The box has vents and I have a fan the circulates air whenever the compressor runs. What I would like to do is have the fan come on with the compressor and then stay on for 30-60 seconds (doesn't have to be accurate) after the compressor shuts off. The fan is 120vac and draws 1.2 amps. 2. I have a 120vac valve on the bottom of the tank to release any moisture. I would like to make something that will open the valve for a few seconds (2-5) when the compressor starts or when it shuts off. Any thoughts on that? Thanks in advance for any ideas and help. Larry |
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Re: Slowing down voltage
robert wong
开云体育Hi JOn,
?
I? have a LM317 in TO220 package that I intend
to build a 1.5 - 35v?/ 1.5amps variable regulated power supply?for
testing my hobby electronic circuits.?The transformer is 230AC50~/32-0-32v
rated at 3 amps.? Do you have?a circuit that I
can?used???
?
Appreciate help from you and regards.
??
Bob Wong - Singapore
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Re: Slowing down voltage
Jonathan Luthje
Hi,
toggle quoted message
Show quoted text
First - a little more information - at what amperage (current) do you need this voltage? It's reasonably important. There are a couple of ways you can do it, either with a LM317 positive voltage regulator (and a by-pass transistor if you need a higher current), or a Zener Diode / NPN transistor combination. Regards, J0n ----- Original Message -----
From: <ifugeri@...> To: <Electronics_101@...> Sent: Friday, August 10, 2001 10:31 AM Subject: [Electronics_101] Slowing down voltage I need to slow down 12VDC to 4.5VDC, what do I need to accomplish |
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Re: counting ic's
Nick Graber
开云体育ya that does so I do that for 10 and I do that for
6 and do that 3 times and I have a clock but first I am trying to hook a 7seg
led to a bcd to 7seg and cant find out how to do 1 2 3 ~ 10 11 12 and so on
although I can do them 11 22 33 44?after 9 I dont get numbers.
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Re: counting ic's
Hi Nick (and friends)
Following the thread, I see several different parts of the circuit being described, but all on the right track. First, to correct a typo in one of the other replies, 10(base10) in binary should be 1010 (not 0101) a six would be 0110. Decoding that for divide by 6 or divide by 10 is about the way it was described. Once you get all the digits counting and dividing right, the answer to your next question will be to use a BCD to seven segment decoder such as the 7446 or 7448. That will do the translation for the usual square number displays you're use to seeing on clocks. Then again, if this is mostly a learning exercise, we can do the same thing with a whole bunch of gates. Before going into that, or even the dividers, you need to get your input working consistently. You said it was sometimes clocking several times when you push the button on the clock input. This is quite common with mechanical switches. They tend to `bounce'. Usually too fast to see, the spring inside the switch will cause the contacts to strike several times before they settle down. Assuming you have the pull-up resistor on the CP input as recommended in an earlier reply, this is normal and will go away when you add the pulse circuit to get it running on its own. One minor nit in the recommendation to feed it with 5 volt AC. You will want to use a diode to get half-wave DC to the CP input. AC will swing negative on half the cycle and burn up your chip. To square it up a bit, I'd use another gate before the input. This assumes too that you're plugged into the wall to get AC in the first place. I'm guessing you're actually powering this from a battery or small DC power supply. Let's get it simply counting first, and worry about accuracy a bit later. I like the suggestion of using a 555 type clock chip. In it's simplest (monostable) mode, it can sit in between your button and the CP input, so it gives you ONE consistent pulse each time you hit the button. A resistor plus a capacitor set the length of the pulse. After that, hooking its output back to its own input will make it pulse repeatedly. The nice thing here is that depending on the size of the resistor and capacitor, it can be run at any speed from hours-per-pulse up to so-fast-you-can't-see-it. Have Fun, _Bill |
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Re: counting ic's
Jonathan Luthje
开云体育That's the easy bit - just feed the 60Hz into the
clock, then count up to binary 10 (divide by 10), and feed binary bits used to
make 10 (0101), into the inputs of a
dual-input?AND gate IC, and?feed the output of the AND gate into the
reset of that counter. You can also use the AND gate output as a clock pulse,
although since you are using a negative edge trigger you may have to use NAND or
inverted AND gates.
?
Does that make sense?
?
?
JOn ?
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