Posts posted by windoze killa
If you are trying to produce a 5V supply and you can't use a 7805 because you only have a 5V input then why not just use that 5V supply.
Most of the system would be run using microcontrollers. You would have to write the code to suit. Basically you would send a request to each car and time how long it takes to get a response. From this you can calculate the distance. The ID would be part of the response.
It acts like a small inductor in some cases.
I missed this post before. Not quite sure hore you can make this statement. A small chip of metal film with 0 ohms would have such an insignificant inductance it would be useless. About the only way I could see this happening is if it was a wire wound 0 ohm resistor
OK you got me where can you buy zero
You could also use an optocoupler.
6" shouldn't be a problem so long as you aren't trying to do it over 50'. Reverse parking sensors on cars are ultrasonic and they are pretty rough in design. So a PC based decoder system should be easy.
We use 0 ohm SMD resistors all the time. They are mainly used as links. We design the boards so there are different configurations available. The resistors are placed to select different options.
I worked on 10KW HF transmitters for years and it never affected me, me, me, me,........
If you use the correct type of soldering iron set to the correct temperature, prepare and clean the pad and component, apply liquid flux and don't be on the joint for more than 3 seconds then there is no need for a heatsink clip. These will just suck heat away from the joint and actually cause a bad joint. If you have the temperature of the iron such that it over comes the effect of the heatsink to allow you to do a good joint you will be overheating you component worse than if you do it properly.
Proper tools and proper technique is everything when it comes to soldering. Another rule of thumb for soldering tips is to chose a tip width that is about 2/3 the width of the pad you are trying to solder.
Remember these simple rules. (probably can be applied to everything in life)
Cleanliness is next to godliness.
Practice makes perfect.
Your best mate is not an expert in everything. You don't go to a Dr to find out how to fix your car so don't ask a plumber how to solder electronics. (nothing against Drs or plumbers) (except for the way they charge)
Sounds like a micro might be the easiest for this job.
I would assume you are going to do all this with some PC or micro. If this is the case then you could track as many cars as you would like. You would just have to give each one an ID number and poll the system to check for each car in turn. All this can be done in fractions of seconds.
The other advantage of ultrasonics is it is less suseptible to losing signal if the trancducer get dirty. If you got dirt on an IR diode it would be useless until you removed it.
There are a few deciaml to binary/BCD chips available.
Have a look at http://pdf1.alldatasheet.com/datasheet-pdf/view/27380/TI/SN74147N.html
Sure, RF's influence in human's health still not determined. Who knows.....
But one thing is, if I have a child, I will not use any RF devices near him/her.
There is also some similar product to bluetooth, like zigbee. But I don't think it will be another technology trend.
I am waiting for UWB wireless USB, where I think in the following few years, it will be a very hot topic.
Does this mean you will stop using your computer???? It probably radiates more RF than a bluetooth device. There is so much radiation floating around these days. All the power wires running through your house and out in the street.
There are also some areas in Tasmania over heer in OZ that are using power lines (the big ones outside) for telephone and internet. Got the phone companies running scared.
How about ultrasonic transducers. You can have a couple on the car so you get 360 degree coverage. Place about 4 transducers around you driveway (one in each corner). If you can produce a timed pulse from the car you can measure the time it takes to be received at each of the recievers and be able to calculate the distance from each and the speed of travel.
Its the multicore one that I use. Works well but should really only be used at a minimum for reguvenating your tips. Say every half hour or so. Too often people forget to clean it off before doing a joint.
See if you can get hold of a pyrometer and check the tip temp.
Another method of checking tip temp is to grab a piece of HMP solder (High Melting Point). Load the tip up with normal 60/40 solder. Place the HMP across the tip. At 300C it should melt through in 1 second. If it is melting in less time (like instantly) then it is way too hot.
Thank you for the inputs guys
windoze killa, I do exactly what you said but in the soldering time when the tip is cleaned it turns gray in a matter of seconds.
About the iron not being good enough, I totally disagree! Sure it's not a soldering station but from what I gather it's one of the good one in the simple range. Both the iron & the tip are quite expensive compared to similar products. What is annoying is that I have used other cheaper irons before & they have done a better job with no maintenance. So much for the iron clad tips! Or probably I'm doing something wrong
try replacing the TIP32 with a relay. Another option, replace the 1K resistor with a 470R. This would turn the TIP32 on harder. But I think the relay would be the best shot.
Yes, but your talking digital. Digital is a different story... yes, it'll work there. I was talking power analog design.
Do you mean this software!!!
The board we just finished has 4 DC-DC SMPS on it for powering the the various components. It also has built in GPS and radio modems. It also has 7 analog inputs with filtering. I am not sure why power analog design would be any different. If you are talking RF power then yes, you may need to do a little bit of manual routing but you initial statement refered to DC-DC convertors.
I am not sure what a tinning block is but I assume it is something like a small tin on solder impregnated flux that is sold here as tip cleaner and tinner. Personally all I do is after each joint or when I put the iron back on the stand is to load the tip up with normal solder so it is completely covered. Just prior to doing the next joint wipe it clean and it will be spotless. One important thing to remember is that there is one thing more important than flux..... CLEANLINESS. Never try to solder with a dirty tip ALWAYS wipe it clean before each joint.
Also I noticed that the iron you are using is a constant temp iron. This is not the best thing to use on a PCB. Solder has a melting point of around 275C and the temperature of the iron should be maintained at about 300C to allow for the drop in temp when it is applied to the joint. I would guess that the iron you are using would be around 400C which may result in dull and brittle joints. It is well worth the investment of a temperature controlled iron. In Oz we get these from around $200 (~75GBP).
Also 3.45 for a tip is pretty cheap. The ones I am using are $30 and the desoldering ones are $45.
Are you kidding? I ALWAYS use auto-router. Analog, Digital, and Mixed-Design. You must not put together very complicated circuits if you manual route all of your Analog boards. ERC and DRC eliminate any problems that you might encounter. Netlist tells you if anything is missing. If there ever IS a problem, the few traces you might go back and re-run are much less time consuming than manual routing an entire board design. If I ever caught one of my Engineers manual routing an entire board layout, he would be looking for another job. That's MY time wasted.
I agree totally. I could never imagine manually routing the 4 layer processor boards we design. We do some manual cleaning up at the end but it would take us months. There is also a heap of analog stuff on these boards too. The power of programs like Altium DXP make it soooooo easy. Just have to make sure your schematic and your design rules are correct and away you go.
compare to 900mhz or 2.4ghz radio modems
Can someone design a PCB for this schematic?? (The dotted cap. is ment to be a 10uF elec. with a dual pot. in series (one for each amp) and to be connected to pin 1 not ground and the 2.5M is the volume) The amp type i'll be using is the LM380N. Thanks
This seems a very simple design. Why not have a go at it yourself? There are plenty of progs out there to help you.
in Electronics chit chat
Without going into deep detail FR4 is the fire retardent level. FR4 is the most common higher quality type. FR2 is used in cheaper consumer type products.
The HASL is basically tinned tracks. The other 2 are electro deposited gold or silver coatings. Much more expensive.