In the absolute literal sense, nope. But in the real world, there is often a need for a device that can act as an electrical short in PCB circuit applications, something that an auto-insertion or auto-placement machine can handle as if it were a simple resistor. Thus the "zero Ohm" device, a jumper wire with a plastic body for through-hole insertion equipment. A standard size and shape "chip" for SMT applications.Do zero ohm resistors really exist?
No, but I've read a few on both high-end audio and RF transistors. It's enough to make me want to start a wafer fab shop of my own so I can be sure of what I'm getting. These days, we're at the mercy of some pretty unsavory folks in the tech industry, and they don't have much mercy.BTW . Anyone read the Farnell article on counterfeit components?
Is this another joke or is this real? If real, do you have the link?Anyone read the Farnell artice on counterfeit components?
Very real and perhaps the most notorious case ( at least in part blamed on counterfeiting ) was the case of 'exploding electrolytic capacitors' which plagued motherboard manufacturers and others in recent years.Is this another joke or is this real? If real, do you have the link?Anyone read the Farnell artice on counterfeit components?
In my case it was a HP all in one printer fax scanner -an expensive one. I chanced on a report that identified 3 electrolytics on the motherboard that had blown and were causing symptoms the same as I had.'exploding electrolytic capacitors'
Thanks for all the input.[everything deleted]
I bought an 8 pin proto board, but I think I'll still buy the development starter pack AXE091U because of my lack of soldering skills even if I just use the 8 pin chip. I get the feeling it will be nice to know my stuff isn't failing because of a poor soldering attempt. No doubt I'll gain the soldering skills as required.My point on starting out with the smaller chips is, as a beginner to construct a simple project and get it all working is easier with a small chip, then it can be put into use.
Then start the next project and complete that one, this way you will have dedicated circuits for each application and much easier to trouble shoot.
Than as the skill level grows by all means move to the larger chips and start to combine the individual projects into one chip.
At least you know each project was working, this saves a lot of headaches from conflicts in programming when starting out.
Its not as though the smaller chips are wasted as they get recycled back into other projects.
I have nothing against working with the bigger chips but its often much easier to move up then it is to go back.
The amount of things i have used a 08m for is staggering as they are really a cheap great little chip for developing the quick small projects and with the added functions in the 08m2 now many projects that required a larger chip to be used (like for I2C) can now be scaled back to the 08m2 chip.
It is also good to be limited at times on program space as this teaches us to use smarter programming methods and in many cases faster instruction execution.
Soldering skills are something you will pick up and the 08M project board is pretty tough with only a few things to solder. Just make sure things are pushed down when you solder them and you'll find useful guides on beginners soldering using a search engine. Number one rule; don't solder IC's, use a socket. And don't have the IC in the socket when soldering it !I bought an 8 pin proto board, but I think I'll still buy the development starter pack AXE091U because of my lack of soldering skills even if I just use the 8 pin chip. I get the feeling it will be nice to know my stuff isn't failing because of a poor soldering attempt. No doubt I'll gain the soldering skills as required.
temp_address_for_picaxe(at)hotmail.com[stuff deleted]
Not sure how to contact you directly, does this forum support Personal Messaging?
[even more stuff deleted]
Yes - second item on the subheading menu at the top of this pageNot sure how to contact you directly, does this forum support Personal Messaging?
Yes, mostly used as jumpers, but sometimes used to adjust a resistive network.Do zero ohm resistors really exist?
I started off with a 35w iron from Maplin and that worked fine. Antex irons are great and warm up fast for their power but in order to increase efficiency, the tip fits over the element making the element weaker and a backup soldering iron is needed to replace it. Homebase 40w soldering irons run far too hot and will instantly fry any surface mount resistor or de-flux some solder.On soldering irons. Anything over 20 watts is overkill for small soldering. Try an 18W Antex.
Thanks... A more interesting part of this is RoHS parts being sold off as non-RoHS parts - so are ALL RoHS parts inferior to their non-RoHS counterparts then? I thought that only applied to solder.
No, but SOME might be. And no, I have no examplesso are ALL RoHS parts inferior to their non-RoHS counterparts then?
Are you looking at my shopping cart wish list and using the force on me to confirm my purchase? (except the 28X2)Soldering skills are something you will pick up and the 08M project board is pretty tough with only a few things to solder. Just make sure things are pushed down when you solder them and you'll find useful guides on beginners soldering using a search engine. Number one rule; don't solder IC's, use a socket. And don't have the IC in the socket when soldering it !
The AXE091 development board is a good bit of kit and it's what we use within Rev-Ed.
If I was buying an AXE091 for someone I'd probably also include two or three 08M2 and a 20X2, perhaps a 28X2 as well. That should keep them going for some time. I'd suggest starting experiments with the 08M2 and buy more than one because that's the insurance plan if something does go wrong - Like carrying an umbrella prevents rain, having more than one likely means they'll never get damaged, but if you've only got one it will !
Yeah, I run a few computers, and this linux box I tend to use most is from the dark ages. It's bristling with serial portsIf you get really stuck post a message here or send me a PM (private message) through the forum and i will call you and walk you through a few things to get you started.
I am also more than happy to let you work things out for yourself, as often that way you dont forget as you learn at your own pace.
The important question to ask is do you have a serial port on your computer, as the cable you have is for serial only.
If you dont have a serial port you will need a usb to serial cable, these can be costly depending where you get one from, i do have about 10 of them here is you need one cheap and in a hurry and can post it Monday if needed.
I buy them from China in lots of 10 for around $2.00 each and never had one not work.
In general RoHS parts would be considered superior to non-RoHS parts as they won't contain the hazardous substances they seek to avoid.A more interesting part of this is RoHS parts being sold off as non-RoHS parts - so are ALL RoHS parts inferior to their non-RoHS counterparts then? I thought that only applied to solder.
Bellyfeel.
"Little yellow thing" could be a 100 nF 100V capacitor. Do you have any electrical test gear? Suggest you pop in to the likes of Jaycar & check their numerous DMM (Digital Multi Meter) offerings. Some DMMs in the $$ range cover a full swag of V,I,R,F,L,Hz,diode,transistor & temp measurements, and are up to almost anything a home user may need.
Can I get a non-RoHS PICAXE to run at 256MHz?No, but SOME might be. And no, I have no examples
If the first part is true why is the second part also true? It makes no sense. It would be like needing a new approval method for PICAXE chips after an 'internal gang programmer change'.It's not that RoHS parts are inferior to non-RoHS parts just that the approval process is only valid for non-RoHS parts.
You'll get on file. Just only keep the soldering iron on the pad long enough to melt the solder until it stops flowing. If you get ugly-looking spikes, you've kept it on too long. Also, melt the solder on the connection rather than doing it on the soldering iron beforehand and then putting it on the connection.My big plan for tomorrow was to see if I can solder.
The idea of frying a LCD so early in my education is a little daunting
That's exactly it. If the approval stated we had to use a particular version of a chip to be approved we'd have to use that version of the chip, period. We don't have such rigorous and specific approval processes we have to abide by but people putting things in medical equipment, in aircraft and similar almost certainly do.If the first part is true why is the second part also true? It makes no sense. It would be like needing a new approval method for PICAXE chips after an 'internal gang programmer change'.
That's an excellent point.but people putting things in medical equipment, in aircraft and similar almost certainly do.