Comments directed at novices...from a novice
rjo_
Posts: 1,825
Hi Guys (and Gals)
1. I must be a half a step ahead of someone... so, if that happens to be you. Let me give you some advice.
When you get a circuit that works... don't just tear your bread board apart. You will eventually forget what you think you know... and the circuit
that could refresh your memory... will be gone. Get some kind of PCB... and immediately transfer your bread board creation... then put the name of your Spin file on the back.
I do this myself after visiting a manufacturer and seeing a football field sized wall... with every little prototype that the manufacturer had ever produced for the previous 100 years... Yes, there are some companies out there that have been around that long.
2. When you need to remember something... get out the PCB copy of your circuit and refresh yourself.
3. Don't expect this to work every time. I am about to refresh my thread on transistors and 96 bit pixels... but before I do, let me explain why the thread exists. I made a circuit... a remote controlled video switcher. It worked... I committed it to a RadioShack board. When I wanted to use the same transistor for my 96 bit pixel as I had for this board, I went to my reference circuit... plopped it in. AND IT DIDN"T WORK.
I didn't know why... I spent days reading and re-reading, still I couldn't figure it out. Finally, I downloaded the spec sheet for the transistor ... and I had the sucker in backwards. Why it worked for my video circuit, I haven't a clue.
4. Absolutely the most flexible PCB for Prop work is from http://gadgetgangster.com/ Have a look. If you are serious about your work... you need some of those boards.... get them while they are hot.
Rich
1. I must be a half a step ahead of someone... so, if that happens to be you. Let me give you some advice.
When you get a circuit that works... don't just tear your bread board apart. You will eventually forget what you think you know... and the circuit
that could refresh your memory... will be gone. Get some kind of PCB... and immediately transfer your bread board creation... then put the name of your Spin file on the back.
I do this myself after visiting a manufacturer and seeing a football field sized wall... with every little prototype that the manufacturer had ever produced for the previous 100 years... Yes, there are some companies out there that have been around that long.
2. When you need to remember something... get out the PCB copy of your circuit and refresh yourself.
3. Don't expect this to work every time. I am about to refresh my thread on transistors and 96 bit pixels... but before I do, let me explain why the thread exists. I made a circuit... a remote controlled video switcher. It worked... I committed it to a RadioShack board. When I wanted to use the same transistor for my 96 bit pixel as I had for this board, I went to my reference circuit... plopped it in. AND IT DIDN"T WORK.
I didn't know why... I spent days reading and re-reading, still I couldn't figure it out. Finally, I downloaded the spec sheet for the transistor ... and I had the sucker in backwards. Why it worked for my video circuit, I haven't a clue.
4. Absolutely the most flexible PCB for Prop work is from http://gadgetgangster.com/ Have a look. If you are serious about your work... you need some of those boards.... get them while they are hot.
Rich
Comments
I'm a big fan of Solderless Bread Boarding, and here is a tip that I find helpful.
1) Once you have a design working the way you want it on a SBB, transcribe it to a schematic.
2) Re-build your design·from the schematic created from Step #1 on another SBB
3) If all is well you won't need to repeat Step #1.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Beau Schwabe
IC Layout Engineer
Parallax, Inc.
I've learned to force myself to jot things down, even if they seem trivial at the time. It's been a lifesaver, and has saved alot of time in the long run by not having to re-invent the wheel.
Post Edited (Philldapill) : 5/3/2009 6:26:00 AM GMT
www.evernote.com
Eric
After about 10+ flashes I've forgoten what the question was and have to retrack everything.
The only problem with creating the PCB approach is I tend to recycle bits endlessly unless a definite usage is found. Demo boards and programmers aside. She wouldn't let me keep too much "junk" anyway.
I was chatting to a work colegue about 70s and 80s SBCs and what we had done with them and of course never documented anything at all.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
For me, the past is not over yet.
This is where the "Propeller Cookbook" came from.. They were my personal notes, made so that I wouldn't forget things. [noparse]:)[/noparse] I've even grabbed a copy from time to time to remind myself how something hooks up. [noparse]:)[/noparse]
OBC
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
New to the Propeller?
Visit the: The Propeller Pages @ Warranty Void.
An easy thing to do is to take lots of digi photos of projects as you go (as well as taking as many notes as possible) There is an enormous amount of info in a visual aide-memoire, and there are not so many scraps of paper to misplace. This is our lab practice as well : when working on equipment, shoot lots of photos before going in to make changes. It can capture the details that notes alone can't.
Cheers!
Paul Rowntree
I use a program called iView Media Pro to catalog all my photos. Since I take quite a lot of photos I can figure out where I was and what I was doing by sorting the photos by keyword, date or whatever. Of course this fine program was bought by Micro$oft and is now called Expression Media.
So I agree completely, keeping a photo record is a great help. Equally important though is cataloging those photos with keywords so that you can zero in on just what you need. Oh, and make backups!
Rich H
BTW I am N8TV
I know, I looked you up! Not too many Earl's that are Hams in Mountainair, NM
I was traveling through NM a few weeks ago and got on the 2 meter net. Talked with KD4HE briefly, he was talking about some robot that he was making. Do you know him?
Rich H
Post Edited (W9GFO) : 5/3/2009 5:41:42 PM GMT
Beau...
You can lead a horse to water...
Rich
Eagle (and others) is a nice package with tons of library symbols if you have time/patience to learn it and is free with some restrictions. I use a project notebook for keeping track of consulting activity/hours mostly.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
--Steve
Propalyzer: Propeller PC Logic Analyzer
http://forums.parallax.com/showthread.php?p=788230
For photography I keep my GPS tied to my camera so I always have the location and time I took all my pictures at. Important since I take over 50,000 a year. Have not thought of taking pictures of circuit boards for reference sake but will have to start doing that.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
About 18 months ago I was asked to work on a pro bono research project involving photon counting. At the time, I knew next to nothing about electronics but the project seemed insane enough to warrant my full attention, so I quickly put together a circuit based on a few things I had read. It used an ultrafast comparator on a small breadboard and, though I whipped it up in one night and it looked like a little wig of wires, it worked like a charm. Everyone was happy, so I agreed to take on the project and went on to build a larger circuit using a dozen comparators, etc. This time, however, I worked very methodically, took my time, made all the wiring nice and short and very attractive. I was so confident it would all work that I never bothered testing any of the circuits until I was done wiring the entire thing. Problem was, after finishing my breadboard masterpiece, none of it worked. None of the comparators would remain stable. Each squealed and squeaked in its own crazy way.
I spent two weeks trying to figure out what I had done wrong. Finally, I started doing my homework, reading about ultrafast comparators for the first time. And - duh - what did I find? First of all, using such comparators on a breadboard is a big NO-NO. Second, a ground plane was essential. And third, I was supposed to use low-loss bypass capacitors and not the cheap junk I had started with. At the time, I didn't even know what a ground plane was. Long story short, I switched from breadboards to soldering everything onto protoboards with ground planes, etc. After that, all the circuits worked as they should. Everything was rock solid stable.
So the big question remained: how come my original little wig of wires worked so well? I went back to it and found that if I bent one of the wiggy wires even a little, the comparator would go unstable. If I bent the wire back into position, all was well again. The same was true for several other wires I had looping through the air. Somehow, by some twist of fate, that crazy little wig had tuned things just right and kept the comparator rock solid. Had it not worked so well after one night of kluging, I probably would have never got involved in all this electronics nonsense in the first place. Ah, but alas, here I am. "Believe in God now?" asked one of my colleagues. "Still not sure about God," I answered, "But of the Devil I am certain: he dwells inside a breadboard."