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16  Forum 2005-2010 (read only) / Interfacing / Re: Hi Power HBridge, DC Motor on: February 23, 2009, 02:07:38 pm
It's impossible to fit this L298 on a normal breadboard... how can you manage this? Do I need to solder 20 wires?
17  Forum 2005-2010 (read only) / Interfacing / Re: PoE with Arduino on: March 11, 2009, 04:55:19 pm
Follower said it right, there are power injectors that runs on Cat5 cables. They are used for Hiperlan antennas which allows to run only one cable for data and power to the antenna (which is an active device).
Have a look on these
http://eidusa.com/Electronics_Kits_PoE_injector.htm
18  Forum 2005-2010 (read only) / Interfacing / Re: Recording Audio Sample Data on: January 11, 2009, 09:43:10 am
wouldn't be easier to do this with a multichannel audio card?
It's quite computational and bandwidth heavy.
Not only the serial port is terribly slow, but maybe you introduce too much delays between the channels, and it would make it difficult to increase the accuracy of your project.
19  Forum 2005-2010 (read only) / Interfacing / Re: Arduino with old Laptop LCD? on: February 10, 2009, 08:43:32 pm
Thank you for the reply Mem.
I looked at that adapters for a CarPC project some years ago, but the price/capacity factor was bad at that time.
There's the write cycles problem, seems Windows is able to wear a CF card in less than a month, must use a special read-only IDE driver from XP embedded or use Linux.
Unfortunately I already did all the sw optimization on W2K smiley-sad
20  Forum 2005-2010 (read only) / Interfacing / Re: Arduino with old Laptop LCD? on: February 10, 2009, 03:11:42 pm
I'm already doing this exact thing.. bought an asus laptop on ebay for 60 euros... it has a nice 12.1" TFT panel, PII 233, 128M ram. Enough for a stripped down Windows 2000.
There's only one USB port, so probably it makes sense to drive the Arduino with the serial port.
Too bad the HD is so noisy.. probably I need to spend the whole laptop value for a new HD haha
21  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 18, 2009, 07:23:46 am
Great Wortelsoft! I was exactly looking at bobbitsbox store before you told me! The guy reply very quickly to the email and the fact you bought from him makes me more confident.

Are these mini soldering station just a toy? ZD-927 16 euros


I would use it for attaching SMD components to the stripboard with small wires.

Or is it preferable this one? ZD-937 45 euros
http://www.china-zhongdi.com/tcss01.htm

I'd like to have something better than ultracheap solder, but not as expensive as Weller, Ersa ones...
22  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 18, 2009, 05:04:10 am
Smaller caps added... this thing is going to be an arsenal!
23  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 17, 2009, 08:06:59 pm
Ran, I share your point of view, I'll look on the italian section if there are any upcoming events or fairs.

However I'm building a network of sensors and motors with some Arduinos in my house, and probably I'll use 30-40 of those caps just for decoupling purposes. As I'm saving some money buying part of the list through eBay, I could afford even those 47uF caps.
The biggest issue when you buy online are shipping costs, you can only recover them by placing big orders from time to time, otherwise it's cheaper to go to the local shop even if it charges you 0.30$ for a cap or resistor smiley
24  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 17, 2009, 01:32:59 pm
Thank you for the tip!

I'm doing another shopping list on a british eBay seller.
They sell 50x 0.1uF 25V 20% +/- disc ceramic capacitor for 1.12 euros



The ones I've found on RS are these, and 100 of them cost 7.8 euros.

They have X7R dielectric, 100V, 10% +/- and works till 125°C



Of course the latter seem to have better quality, I need these for decoupling on 5-12V supplies.. Can the cheaper ones work or better forget them?
25  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 17, 2009, 10:47:11 am
Yeah I already bought one breadboard for experiments...

I always worked on proto board like you Osgeld, but for unknown reason it's easier to find Vero board on eBay. Maybe because of its British roots.

Do circuits made on Vero board occupy more space than prototype boards? I have this impression, but maybe with a bit of clever engineering the footprint is the same
26  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 17, 2009, 08:57:52 am
X Pluggy: yeah now I understand, with these tracks and track cutter it save you to solder wires between pins sometimes. Seems better than individual solder pads, right?

X Ran Talbott: yeah I should find those assortment packs.

The 100uF 25V caps are sold in 25 packages and cost 2 euros per package, that's why I added 100x, so I would have a good inventory

I switch to 2N2222 because it can handle more current than 2N3904 and it's just a little more expensive

Added 10 LM324 and 10 7805, they are everywhere smiley-grin

I've seen you can find many good deals on eBay sources, however the task of comparing takes up a lot of time, and if the orders are scattered the shipping costs doesn't make them cheap anymore:(
27  Forum 2005-2010 (read only) / Interfacing / Re: what basic stuff to buy for a electronic hobbyist on: December 16, 2009, 10:28:40 am
Thank you Grant for your tips!


Quote
- stripboard if they sell it (the stuff that's basically a breadboard you can solder to)
Yeah I'm going to buy some stripboard at the local store, as I couldn't understand on RS if they have stripboards with a grid of isolated contacts. It seeems they have grouped them in rows or three by three.

Quote
- various sensors (temperature ones are super cheap, so are photocells)
I agree. Which ones did you order?

Quote
- potentiometers
I ordered a few 100kOhm carbon potentiometers that can handle 50mW.
Quote
- wire
Is it ok telephony wire? It's made of solid copper inside. I'm buying also Verowire for SMD applications
Quote
- heat shrink tubing
I added a polyolefin one, 3mm internal diameter, 3:1 shrinking ratio. However it's quite expensive, 7.93 euros for 10 meters!
Quote
- 5v regulator (LM7805)
yeah those are like onion and garlic smiley-grin

what about transistors and capacitors? Are they fine the ones I choose?

28  Forum 2005-2010 (read only) / Interfacing / what basic stuff to buy for a electronic hobbyist on: December 16, 2009, 07:29:42 am
Hello friends,
I'm putting a big order to RS as there is a 20% discount for the first order. what stuff is a must for a electronic hobbyist? I put this list by watching most popular circuits on Playground and other sites:
- 100x resistors of various values (2R, 100R, 1kR, 2k2R, what else?)
- 100x schottky rectifiers 1N5817
- 250x fast rectifier diodes 1N4937 can it work as replacement of 1N4004 and 1N4148? according to what I read, a fast diode is always better than I slow one, and it's marginally more expensive)
- 50x 2N3904 transistor (is it better to replace them with 2N2222?)
- 100x BC327-25 0.8A transistors (are these redundant?)
- 100x ceramic X7R 100nF 25V caps
- 100x electrolytic 100uF 25V caps
- 50x electrolytic 470uF 25V caps (are they useful for the L298 driven 2A 12V DC motors?)
- 1x solder wire 60/40 Sn/Pb 1 mm 2.5% flux 250 grams
-5x 2N7000 Mosfet transistors (don't remember why I put them)
- 10x TIP102 (seems useful to power beefy things)
Any suggestions for cheap optoisolators? I would power them at 5V and they have to simulate key presses on remote control buttons, so the load would be small. Probably quad channel optos are better for fit in tight space.
29  Forum 2005-2010 (read only) / Interfacing / Re: Replicate BenQ IR remote on: February 21, 2009, 07:18:15 am
Have a look at an IR catching sketch I've written. It might be useful.

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1234957671

Plus I'm trying to catch air conditioner codes, but I'm in trouble due to my non-existent know-how, anyone with some suggestions?
I'll share the codes once I'll be able to capture them.
30  Forum 2005-2010 (read only) / Interfacing / Re: detect presence of stationary persons on: January 12, 2010, 06:14:39 pm
yes you're right AWOL, Arduino can handle I2C as well as serial TTL, but I was looking for a solution both portable (with an Arduino and a LCD display), and fixed (directly connected to a PC, right under the monitor)

I found an even better explaination on the same site of a IR emitter and detector more accurate even on ambient light, it uses the same technique for remote controllers
http://www.ikalogic.com/ir_prox_sensors_40khz.php
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