Components

From London Hackspace Wiki
Revision as of 18:17, 28 May 2013 by Sci (talk | contribs)

The Hackspace carries a range of electronic (and other) components in stock. As a rule, members can use anything for free, as long as the cost is less than £1. However, if you're using more than £5-£10 worth of components a month, we'd appreciate a donation to cover those costs.

Purchasing

Please include a link to the item, preferably from Farnell, or it won't be ordered.

If you're a member of the space we'll happily order components for you and take advantage of bulk discounts/free shipping. If the component you request is cheap, we may order more than you need and bring it into stock in the space (if that's the case, then it's free as above).

Requests

  • Positive photo resist spray @rapid (free del over £35)
  • Copperboard for PCBs, e.g. [1] or Plain copper clad board @rapid (free del over £35)
  • Bits for the Oki PS-900 soldering station. PHT or SFV series should fit, and be hot enough for toxic-flux lead-free solder.
  • Stripboard, e.g. [2] unless there are cheaper options.
  • chocolate blocks (just ran out)
  • 200 x 2.5mm Cable Ties Delivered
  • NPN transistors (ONE LEFT), atm we stock BC547BG
  • NPN transistors (ONE LEFT). There was a bag marked 2N3904. I think that's a reasonable Farnell part to replace it with.
  • Low Power MosFETs [3]
  • 16MHz crystals (farnell)
  • Arduinos (we should probably get these from Earthshine, but our budget is a bit tight to stretch to them currently -Russ)
  • Miniature trimming potentiometers
    • 10K
    • 100K
    • I have put a selection of multiturn trimpots in a translucent plastic compartment box, currently on top of the component drawers in the main room - artag.
  • 4093 (four NAND Schmitt Triggers in one chip, useful for e.g. polyphonic square wave oscillators) (now UK stock)
  • 4017B ("decade counter"/10-step counter, useful for sequencers) (now UK stock)
  • 4050N level shifter
  • MCP23008 I2C IO expander
  • 555 and 556 timers. These are generally useful, we should always keep a few in stock.

MCUs (ATTiny)

This section added by Daveb who is looking for more info...
see ATMEL's AVR and AVR32 - Quick Reference Guide for useful info.

ATTiny rather than an ATMEGA as it is smaller and lots cheaper or would use an arduino or similar. ATTiny rather than other MCUs for good free tool (GCC etc) support.


Doing searches on Farnell reveals lots of choices, with big price breaks (~40%) for 10 and (~20%) for 100. Price seems to roughly scale with pin count or maybe chip size.. but there are anomalies. It is worth picking a chip and buying a few. But how to choose the chip??

Points that matter to me..

  • enough RAM for interrupt vectors, global state variables, C stack, local variables and interrupt stack
  • excess code space for diagnostic code

Prototyping

  • a few excess pins to allow for in-crcuit reprogramming and debugging (which i think means dont use MOSI,MISO,SCLK or RESET in the application)

An 8 pin dip has 2 pins available to the app (4 debug plus vcc and gnd), while a 14 pin dip has 8 app pins? Four times the app space for under 2x the size:)

in the farnell catalogue at moment i see some standouts.. These are all 8kflash, 512byte ram parts.

  • Not in stock - ATTiny84A-PU 14 DIP, 1.8 to 5.5v, at upto 20Mhz, ADC with 1x, 20x prescale, £1.90(units), 1.39(10s), 1.28(100s)
  • ATTiny 85-20PU 8 DIP, 2.7 to 5.5v, at upto 20 Mhz, £2.36(units), 1.36(10s), 1.14(100s)
  • ATTiny861A-PU 20 DIP, 1.8 to 5.5v, upto 20Mhz, 3PWM, ADC with 1x, 8x, 20x and 32x prescaler :) £2.10, 1.72, 1.48

I like this prescaler, can see it simplifiying some designs.

The part that started my investigation - only 1k flash and 64bytes of ram - one 8 bit counter and no prescaler for the ADC.

--- In stock now :)

  • 1x attiny85-10pu 1.8v to 5.5v, 10MHz (after I took 1)
  • 1x attiny13-20pu

Personal requests

AntLoom

wyan:

daveb:

  • Raspberry PI - to be available from Farnell... would be great to run hacking courses for these, as they are very affordable, and capable and low power (green)!

Links Needed

Please help by finding an appropriate link for the following.

  • new tips for the general soldering irons! (Not at space so can't check models, if this matters)
  • "brass sponge" for cleaning soldering iron tips.[4][5][6]
  • A couple of stiff brushes - to make cleanup around MIll and Lathe easier. Perhaps with some chain to tie them to the table.
  • LEDs (varying, some good bright ones) +1 (we have loads of basic red/green/yellow etc ones)
    • you can get LEDs dirt cheap off ebay. i bought 500 blue LEDs for under 7 quid a little while ago. if you want to go with a more reliable brand, green LEDs red LEDs blue LEDs bicolour LEDs found after a quick price check between rapid and RS. i haven't worked out how to use farnell's website yet so i can't comment on their prices.-alecjw
  • 12V 3A solid-state relay
  • solid-core cable (RGBYKW) and multicore

Tools and equipment

See the Wishlist page.

Some tools we could regard as consumables; get cheap ones and replace them frequently. E.g.:

  • screw drivers

Tool bits and pieces

Recently retired/thrown away

  • spade-drills which had side of the spade drill broken sized 8, 10, 12 and 22 (2011/04)
  • Down to the last hacksaw iron blade (2011/04) - 410 length
  • Down to the last Pendulum Jigsaw saws of the non-T shape saws (2011/04)

Consumables

We're running low on:

  • Logic chips. I think the 74HCT series is a reasonable place to start, but I'm not an expert here.
  • Some banaplugs or already wired up banaplug wires in the usual colours and length.
  • dark blue multicore wire Akki14 06:57, 29 May 2012 (UTC)
  • Heat shrink (bought some its on top of the component wall shelves - need more)
  • Masking tape


See also: Inventory#Stocked components.

Fasteners

The drawers of nuts and bolts are maintained by Artag. Please contact if you have requests.

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