1 hour ago, sixwheeledbeast said:

Not any more...

 

well...

16 minutes ago, Gabs said:

Thanks, I'll have a look at that, schematic looks pretty big though, more complex than the Logic 4

 

Yarp but at least it has a full description of what's going on, which is pretty cool.

28 minutes ago, norman said:

Not sure, nothing old and ancient. A few components maybe. 

 

That's good  I have decided that I will probably build one of the transistor panels from Ron's site, so the components will help me there, thanks  

26 minutes ago, datadiffusion said:

 

Yarp but at least it has a full description of what's going on, which is pretty cool.

Yeah, it is. Shame Velleman don't make alarm kits, they mainly do things to do with lighting, so not as good. 

40 minutes ago, Gabs said:

 

That's bad that you were accused of buying it, but it also says it was better than anything the teacher was expecting.

 

IMHO the school was a f'kin zoo, the pupils would have been better going straight to the workplace (or prison)

 

Apart from the alarm which I think was GSCE.... CDT memories

 

a) Teacher did'nt like the smell of old spice as it reminded thing of someone dieing from cancer - que 30 kids bathing in old spice aftershave.

 

b) I nailed a load of text books to the work benches, open cover wack in a big clout nail though the book, close cover.

 

I must have done 3 or 4 terms of that's all I can recall

16 minutes ago, MrHappy said:

 

IMHO the school was a f'kin zoo, the pupils would have been better going straight to the workplace (or prison)

 

Apart from the alarm which I think was GSCE.... CDT memories

 

a) Teacher did'nt like the smell of old spice as it reminded thing of someone dieing from cancer - que 30 kids bathing in old spice aftershave.

 

b) I nailed a load of text books to the work benches, open cover wack in a big clout nail though the book, close cover.

 

I must have done 3 or 4 terms of that's all I can recall

Sounds very reminiscent of my school, that I have just left. I took product design as a GCSE, but was never given the task to do anything as exciting as make my own alarm panel. Do you have any pictures of the alarm panel that you made? I'd be interested to see  Sounds like a funny thing to do, although it would ruin the books   

This question brought back some memories. I started playing with alarms when I was about 5 years old, started with disassembling a Yellow AND Black Bike Siren that made Police, Ambulance and fire sounds(Anyone remember these?). Being a bit of a hoarder, I still have bits of it. If you are new to electronics, then 555 timers are a great starting point. 556 is a dual version. Also LMC555 and TS555 are CMOS low power versions, so you can use batteries and they will last ages, if you get the circuit right.

Your other friend in discrete logic is the HEX Schmitt Trigger CD40106B. You can make timers, clocks, latches, sirens and lots more with these.

However, In today's world, you really need to be looking at uC like Atmel & PICs. You can buy an Arduino Micro Pro with a ATmega32U4 for under £5 and has enough processing power to sink a small battleship. At the DIY level, you would need very few parts to build a good alarm system, you can add a £3 ESP8266 to it, and you would have a Wifi enabled system.(But you will need to get good at coding and that's a good skill to have.) On a professional level, alarm systems have a little more to their design than just logic.

Most alarms today, used ADC's on there I/O and measure the circuit resistance to be able to detect Tamper, Alarm and Faults. Also components like EMI Filters, ESD and Surge Suppressors. Watchdog and Current Monitoring. On top of this is a whole load of Firmware, Software and Testing. Hope this helps.

 

9 hours ago, QSXS said:

started with disassembling a Yellow AND Black Bike Siren that made Police, Ambulance and fire sounds(Anyone remember these?).

 

Yep had one much to the neighbours hatred!

On 23/08/2017 at 16:46, Gabs said:

Yeah, it is. Shame Velleman don't make alarm kits, they mainly do things to do with lighting, so not as good. 

 

They've lost their way a bit, tried to be all about home automation but even most geeks just want stuff that works out of the box like Hue and Nest,

but then again no money in plain old kits any more

1 hour ago, datadiffusion said:

 

 like Hue and Nest,

 

Did they ever find Linda? 

No, but in 1998 backpackers on an obscure trail in Nicuragua were certain she was living there using the name 'Arreglada' in a remote community.

 

(Well, it seems the Spanish translation of 'made up' wasn't quite the meaning I was looking for...)

Edited August 25, 20178 yr by datadiffusion