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AQA GCSE Electronic Products

How did people find the exam today?

Personally I thought section B was mostly fine but messed up on section A by not realising I was sketching the wrong idea :mad:

Also made up some rubbish about sound pollution for the burglar alarm question and missed the totally obvious point about battery drain.

I don't imagine enough people take this course to allow an unofficial mark scheme to be made?

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what a load of sh*t
I did the same haha- I wrote that it turns off so that it can be deactivated without ear damage. At least we aren't the only ones!
What answer did you get for the one about the Time High Astable? I got 73.23 or something
I found the exam ok, I decided to do section B first because otherwise I would have spent too long on section A.
what did you do?
I'm an idiot, how did I not say battery drain...
I think I got an A*, found every question to be quite easy but I somehow got the easiest question about the resistor value wrong - put 100 ohms
Original post by adamodactil
I did the same haha- I wrote that it turns off so that it can be deactivated without ear damage. At least we aren't the only ones!
What answer did you get for the one about the Time High Astable? I got 73.23 or something


It was definitley 0.7623
- 10uF is 10x10^(-6) F
(edited 7 years ago)
Original post by Year11Struggles
It was definitley 0.7623
- 10uF is 10x10^(-6) F


Yes it was 0.7623
I almost forgot what the symbol for a bi-coloured LED was
Original post by Year11Struggles
It was definitley 0.7623
- 10uF is 10x10^(-6) F


That's what I got too
Reply 9
Original post by adamodactil
I did the same haha- I wrote that it turns off so that it can be deactivated without ear damage. At least we aren't the only ones!
What answer did you get for the one about the Time High Astable? I got 73.23 or something


Original post by Year11Struggles
I'm an idiot, how did I not say battery drain...
I think I got an A*, found every question to be quite easy but I somehow got the easiest question about the resistor value wrong - put 100 ohms


Done some research and now that I think about it, the loud noise and nuisance thing could be right. Battery drain would only apply if mains was cut off. It's law for them to turn off after a set period of time because they cause a nuisance.

Original post by emilyaves2000
I found the exam ok, I decided to do section B first because otherwise I would have spent too long on section A.
what did you do?


I did the same, always have. Usually works for me but this time I was short of about 10 mins to comfortably finish section A, hence the mess up with the drawings.
I think noise will probably be fine although I decided to put both just in case
Yeah, i got 0.76 and for the resistor value i got 125 ohms
Oh boy :frown: I got 100 for the resistor calculation and 1.2 for the astable one cus i worked out its frequency.

I thought it should be 100 though.
(edited 7 years ago)
Reply 13
Same. Was the preferred value 130 ohms?

(125 and 0.76)
Original post by M451
Same. Was the preferred value 130 ohms?

(125 and 0.76)


Why is it 125? Wasnt i meant to use V=IR?
Reply 15
Original post by James2021
Why is it 125? Wasnt i meant to use V=IR?


I believe input voltage was 4.5V. The LED dropped 2V and pulled 20mA.

R = V / I
R = (4.5-2) / 0.02
R = 125 ohms
Original post by M451
I believe input voltage was 4.5V. The LED dropped 2V and pulled 20mA.

R = V / I
R = (4.5-2) / 0.02
R = 125 ohms


Ah crap. I'm an idiot for not remembering that >.<

The calculation questions always get me because I always make stupid mistakes ....
(edited 7 years ago)
What did you guys put where i asked about the voltage relay and the Darlington driver? I put something for them but i am not sure if they are right.
Yeah I got 130 from the e24 series


Posted from TSR Mobile
Original post by James2021
What did you guys put where i asked about the voltage relay and the Darlington driver? I put something for them but i am not sure if they are right.


Voltage regulator regulates the volatage from 9V to 5V because a PIC micro-controller can only work at 5V

Darlington array is used to anplify the low signals from the microcontroller to high signals when reaching the buzzer

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