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Help designing a remote controlled cupboard lock

Asheekay

New Member
You will need to consider, the person could just hold the door open.
If its something that is ok to access by the person at home your sending the unlock code to, then there is really no reason to just not install a normal lock and give that person a key?

Its a fun project and all I guess but not very functional, and not very secure at that.
Those latch style locks are easily bypassed with a thin plastic shim. The problem with bolt latches tho is the door needs to be shut before it can lock.
It's not that I'm paranoid about the security of the cupboard. As I stated in the original / first post, the cupboard contains general household items (used once or twice daily). I have given the key to the missus ... who always misplaces it and then there's a search operation in 3 rooms of the house to find it.

Wait ... I think I can make a complete comedy serial based on the concept :p

Back to topic: now to find a suitable amplifier (if sound amps are not to be used), then decide whether to use the vibrator motor connection for pure dc or rectify the ringing signal. The rectifier part is easy. 4 diodes and it's done.

How can I build a suitable amplifier for it? Any help?
 

Nigel Goodwin

Super Moderator
Most Helpful Member
How can I build a suitable amplifier for it? Any help?
Your major mistake through out this thread has been looking for an 'amplifier', you're confusing yourself because of it, what you're looking for is more a 'switch' than an 'amplifier', and there have been numerous examples posted and linked throughout this thread.
 

rjenkinsgb

Well-Known Member
Most Helpful Member
Back to topic: now to find a suitable amplifier (if sound amps are not to be used), then decide whether to use the vibrator motor connection for pure dc or rectify the ringing signal. The rectifier part is easy. 4 diodes and it's done.

How can I build a suitable amplifier for it? Any help?
See my post (#31) and start just with the rectifier stage from the circuit I linked to, to find out what voltage you get from that.

What you use after that depends on what the phone produces!
 

shortbus=

Well-Known Member
As I stated in the original / first post, the cupboard contains general household items (used once or twice daily). I have given the key to the missus
Why are you locking them up? There is something your holding back on this. If the things are something she needs many times a day, shouldn't she be in charge of them?
 

narkeleptk

Active Member
It's not really anyone's business why he wants to lock the door.
Isn't it tho, For the people who are considering helping or not? Do they not have the right to ask why, just as much as the TS has to ask how?
Perhaps shortbus= is not comfortable to help for something that seems nefarious and is concerned . Seems reasonable to me. TS has no obligation to respond if he feels uncomfortable in doing so. So whats the problem?


To be clear, I am not calling the TS or what he is doing nefarious.
I am simply implying that if someone did feel something fishy going on in any thread, they had a right to ask why.
 
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Mickster

Well-Known Member
Most Helpful Member
I have been thinking about some of the questions and answers in this thread, along with conclusions that may have been jumped to.
Perhaps there might have been some stereotyping, for whatever reason, or a reluctance to reveal the cupboard contents due to strong opinions from other member's viewpoints....dunno what goes on inside other member's heads, but I can see a use for something like this in my own home.

My wife and daughter (step) try to eat as healthy as possible, whilst I am fortunate enough to be able to eat what I want, without gaining more than a few pounds, and as such, we have vastly different diets. In my 400 sq/ft garage/workshop/tinker-space, I have a fridge, a freezer, a kettle, and a microwave. Since I spend so much time in there, the fridge and freezer are stocked with soft drinks & beers, snacks, and microwavable stuff that can be 'dinged' whilst I am plodding away with my projects.

The problem is that I don't tend to get the cheapest microwave stuff, or snacks etc., but rather go for the more healthier options with the least amount of ingredients, but which still taste good. And the fact that they taste good and are much more convenient than preparing & cooking raw foods, is quite the temptation for the wife and daughter to 'cheat' on their diets. Simply knowing that the stuff is there, and that they can easily get to it, is enough.

It's sometimes a pain to know what you have in the fridge/freezer, and look forward to making it, then come home to find that it's gone, whilst the culprits are kicking themselves for taking and eating it. I've lost count of the amount of times I have been told to hide stuff, which they have bought, so that they can't get to it and have a binge until it's all gone. There is no portion control, but plenty of remorse afterwards.

So, I can see the benefit of being able to remotely control access to a room/cupboard/pantry/fridge/freezer, without having to know exactly why this particular OP wants to do so.

Regards.

BTW, if any member is not comfortable with the content of a particular thread, they have the option of reporting it, and/or just not participating. AFAICS, there is nothing within this thread that violates the TOS of ETO.
 

gophert

Well-Known Member
Most Helpful Member
So let's avoid the question.
It's not really anyone's business why he wants to lock the door.
I, like narkeleptk seem to disagree with at blind enthusiasm to solve problems exactly as asked. "Why" is as reasonable as any other question.

Isn't it tho, For the people who are considering helping or not? Do they not have the right to ask why, just as much as the TS has to ask how?
Perhaps shortbus= is not comfortable to help for something that seems nefarious and is concerned . Seems reasonable to me. TS has no obligation to respond if he feels uncomfortable in doing so. So whats the problem?
This is true. Also, challenging the OP with non-electronic solutions (as shortbus= Has been) can certainly help guide the OP to an optimal solution - nefarious or not. One member telling another member we should not be asking why is completely bull crap. Asking "why" is a great way to wipe out the non-sense or misconceptions of how technology works or insures we are not solving an ill-conceived solution and really solving a problem.
 

Mickster

Well-Known Member
Most Helpful Member
If the OP was not from some sandy place, would there be the same scrutiny?
Just sayin....
 

Mickster

Well-Known Member
Most Helpful Member
To add to the above, it would be pure folly, in this day and age, to solicit advice from an open forum, trying to produce something like this:

IED.jpg

especially considering that Snowden blew the whistle on the tools available to the spooks back in 2013. Imagine what they have now...

Maybe it's time to dial down the paranoia and try to help OP?
 

DrG

Active Member
If the OP was not from some sandy place, would there be the same scrutiny?
Just sayin....
I don't know why you are saying that and, frankly, I think that "just saying" is a very weak way of speaking your mind. I have seen people argue or be contentious about almost everything on forums (never me, of course bwahahahahah). I don't think that there is any "scrutiny". It is very common to ask the questions that boil down to "what are you doing" and "why are you doing it". I see that all the time and I can't believe that any regular forum user would disagree. It is just the nature of communicating.

What is a little unusual is how long it took the OP to fully explain what he was trying to do and why. Who after the first post understood that his idea was to keep one phone on inside the cupboard all the time? I sure did not, but maybe you did - did you?

He has an answer for why every suggestion representing more common (and more reasonable in my view) solutions is unacceptable - good for him. He wants to do it his way....but he has also been given links to circuits and repeatedly had them explained...so spell it out for me, where is all this scrutiny based on the sand content of a country? I see a bunch of people trying to help with an unusual implementation.

After reading 50 posts on this, does it not occur to you that a combination lock would be a simpler solution? I did not suggest it because I am confident that there would be a reason why that would not work for him either. So let him do it his way....but I swear, if his cupboard starts calling my cupboard at all hours of the night, I am going to be steamed!

Plus, he called me "senior man" :)

Oh no no. Not at all, senior man.
 

Pommie

Well-Known Member
Most Helpful Member
it would be pure folly, in this day and age, to solicit advice from an open forum, trying to produce something like this:
But, isn't that exactly what has been requested. However, as many solutions have been provided and are freely available on the web suggests the OP doesn't have the necessary skills to progress.

Mike.
 

Mickster

Well-Known Member
Most Helpful Member
This thread was initially doing fine, although the OP appeared to not grasp what some of the replies were suggesting, versus his/her (mis)conceptions about opamps and such. Long distance comms, remote operation of an actuator, rectifying speaker output from low current through a diode bridge, opamps, transistors as a switch (offered by Nigel) and all that...
Where it took a turn, IMO, was the inquisition regarding why the cupboard needed to be locked, and the usage of the word 'nefarious', from a couple of members.
WTF is that about?
I think some are reading far too much into this, and coming up with 2+2=5
 

Mickster

Well-Known Member
Most Helpful Member
I don't know why you are saying that and, frankly, I think that "just saying" is a very weak way of speaking your mind.
You're welcome to your opinion, as am I. But you did not address the fact that if the OP was home-grown in the US, from Texas as an example, there may have likely been less scrutiny. ;)

What is a little unusual is how long it took the OP to fully explain what he was trying to do and why. Who after the first post understood that his idea was to keep one phone on inside the cupboard all the time? I sure did not, but maybe you did - did you?
From his 1st post:
I finally came up with the idea of somehow controlling it with a cellphone.
Note the somehow?
It was not implicitly stated that the phone would be inside the cupboard. Why did you come to that assumption?


He has an answer for why every suggestion representing more common (and more reasonable in my view) solutions is unacceptable - good for him. He wants to do it his way....but he has also been given links to circuits and repeatedly had them explained...so spell it out for me, where is all this scrutiny based on the sand content of a country? I see a bunch of people trying to help with an unusual implementation.
[/QUOTE}

There were a bunch of deleted posts...one can wonder what the contents of the said posts were, but there remains a semblance of restraint and professionalism here:
So let's avoid the question.
It's not really anyone's business why he wants to lock the door.
After reading 50 posts on this, does it not occur to you that a combination lock would be a simpler solution? I did not suggest it because I am confident that there would be a reason why that would not work for him either. So let him do it his way....but I swear, if his cupboard starts calling my cupboard at all hours of the night, I am going to be steamed!

Plus, he called me "senior man" :)
Sure, a combo lock could work, but once the other party knows the combination, that cookie jar will be empty.

Perhaps 'senior man' is a mark of respect? Different cultures and all....
 

DrG

Active Member
Look, I don't want to get into a big deal about this, but honestly, I think you jumped to a conclusion about others. You are the only one who defined, with an example, of what nefarious action could be underfoot.... shortbus= could have been thinking that he wanted to keep a pr0n collection locked up....or maybe it's a drug operation...or maybe it is pretty much what he says...that he had tried giving a key to his wife and she keeps losing it.

OK, I can buy that, but a combination lock would seem to solve that pretty easily and ["Sure, a combo lock could work, but once the other party knows the combination, that cookie jar will be empty."] he could change the combination and if she forgot it, she could call him and he could tell her. Problem solved. But he would reject that solution (as did you).

He wants to build it and build it his way and he has said so clearly - but he does not know how. That raises some questions as a natural process that takes place on the forum - if you don't know how (after circuits and methodology has been presented), maybe a different approach that you do understand is in order...AND resisting other approaches, can raise questions.

Note the somehow?
It was not implicitly stated that the phone would be inside the cupboard. Why did you come to that assumption?
I came to that understanding, not an assumption, when he spelled it out in post #13.....especially when he bolded the word inside....even my "senior eyes" could see it.

You're welcome to your opinion, as am I. But you did not address the fact that if the OP was home-grown in the US, from Texas as an example, there may have likely been less scrutiny. ;)
Do you understand how somebody might question the appropriateness of your example at this particular time given what has recently happened in Texas?

If you want the last word, have at it, but, I think I made my point and yes, it is my opinion. It is also my opinion that I should lighten up because this is simply not worth arguing further.
 

gophert

Well-Known Member
Most Helpful Member
Where it took a turn, IMO, was the inquisition regarding why the cupboard needed to be locked, and the usage of the word 'nefarious', from a couple of members.
Mister, You were literally the first person to use the word "nefarious" and also the first person to mention sand.
 
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dougy83

Well-Known Member
Most of the circuits provided so far are a little complex for a beginner. If the vibration motor output is used, all that is needed is a resistor, transistor and diode to interface to the solenoid. The solenoid will pulse as per the original motor pulsing; if this is an issue (though I doubt it should be), an extra diode and capacitor can be added on the input to extend the ON time.

119875
This image is modified version of one found on image search.
 

Mickster

Well-Known Member
Most Helpful Member
Mister, You were literally the first person to use the word "nefarious" and also the first person to mention sand.
Look at post 47 - nefarious....look at your own use of nefarious in post 49....
Ho hum.
 

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