sixwheeledbeast

It's not about buying it tho, it's about what you can learn from making it. Many of the questions Gabs has asked are about reverse engineering and trying to understand what and why, I think that's a good thing. Practical engineering skills seem to be at a low across all fields, I'd imagine many of the employers here will be thinking Gabs could make a better engineer than some they have had on the books for years.

All systems are different, manufacturers will have there own protocols to suit there kit. Galaxy is a standard 485 bus for example, some maybe clock and data or Wiegand derived like the majority of access control, there are many more ways it's all down to the manufacturer. I suppose I have a fairly broad knowledge of a few things computing and electronics being one, some from school and college but a lot self taught. They have always my thing. Back in the days of C&G 1851, data transmission methods where part of the security system exam, not sure if this is still the case. I certainly have never done anything near a professional layout or designed panel but built a good few different circuits on stripboard in my time. What you can learn now with the relative cost of SBC's like Arduino and RPi is a lot more is based on GPIO and code, over the logic with discretes and IC's that I started on. I can only suggest you start basic adding functionality as you go on, if that be in logic gates or whatever code you choose. Make a sensor trigger a sounder. Then make able to be armed and disarmed. Then eventually work up to security of the transmission and tamper protection. Here is a link you may find useful about the way a keypad would work from my post above for example http://www.circuitbasics.com/how-to-set-up-a-keypad-on-an-arduino/ As you can see the computing power of an SBC is many times greater that of the Accenta you have on the bench so it's quite different practically.

Ah yes you are correct about the tamper loop, although the theory is still correct. Have a look into NRZ serial transmission for other benefits of having the line high all the time. Also think about what could happen if there was an intermittent short on the multi cored cable for example. Transmitting decimal numbers via a type of pulsing binary is very inefficient. Your too young to remember how long it took to dial 999 on a pulse phone... You can send a hex value in a nibble, for example this would cover all 15 keys no problem, but imagine an easier ways using rows and columns which keypads generally are. As an example, divide your keypad into col (1-3) and row (1-5). that's 3x5 each axis (We will start counting at 1 here not 0). Send binary X, binary Y and a check and/or stop bit, all can be done with binary in a bytes worth of data. Key 0 001 001 1 0 Key 1 001 010 1 0 ... key 7 010 011 0 1 ... Key Prog 011 100 0 1 Key Set 011 101 1 0 All the keys would be sent in the same amount of time as sending an 8 via pulse. Using BCD you could likely make that smaller again, the lesser amount of bits needed to transmit to get the message over the quicker the communication.

Having never attacked an Accenta with a scope before I am just theorising, however... On a Accenta you have one signal line for data transmission therefore the transmission is serial. As you say there are no separate Clock and Data lines to avoid data collision but what's to say a single non-zero return (NRZ) signal cannot be two way? You could still transfer signals asymmetrically, maybe down to encoding for example, you could have a stop (handover) bit. The last bit on the scope images seems similar so this maybe the handshake bit for the reply or even the actual handover of the supply. Both will need the ability to drive 5V signals to each other, although I would imagine the keypad will supply it most of the time. That way if the voltage is missing (hence using NRZ) for a period of time the keypad could be declined offline and tampered. If you think about it these non-LCD basic alarm keypads are fairly dumb, they sit and wait for input so in most cases the messages to be sent towards the panel are call and response (the response changing/updating the display with data from panel). The only time the panel would need to call the keypad into action (send data the keypads way) would be in an alarm situation, hmm I wonder what that sound wire could also be used for...

I fail to see the difference between a remote and app for controlling the TV. In fact I would say it's more convenient to have an IR remote that can stay in the room and not have to jump through account registration, privacy policy and biometrics tripe to setup a new TV. As for the lights, I see point in having different themes and modes for a large house so something like Lutron makes sense. In reality you need lights for occupancy and lights for presence either of these can be done without a Smart app as I posted above. In using OpenHAB you have no concerns of privacy leakage via third parties, I would say that's worth the setup time, I agree that many of the public would disagree however that's up to them. It's supply and demand with these smart devices, if Amazon/Google/Whoever make a product that is easy and anyone can use, then that is a larger consumer base to obtain and sell analytical data from. This allows them to make new product to keep demand thriving. Lazy is the wrong way to look at it IMO. Automation should be a network suite of tools for efficiency, not the height of laziness. At this point the term "smart-*" is far from smart.

Be a good idea to have it checked over if it's hasn't been looked at in years. Battery and possibly PSU will be shot if it's never been serviced. Don't want it waking all the neighbours up at 3am. You can change the user code yourself if you can enter the code to get into the menu.

Kinda makes me think this isn't UK. I'd say smoke screen system is a good way forward.

More expensive than a half decent sounder from SW?

Point being, I think you need to look at the bigger picture.

Consider the security exploits found in these smart devices on a daily basis, then consider they are connected to your security system... Consumer grade boxes that plug into the internet shouldn't be trusted with the keys to your security systems, it proves a single point of failure. Security is about layers. CCTV stuff I fit is from trade only wholesalers. Being able to have a look at your house is of little use when your nowhere near site. Are you going to watch this app 24/7, or just show people down the pub? Good quality reliable and correctly installed CCTV can be nice to have, but not worth cutting the budget on the other security first is my point here. This is where a risk assessment done by someone knowledgable is worth it's salt. Any decent installer can look at the property and assess what you need, rather than just chuck tat boxes on the wall which serve at best as a mild deterrent.

When was the alarm last serviced? Have you replaced the standby battery in the control panel recently? It may seem to arm/disarm fine but without operational checks you may not know until it fails to operate.

I have explained the best way forward. Replacing your bell would be a waste of time and energy even if you can find a like for like replacement.

That type of bell hasn't been manufactured in many decades. Replace for an SAB of your choosing you may find a model with the aesthetics your looking for. If you need help with the wiring upload a picture of the panel end terminals and we can try and point you in the right direction. https://www.securitywarehouse.co.uk/catalog/intruder-alarm-c-36/sounders-c-36_45/

Forget all that keyfob and Google Home rubbish, have yourself some quotes for a decent wired alarm fitted properly. You could potentially wire it yourself to keep cost down if you approve this with the installer first. Consider the deterrent factor of a external sounder with an approved company on. As for CCTV I personally avoid both Dahua and Hik, very often CCTV is not fit for purpose on many domestics, better to spend more on the intruder and physical security first IMO.

Wouldn't provide me with much confidence. NVM could be on the way out. I am all for maintaining a fully working system but if your getting problems at that age it's time to consider controls replacement.

Seems odd to have an error on Z12 if you have no expander cards on the system (4 zones)

You can fit G3 gear but you can't make it conform to G3.

If it doesn't charge the battery I would consider the panel as not operational, it's one of the main functions that would be checked on a annual service. The panel has done it's job, proping it up with another supply will only create more issues down the line. Have the controls replaced and a full system check while your at it. SLA standby batteries last around 4 years and the external sounder battery may likely be shot if not replaced since installation.

Cisco HP Netgear Draytek... I'd expect to be looking around 230 for a Netgear without fibre ports more for the others. If it doesn't need any features then Netgear would do, most are managed at that size.

It's all relative. I went out to someone last week with a 2 year old Yale thing fitted by a spark that now will not support it for her. I explained the pros and cons, it's booked in for fitting a wired system after Christmas.

Most Pyronix boxes of all eras have the need some tweaking with the box tamper spring/leaf somehow.

If it sounded outside the lid opened.

If it's a "Texecom" box one solid light indicates a fault. It may not be a Texecom one, however possibly a good idea to have your system checked over if it hasn't been done.

Not very helpful posting a picture of something that's not yours when asking for help... Good luck with your Agility certainly not something I would fit, if the above system was yours i probably keep it instead.

Yes to fully decommission a system you will have to get up to the external sounder. Looks like like the panel and possibly bell has been recently swapped, going from the colour of the plastic, the iconic keys, the hold-off working and the paint over where the original panel was. Does the current system work? What would you replace it with?