OLD WIRED HOUSE ALARM HELP PLEASE

[Nicetoseeyoutoseeyounice]

After 5 years of not being able to find the key for my house alarm and numerous internet searches I finally managed to locate the key number and purchased a new key. This is an old-ish wired alarm, no key pad or fancy bits, just a key to turn on and off but had been excellent until the key went missing.
I've switched it on and it showing red indicator lights as there being faults. Obviously this bit works. The panic button works, and the outside alarm box is very loud when the panic button is pressed (plastic key to turn this off). There is only one sensor high in the main room and this seems to work as it intermittently flashes 'red' when it senses someone, this is how it has always been.
I've attached some photos, if anyone can help with this I'd really appreciate it otherwise I'm looking at £££££ for a new alarm which I just cannot afford.
OR, am I wasting my time ?
Can anyone see anything that's not quite right, apart from its age.
When the key is turned to switch on there are 'bleeping' sounds, the 'exit fault' lights red and the 'zone two fault' lights red.

 

[sparkymarka]

there’s more than one detector on this ….what else is on the system ….?

 

[Nicetoseeyoutoseeyounice]

Theres nothing else, not visable to me anyways.
Internal doors were replaced, I honestly cant remember if they had those little block box sensors on them but if they did then surely the other half of the sensor would still be attached to the door frame with wiring and there's nothing.
By the way, thank you for at least responding, this is such an old alarm it was a real long shot even posting on here. But, if I can repair or even get repaired then it will be worth it compared to the cost of a new alarm system.

 

[sparkymarka]

May have been concealed contacts in the door frame ….look at the door frame , the magnet would have been in the door

 

[Nicetoseeyoutoseeyounice]

I’ll scrutinise the door frames when I’m home, but having sanded and painted these myself in the past I don’t recall anything being inside the frame, in that, there should have been cable coming out of the doorframe at some point, unless, of course, the previous owner had them buried in the wall. I’ll double check everything.
if there had originally been something like this do you think it can be repaired, not by me, by re adding some extra sensors to a couple of doors.
The front door was also replaced, it’s possible this could have had a sensor, but the whole door and frame were replaced.

 

[Mottie]

3&4 have been bridged out so no circuit one, 5&6 on circuit 2 is probably the living room detector, 7&8 is the entry/exit circuit so if you haven’t got a contact on the front door, that more than likely will be your problem. Try bridging out 7&8 and see if the alarm sets and works properly. If it does, you need to find the wires that go to the front door and fit a door magnet switch.

Looks like the mini buzzer should be connected to 12 and 13.

 

[Nicetoseeyoutoseeyounice]

Thank you.
I now can’t wait to get home to check. I presume I need to switch off from the mains before touching anything.

 

[Mottie]

Always best to just in case you touch the 240v transformer wires.

 

[sparkymarka]

Bet that battery Is goosed