Scantronic R500 Alarm Rf Supervision Failure

[charlie6]

"...It is possible, that a 'jamming frequency' from the property next door may be responsible if that signal were strong enough.."

Sorry, I should have explained that the jamming frequency could be coming from virtually anything, not their alarm. It could emanate from the weird and wonderful sound systems they are using these days, or a CB radio, or a Freezer kept in their garden shed and so on. The housing development has a lot of traffic so good on you for spotting that all too often overlooked aspect, and you appear to be on the receiving end of all of it. You could be putting yourself 'between a rock and a hard place' on this one, but it might be worth getting your installer to reduce the time duration of the external warning device for a week or so if he can't find the problem immediately. The plus side is that the neighbours don't get annoyed, the minus side is you have less sounder time in the event of a genuine burglary attempt. Keep looking (and listening), keep logging the times.

[datadiffusion]

 

-I believe the alarm system is app roc 7-8 years old, bought by previous owners, installed professionally

 

It's unlikely, unless the installer had VERY old stock. IIRC the 500r was obsoleted very early on in Scantronic wireless history,

due to it using 418 and then 433Mhz wireless devices. Most units will be around the 15-20 year old range, sadly now that

Cooper are Eaton, the useful web pages showing obsolescence dates for various items is gone

Edited September 1, 2015 by datadiffusion

[Skj10001]

"...It is possible, that a 'jamming frequency' from the property next door may be responsible if that signal were strong enough.."Sorry, I should have explained that the jamming frequency could be coming from virtually anything, not their alarm. It could emanate from the weird and wonderful sound systems they are using these days, or a CB radio, or a Freezer kept in their garden shed and so on. The housing development has a lot of traffic so good on you for spotting that all too often overlooked aspect, and you appear to be on the receiving end of all of it. You could be putting yourself 'between a rock and a hard place' on this one, but it might be worth getting your installer to reduce the time duration of the external warning device for a week or so if he can't find the problem immediately. The plus side is that the neighbours don't get annoyed, the minus side is you have less sounder time in the event of a genuine burglary attempt. Keep looking (and listening), keep logging the times.

Re the passing traffic, when I put the panel into "walk test mode" it displays when there is rf trouble, flashing Amber, generally when cars are passing leaving the development. Sometimes it shows steady Amber for few longer seconds.

Why would it trigger an alarm at particular times and not others? Is there a particular car or device active at the precise time the sensor is trying to send a signal back to the panel? How often are signal suppose to be sent/recieved? Does is only occur when house alarmed? Can it occur when alarm is on standby?

Thanks in advance

[datadiffusion]

I would double check the manual as with panels like these, in Walk Test or Engineer mode, LEDs may have different meanings.

 

i.e in Engineer Mode, Walk Test could mean an option is turned on or off and have nothing to do with the label applied to it, which only

applies in 'day' mode. In fact, I believe that this LED means '9' in engineer mode.

 

However, the user manual does state that;

 

 

Jamming LED flashing

• Control unit detecting interference on same frequency as detectors.

• Wait till Jamming LED goes out. If problem persists, call Scantronic Technical Support.

 

It does not give any help for a solid 'jamming' LED.

Edited September 1, 2015 by datadiffusion

[james.wilson]

Has someone recently enabled 4g in your area plus are you running a 433MHz or 868. Not sure if the 500r was available with different freq?

[Skj10001]

Has someone recently enabled 4g in your area plus are you running a 433MHz or 868. Not sure if the 500r was available with different freq?

By someone do you mean a network provider?

How can I tell what frequency I'm running on?

Thanks

[charlie6]

Hello SKJ, as I mentioned earlier this is a jamming problem where the panel detects an external frequency which is very close or the same as the frequencies used by that panel. The The radio operating frequency is 418MHz with a bandwidth of 200kHz and at one time conformed to BS6799 class III, it also complied at that time with the nacoss codes of practise. Now forget the rest of the gobbledegook and just look at the 200kHz bandwidth. In simple terms this means 200,000 cycles per second and is not regarded as a narrow bandwidth by today's standards, therefore there is a far greater chance that an external frequency within this window should jam your panel. Now, you may say, since this is the case then I should buy a new panel. In doing so, you would also need to buy a new batch of detectors which shoots your costs up considerably, and that's just the equipment. Although virtually anyone can install 'wireless' should you opt for a 'professional' (in inverted commas) to do the job for you then add a considerable sum to the cost of your new equipment before you start.

 

So, that's the bad news. The good news is that you have almost found the problem, in that you are beginning to look for certain cars and at certain times. One of the golden rules in wireless is to avoid metal, but I have often used simple kitchen foil, not to keep the signals in, but to keep jamming signals out, I'll explain that a little later. We are at that point then where the panel detects a jamming signal when a car (and I'm reckoning on a particular car) is leaving the development. Do you ever use too much rev's when starting your car and driving away..I know I do... and excessive revving of a car engine is 'leaning on' the 200kHz bandwidth. Now, I'm not suggesting that you have actually found the problem but I am sure that you are 'on the case'. You mentioned:-

 

"Why would it trigger an alarm at particular times and not others? Is there a particular car or device active at the precise time the sensor is trying to send a signal back to the panel?.." Every probability that this is indeed the case. Have you considered asking your installer to reduce the external warning device time for a short period ? Keep digging, you're getting there.

Edited September 1, 2015 by charlie6

[datadiffusion]

Has someone recently enabled 4g in your area plus are you running a 433MHz or 868. Not sure if the 500r was available with different freq?

500r was 418, 500r+ was 433 afaik

[al-yeti]

Basically the old frequencies are more subsebtle to types of interference, hence why better to update , not just alarms mind you , when they shifted the frequencies for what they are used for quite a few things were updated by manufacturers and it just depends on how much of a priority it became for an individual or organisation to follow suit and update

[charlie6]

Hello SKJ, Although I mentioned that 418 is fairly wide, I'm sorry to inform you that even the newer narrow band, were you to buy brand new, at a phenomenol cost if it was trade installed, would not cure your present problem.

Both the 500r and 500r+ are at 418, the only discernible difference of any weight is the facility to add a digital communicator to the r+ so this needn't concern you.

Edited September 2, 2015 by charlie6