False alarm issue

[Ashton]

Just wondering if any one has ever had an issue with the old style Honeywell dt755 , all the detectors I have in use are these but I have one that keeps false alarming only when large vehicles seem to go past (cctv checked at activation times ) all voltages and resistances readings are fine device replaced set on its lowest sensitivity setting still happens at a bit of a loss to be honest 

Edited October 21, 2017 by Ashton

[Ashton]

Weird thing is aswell on 2 of the activations the same van went past was wondering could it be some sort of rf interference ?

Edited October 21, 2017 by Ashton

[al-yeti]

Vibration loose connection or damaged cable?

[MrHappy]

these van casting shadows across the rm ?

[datadiffusion]

5 hours ago, Ashton said:

Weird thing is aswell on 2 of the activations the same van went past was wondering could it be some sort of rf interference ?

 

Could have been an MI5 / TV detector van shifting a recently crashed UFO across the county whilst trying to stop Trump publishing details of Kennedy...?

[Ashton]

 I'm siding with the MI5 theory tried changing cores on cable panel has an ac suppressor fitted tried changing Cct from panel to local expander its calmed down a lot since changing sensitivity level (dropped microwave to low level and selected dip switch 1 to Lower setting) but still happens now and again the van theory came from thinking it must be environmental but trying to narrow down what happened at point of activation and only thing in common is large removal vans/council trucks go past all connections re made when I changed the cores 

distance wise from the vehicle aspect Is a good 10-15 meters out of the window to a facing mini round about 

[Ashton]

And them tv detection vans how ever did they know I was picking up a tv signal 

[Ashton]

Was just after something to go at I know a number of years ago the Honeywell elephant catchers had An issue with beacons/strobes on forklifts etc sending them into a tamper condition just wondered if there was something with the Honeywell 7550 I'm unaware about 

[sjsturner]

Have you tried swapping one with another to see if the fault moves to the other room?

only the guts not the whole thing.

 

i had these in my old house for years and never had any problems.

[Ashton]

Hi I have tried 3 different boards but not actually swapped them around with each other and I know I have these in all rooms and they are usually bullet proof so that's why I'm struggling with this issue