Hi Graham14,
The symptoms that you describe is definitely due to a degraded power supply as Lee has suggested.
Replacements can also be obtained from Amazon.
Here is a description of the fault and how this affects the operation of the Sure Signal (a bit technical in places).
The psu for Sure Signal is a fairly bog standard electrolytic capacitor filter unit.
Bear in mind that these PSU's are likely to be running 24/7 and do create an amount of heat ....... This heat over a period of time dries out the electrolyte hence reducing the capacitance to a level where the PSU can only provide enough power to enable the activation process (lights 1+2). This is enough for the VF server to activate the 3G signal (light 4). At this point the current requirement goes from a modest few hundred milliamps to approx. 1.2 Amps, this is when the PSU just gives up and the supply drops from 12 volts to around 6-8 volts with a heavy A.C. content which will briefly shut down the Sure Signal. As the PSU is no longer providing power, the Voltage will rise again to an acceptable level to allow the activation to start again until it reaches the 3G activation point and so on. We refer to this as cycling or looping.
I think Sagem didn't give enough thought to the design of the power unit and made it cheaply as possible. However, considering they are usually running 24/7 throughout the year, the life of these PSU's is generally 4-6 years.
The red herring with this fault is that the power light (Light 1) is always illuminated and never goes out!
Regards,
Mike.
The sure signal unit has suddenly started working again after not working for 24 hrs! I wonder if it could still do with a new power supply as its been on for four years? Maybe it's a sign it's on it's last legs and might be prone to overheating or cutting out?
