Tue Oct 25, 2016 5:52 am
As others have already stated, it is not illegal to posess, own or operate the Siratrol receiver/tone decoder. The legality issues arise with the activation capabilities. To transmit on frequencies used to activate any Siratrol requires a Federal Comunication Commision (FCC) license. Licenses are required to transmit on all commercial two-way radio frequencies. This includes the high band VHF, low band VHF and UHF frequencies used by all Siratrol ARCH, ARCL and ARCU receiver/tone decoders. The purpose of the license is to assign frequencies so that no one is interfering with another's communications. It is just a way to keep communications orderly. Even if you were to successfully change the frequency of your Siratrol you would still legally require a license to transmit on that new frequency.
You can legally purchase the equipment to transmit. You can even legally have that equipment programmed to transmit on the frequency to activate your Siratrol with no questions asked.
Will the FCC do an all out man hunt for you if you do transmit on a frequency that you do not have a license for? Probably not as long as you do it very infrequently, but the risk is still there. There is also the risk that you could transmit over another critical transmission.
In the real world installations the siren system was activated at a base station. The base station had a desk top two-way base radio connected to a tone encoder. The tone encoder had several buttons for different sectors of the siren system so you could activate the entire siren system or a smaller portion of the system. When an activation button was pushed the tone encoder closed an internal relay for radio transmission. The tone encoder would then transmit a sequence of two different tones about one second apart. The Siratrol at the siren would receive the transmission in the tone decoder. The tone reads in the Siratrol tone decoder had to discriminate if the tones that were received were the correct tones, in the correct order and in the correct time spacing. If the Siratrol received everything correctly it would close the appropriate relay for the function assigned to those two tones whether it was for alert, attack, fire or cancel.
I do have a Siratrol manual if you need to know something.
Owner of a Federal Electric Model 2, Federal Sign and Signal SD-10, Federal Sign and Signal 1000(T) and a H.O.R. Si-Rex 7:10 Omnidirectional