The Siren Board

I recently purchased a Federal Signal Siratrol radio (Two-tone) a few months ago and I have a radio set on the frequency and CTCSS/PL tone. When I transmit the tones on the front tag of the radio, it doesn't respond and I don't hear any relays click but the radio is picking up the tones through the antenna and I hear them from the internal speaker. There is a small burnt out lightbulb on the main board inside. The radio was originally installed in Lenawee County, MI and is set on 156.105Hz and the CTCSS tone is 186.2Hz.

Wow. That looks kinda rough. Your best bet is to bring it to a radio shop to have them look it over. Is that the one that was on eBay a while ago?

What kind of antenna is on it? If it isn't in the Frequency range of the radio it isn't going to pick it up.

WhelenBoy wrote:Wow. That looks kinda rough. Your best bet is to bring it to a radio shop to have them look it over. Is that the one that was on eBay a while ago?

Are there any radio shops that you recommend? And yes, this was on eBay a while ago.

stormsetter4 wrote:What kind of antenna is on it? If it isn't in the Frequency range of the radio it isn't going to pick it up.

The antenna (rod type antenna not sure what it is called, I plan on getting a yagi or a ground plane antenna) is in the frequency range and the radio is picking the tones I am transmitting because I can hear them from the internal speaker.

Firepro1120 wrote:The antenna (rod type antenna not sure what it is called, I plan on getting a yagi or a ground plane antenna) is in the frequency range and the radio is picking the tones I am transmitting because I can hear them from the internal speaker.

Thanks for clearing that up.

If you can hear the tones you are sending through the speaker then the receiver, CTCSS circuit, and antenna are all OK. This test doesn't verify the receiver sensitivity, but it should close relays if the decoder matches your generated tones.

The two tone decoder pictured uses L-C filters which might have been re-tuned since the tone frequencies were printed on the original label.

What are you using to generate the tones and do you have any way of verifying that the printed decode tone pairs are what the receiver is actually tuned for?

landmobile wrote:If you can hear the tones you are sending through the speaker then the receiver, CTCSS circuit, and antenna are all OK. This test doesn't verify the receiver sensitivity, but it should close relays if the decoder matches your generated tones.

The two tone decoder pictured uses L-C filters which might have been re-tuned since the tone frequencies were printed on the original label.

What are you using to generate the tones and do you have any way of verifying that the printed decode tone pairs are what the receiver is actually tuned for?

I am using Audacity to generate them and the tones I am using are on the relays on the second circuit board mounted on the door of the radio (the tones are the same ones as on the beat up front tag).

Are you using the common tone as your first (A) tone or your second (B) tone? Also, what are your tone durations and gap (if any)?

landmobile wrote:Are you using the common tone as your first (A) tone or your second (B) tone? Also, what are your tone durations and gap (if any)?

I am using the A tone for the common tone and the B tone for the function. The A tone is 3 seconds and the B tone is 2 seconds, is that right or should I use the Motorola QCII tone durations or 2+2? Also should I be using sine or square waves?

Use sine waves, and try 2 seconds for A tone and 3 secods for B. Honestly, I'm not sure exactly how the Federal decoder is designed but it might be worth a try to reverse A and B. Some coding plans refer to the B tone as the common tone.