The Siren Board

Are there any known STH-C siren locations currently?

No. In fact I've never seen any literature referring to such a siren.

While I'm fairly certain none have been found still up and/or in service to date, here are some photos of one that was for sale on eBay several years ago. This is the only one I have ever seen though but I have a feeling there may be a few out there that nobody has come across yet. Best I can tell this is an all original siren that wasn't modified in any way, and man is it an old one too judging by the old Valley(?) high slip three-phase motor it has.

SuperBanshee wrote:No. In fact I've never seen any literature referring to such a siren.

murrfarms wrote:While I'm fairly certain none have been found still up and/or in service to date, here are some photos of one that was for sale on eBay several years ago. This is the only one I have ever seen though but I have a feeling there may be a few out there that nobody has come across yet. Best I can tell this is an all original siren that wasn't modified in any way, and man is it an old one too judging by the old Valley(?) high slip three-phase motor it has.

It may have never been mass produced or advertised by Federal Signal.

An interesting find! I've never seen an STH-10 with a damper before. This could not have been a long lived variation of the STH-10 as it's never mentioned in the mass of catalogs and advertisements.

Just wondering. Is it possible to fit a 3T22 intake onto the STH-10?

SoundMaster 391 wrote:Just wondering. Is it possible to fit a 3T33 intake onto the STH-10?

No. The tubing diameter for the STH-10's intake is way bigger than the 3T22's intake, plus the flange sizes (the part that bolts up to the stator) are completely different between the two sirens' intakes as well. In other words, there is no way this could work if that were a 3T22 intake even if they modified the flange to fit a STH-10; it simply would not work due to a lack of proper airflow to the siren's rotor if the smaller 3T22 tube were used.

murrfarms wrote:While I'm fairly certain none have been found still up and/or in service to date, here are some photos of one that was for sale on eBay several years ago. This is the only one I have ever seen though but I have a feeling there may be a few out there that nobody has come across yet. Best I can tell this is an all original siren that wasn't modified in any way, and man is it an old one too judging by the old Valley(?) high slip three-phase motor it has.

Could that maybe just be a 3t22 someone chopped in half?

Zarlog wrote:Could that maybe just be a 3t22 someone chopped in half?

No, highly unlikely. The intake for the STH-10 is much larger in diameter than those used on the 3T22, and this one definitely appears to have the normal size intake for a STH-10, except with the addition of a solenoid-actuated butterfly valve for coding purposes.

murrfarms wrote:

Zarlog wrote:Could that maybe just be a 3t22 someone chopped in half?

No, highly unlikely. The intake for the STH-10 is much larger in diameter than those used on the 3T22, and this one definitely appears to have the normal size intake for a STH-10, except with the addition of a solenoid-actuated butterfly valve for coding purposes.

Wow that's really really rare. This is my first time seeing one. Is this STH-C siren just a multi signal version of a STH-10 siren? Just making sure. Or is it a completely different siren model all together.