Batboard

I have a question about these; from looking at the Systems*90 control head this came with (system was originally Mitrek based), it doesn't appear that Airhorn was an option at the time. Also, I notice that the "Off" button is push-on-push-off, not a solid, switch button like the siren mode buttons.

Does manual do airhorn, or was this simply not a function for this siren unit? Can I still get a manual or hook-up guide (cable pinout)?

No airhorn, the manual mode lets you use horn ring or a footswitch, when you close the switch the siren starts and the pitch rises, then when you release the switch the pitch falls again.. it doesn't even cycle by itself, when they say manual, they mean it!

The TLN1691 is not actually the siren, it's the amplifier.. the siren functions are all generated in the control head. The output and driver transistors are germanium, pretty hard to find now.. last time I tried to order some they were something like $40 a piece. I never tried changing them to silicon types, not sure what would be involved in that, but I guess it's possible.

Jack,

Thanks for the info. I'd always wondered.