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Alert Monitor Auto Reset

Posted: Sun Nov 23, 2008 2:04 pm
by Two Tone
I have an Alert Monitor model# L01CND7100A, and I am looking for a way to automatically reset itself when the tones are done going out. Is there a way to modify it to do so?

Thanks! :P

Re: Alert Monitor Auto Reset

Posted: Thu Nov 27, 2008 9:04 am
by Vern
I've seen this done, with a homemade circuit using a 555 timer. I would imagine that a commercially available timer board would be easy to interface to that radio. The Altronix 6062 is a neat little timer with lots of features. These are usually found at alarm suppliers, not very expensive. Making it fit inside the radio might be a challenge.


Vern

Re: Alert Monitor Auto Reset

Posted: Sun Dec 07, 2008 9:00 pm
by Two Tone
Thank you, Vern! I think i may take a look further into your suggestion. Does anyone else have any suggestions?

Re: Alert Monitor Auto Reset

Posted: Wed Dec 10, 2008 3:37 pm
by hvfcadmin
Yes the NE555 setup as a one shot does the trick, Ive done this to many alert monitors, if you still need the info i can look for the schematic of the board i designed for the alert monitors. Moto used to use a board inside of them to do this feature. There are 2 types, one just resets the monitor after 5 sec. I found this to be ok but the relay output stays on for 5 sec, way to long for me (dispatch would start talking before horns shut off). so i made the NE555 circuit trigger off of the relay +12v pulse, and trigger the relay off of the 555. This way i could control how long the relay was on and the unit would still reset after 5 sec.

Re: Alert Monitor Auto Reset

Posted: Thu Dec 11, 2008 10:09 am
by Two Tone
Yes! Any schematics anyone may have would be greatly appreciated! PM sent to hvfcadmin.

Thanks!

Re: Alert Monitor Auto Reset

Posted: Sat Jan 03, 2009 4:41 pm
by jban
I would like a copy of the diagram as well if you don't mind.