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micky micky is offline
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Default Will no output devie hurt output transistors?

Years ago, I was told not to play my stereo with no speakers, for fear
of somethun' or other. Of course that was 1968, a good year for audio.

Is this still an issue with current electronics, like audio amplifiers
and burglar alarm amplifiers?

Now I have a home burglar alarm that might be in the alarm status. I
can't tell because I disconnected part of it, until I can find out how
to disarm it.

I have two horns and a siren driving amplifier board, so that they're
louder than the mere alarm control panel can provide. I have a glass
fuse in the line to each speaker.

So if I take the fuse out but the siren driver is still functioning, do
I risk burning it out? Even if it's like this for say, 20 hours?

Or can it go like this with no harm to itself?

What if I disconnect the siren driver from the control panel? They're
separate boards. Do I risk burning out the output of the alarm control
panel, if say it is run. again, 20 hours?

Or can it go like this with no harm to itself?


Those are the questions. The rest here is just a narrative, soon to be a
major motion picture.

20 hours is how long I need to look into it, sleep, and then contact my
friend who runs an alarm business. But I'd really like to do as much as
possible on my own. He's constantly doing favors for me and a couple
days ago he wanted to send over his technician to finish the
installation for me. I can offer to pay; i can insist on paying, but I
know he won't let me, and, trust my judgment, he probably wants the
kavod of helping me more than he wants the money. Plus my own ego is
involved in wanting to do it myself...., so I really shouldn't be asking
you any questions either. But it's different. None of you are coming to
my house to do it.

The reason it's running is that I tried the original default master
code, several times, and it didn't work. It wouldn't arm the system,
but I wanted to hear if the siren worked (this system has never been
tested before) and soon I got the bright idea to arm it another way.
there is an Away button which when pushed for 2 seconds arms it without
the code. Well the siren works, as well as it did when I had my
previous system installed (designed and installed by me, but it burned
out after 15 years. Lightning?) but I didn't look far enough ahead to
realize still didn't have a code that worked and I have no way to turn
it off.

Well, I unplugged it, and the battery hasn't been charged in 9 years, so
that turned it off, but I need to work on it and the moment I plugged it
in again, it armed itself.