Complicated Napco MA2600 Internals Issue

["Katie Wasserman" <katie10543@xxxxxxxxx>]

I've been reading some of the expert posts here and I know that you're
the right group for this one.....


I have a Napco MA2600 system in my house and find that it generates a
lot of RF noise from below 300KHz up to 2MHz.  Bad enough for
listening to AM radio but I recently got interested in ham radio and
that makes the problem much worse.   The RF noise is coming not just
from the AC line but from all the contact wiring throughout the house
so it's not easy to get rid of.

My solution is to shut down the alarm system completely and although
this works it's a pain to bring it up and down so I've set up a system
to do that remotely.  The "system" is a remotely control relay that
cuts off the low voltage AC into the control panel and simultaneously
the 12V battery supply.  The cutoff function works great!  But when
the system powers back up it sets off the alarm unless the AC is
applied first followed by a delay of a few seconds then the 12V
battery can be connected up.

I suppose the I could ehnace my relay circuit to add the needed delay,
but I just assume not even bother with the 12V battery and run the
system without that.  Of course you can't just pull the battery on
this system since the controller is busy with alternately charging and
checking it all the time and if it finds it's not there it won't let
you arm it.  There's no detail on the charging/checking battery system
in the manual.  If I had a schematic I'm sure that I could figure it
out but finding one seems to be an impossible task.

So I'm looking for ideas along the lines of one of these, or maybe
something entirely different.

1)  There's obviously an "AC power good, ready to accept 12V battery
voltage" signal somewhere in the panel.  If I can access that point I
can use it to control the relay for the 12V battery and not use a
fixed (and unreliable) time delay.  Where is it? There's some mention
of an optional PS3002 power supply that hooks into the control panel
through lugs E7 an E18.  Could one of these be the point that I'm
looking for, I haven't done any circuit probing yet.

2)  Faking out the battery check with a dummy battery of some sort
doesn't seem to be a workable solution, since if it really thought the
battery wasn't  there when the AC power was applied it would set of
the alarm. Turning off the battery check completely seems like it
would work but I have no idea how to do this.

3) Find some magical way to eliminate the RF noise.

4) Throw the whole thing out and buy a different system.

Thanks,

Katie