RE: Protecting Garage Door Opener

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Gary.Lau-at-hp-dot-com>

I don't believe that it is sufficient to just unplug the power cord to a
garage door opener.  The opener case is no doubt tied to the metal
strapping that mounts to the ceiling, so there is some semblance of a
ground on the case.  More importantly, the control wires that go to the
pushbutton and optical safety sensors will then act as a long antenna, with
respect to the grounded chassis.  I broke the connections to the switch and
sensors with a 3-position connector right at the back of the opener
chassis, and I religiously disconnect both that connector and the power AC
cord whenever I fire up the coil.  And for good measure, I also tuck the
little wire whip antenna back into the hole where it exits.  I don't need
to give my wife any more reasons to not like my coiling...

Regards, Gary Lau
MA, USA

 -----Original Message-----
From: 	Tesla list [mailto:tesla-at-pupman-dot-com] 
Sent:	Monday, May 27, 2002 9:51 AM
To:	tesla-at-pupman-dot-com
Subject:	Protecting Garage Door Opener

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Zimtesla-at-aol-dot-com>

Like many Tesla coilers, I run my coils in a garage. Early in the game I had
the misfortune of having the receiving board in the opener go dead after
running my coil (at that time I was using a 12kv x 60mA NST). One contributor I
think in retrospect was that I had wrapped some aluminum foil around the power
unit to act as a shield. Didn't ground it, so probably picked up RF rather than
shielding it. 

Now I only run a small coil (30mA) with the receiver card still in the opener
(opener unplugged of course). No problems. I haven't tried the bigger coil
(180mA) with the board installed since it costs $80 to replace and my wife
isn't too keen on using a push button on the wall to run the opener while I get
the card replaced. 

So I wonder, what experience is out there on protection of door openers? BTW it
is a Stanley opener, if that makes any difference. 

Thanks in advance. 
Jim