rickb@tekig4.UUCP (Rick Bensene) (08/26/86)
Greetings,
I've read with interest recent postings in net.micro (is this where
these discussions should be held?) regarding the BSR home control
system. I have one of the 'new' Radio Shack CoCo Home Controller
modules, two BSR command consoles, and a bunch of light switch modules,
appliance modules, etc. I have the CoCo Controller set up to handle
routine scheduled events like turning on the flood lights at dusk,
etc. The command consoles are used to control lighting in various
rooms of the house. The whole system worked wonderfully until one
day...when I got my new computer (A Tektronix 6130 Unix Workstation)
and set it up. Once I got the new system connected up and running,
the BSR modules started behaving VERY strangely...they would randomly
turn themselves on and off. It was rather surprizing to have the bedroomm
light come on at 3:00 AM. The only thing that I can figure is that
the 6130 is somehow broadcasting 'noise' on the power line which fools
the remote switches into thinking they are receiving valid commands
to do things. The 6130 system is connected to the power grid through a
power strip with built-in noise/surge suppression, and the power
strip is plugged into another box which is also a surge protector and
line conditioner. I know these surge/noise suppressors supress noise
going INTO the equipment to which they are connected, but do they
help keep noise from the connected equipment from leaking back into
the power line? No, there are no neighbors near by who have
'broken in' to my system and are playing games...there are two
houses served by the transformer, ours and a trusted neighbor, so I
have to believe that the problem is due to some kind of electrical
noise on the lines. The random action of the modules is fairly
rare, however, the interference also seems to reduce the ability
of the whole system to operate reliably...only modules which are
very close to a command console seem to work reliably. I have
heard rumor that it is possible to install capacitors or somesuch
in the house wiring that helps to filter out interference which
prevents the remote switches from operating properly, but do not
know the particulars. Does anyone out there have any clues as to
how I might be able to solve this problem? I would really like to
get the system working again...without having to shut my Unix system
down. The correlation of the problem with the installation of the
Unix system may be coincidental...I've never had my system down
long enough to tell if the problem abates while the computer is
shut down.
Eagerly awaiting any suggestions, comments, or whatever.
Rick Bensene
..tektronix!tekig4!rickb (work)
..tektronix!reed!{omen,percival}!bucket!rickb (home)rickb@tekig4.UUCP (Rick Bensene) (08/27/86)
In article <900@tekig4.UUCP>, rickb@tekig4.UUCP (Rick Bensene) writes: > Greetings, > > I've read with interest recent postings in net.micro (is this where > these discussions should be held?) regarding the BSR home control > system. I have one of the 'new' Radio Shack CoCo Home Controller > modules, two BSR command consoles, and a bunch of light switch modules, > appliance modules, etc. I have the CoCo Controller set up to handle > routine scheduled events like turning on the flood lights at dusk, > etc. The command consoles are used to control lighting in various > rooms of the house. The whole system worked wonderfully until one !> day...when I got my new computer (A Tektronix 6130 Unix Workstation) !> and set it up. Once I got the new system connected up and running, !> the BSR modules started behaving VERY strangely...they would randomly !> turn themselves on and off. It was rather surprizing to have the bedroomm !> light come on at 3:00 AM. The only thing that I can figure is that !!> the 6130 is somehow broadcasting 'noise' on the power line which fools !!> the remote switches into thinking they are receiving valid commands !!> to do things. I should clarify the statements marked above with !'s a little in order that I don't shed a bad light on Tektronix for manufacturing equipment that emits all kinds of 'noise'. The 6130 that I have is a non-production unit...built up from parts. It is not enclosed in a cabinet and probably does emit all kinds of RFI and EMI. Tektronix production 6130's are completely certified by the FCC and VDE as meeting all standards for radiated interference. If my computer is indeed the cause of the interference (through no fault of Tektronix's) is there any way of filtering out this interference without resorting to encasing the machine in a wire mesh cage? Sorry about any misconceptions this may have caused. Rick Bensene ..tektronix!tekig4!rickb (work) ..tektronix!reed!{omen,percival}!bucket!rickb (home) Phone: Weekdays (503) 627-3559 (work) US Mail: Tektronix, Inc. - P.O. Box 500, Mail Stop 39-170 - Beaverton, Oregon 97077
cmcmanis@sun.uucp (Chuck McManis) (08/28/86)
> Greetings, > > ... lots of stuff about BSR thingies ... > > ... The 6130 system is connected to the power grid through a > power strip with built-in noise/surge suppression, and the power > strip is plugged into another box which is also a surge protector and > line conditioner. ... ^^^ The critical fact. Rick please note that a lot of surge suppressors (and some home electronics equipment) connect two capacitors between the power line to ground like so : || || hot +-----||------+-------||------+ return || | || + ground These capacitors suppress noise by shunting it to ground (the 3dB rolloff point is at about 50KHz) Last I heard the BSR's used a 200KHz carrier, if that is the case these cap's would look like very nearly dead shorts to ground. Assuming you have a commonly wired house that makes it tough on the controller to send anything. You can fix it two ways, remove the power strips, or put the computer on an isolation transformer and then power strips. --Chuck McManis {anywhere}!sun!cmcmanis These are my opinions and no one elses, but you knew that didn't you.
Dale_E._Yocum.osbunorth@Xerox.COM (08/29/86)
Rick, I also have been bitten by the X-10 bug and have spent the last few months getting mine to work reliably. Here's some ideas: 1) Capacitors can indeed be installed which will make the system more likely to hear it's OWN signals. The biggest loss seems to come the transformer up on the pole. Since most houses divide the 240 VAC from the pole into two different 120VAC circuits, a capacitor can help couple these two circuits together at the frequencies used by the X-10 system (around 200KHz) while keeping them separate at the lower 60Hz. I installed a .1mf, 600V capacitor across the two circuits in the circuit breaker box. It helped a lot. But I wouldn't recommend you do it yourself if you're not comfortable with electrical work. 2) The capacitors will NOT help filter out the noise from your Unix system, though. (If anything, it might make it's signals travel better!) For that, you need to filter out the noise before it gets into your homes power grid. A surge protector will NOT do this. What you need is a power line filter (also called a noise suppressor), not just a surge protector. The gound going to this outlet must also be good. I know SPC Technology makes such things, but I'm sure there are others as well. 3) It's hard for me to imagine, though, that your system could be spraying out noise in the same digital packet format as the X-10. Anything is possible, but don't be surprised if this doesn't solve the problem. I would tend to look at the Radio Shack controller if the filter doesn't seem to help. It's microprocessor may be going temporarily insane. Free advice is worth everything you pay for it. Dale
brucev@tekigm.UUCP (Bruce D. Virell) (08/30/86)
In article <6653@sun.uucp>, cmcmanis@sun.uucp (Chuck McManis) writes: > . . . . . > please note that a lot of surge suppressors (and some home > electronics equipment) connect two capacitors between the power > line to ground like so : > || || > hot +-----||------+-------||------+ return > || | || > + > ground > These capacitors suppress noise by shunting it to ground (the 3dB > rolloff point is at about 50KHz) Last I heard the BSR's used a > 200KHz carrier, if that is the case these cap's would look like ^^^^^^ close, it's spec'd at 121KHz in the design info BSR sent out. > very nearly dead shorts to ground.