Re: Topband: 200 Amp low pass filter for power mains?

Check your door bell transformer. And the button. If you shut off the main breaker and the noise is gone it is likely something energized by the main power is generating noise. If you switch off ALL the load breakers at the same time, the noise should be the same as when you shut off the main.

Re: Topband: Nasty QRM From ??

Toggling switch also keeps people from going down the street seeing which doors they can open because its using a canned security code. We had one yesterday on a bicycle ride down the street. -nope would not open ours code changed PLUS its turned off when we are here. Hank K7HP | Toggling

Re: Topband: Nasty QRM From ??

Jim, Lets take this off list and I'll tell / show you what I have already tried. Thanks, Steve NG0G On 1/24/20 4:50 PM, Jim Brown wrote: On 1/24/2020 2:31 PM, Stephen Hawkins wrote: Toggling a switch rather then disassembling two under warranty garage door openers and splicing in a non

Re: Topband: Nasty QRM From ??

On 1/24/2020 2:31 PM, Stephen Hawkins wrote: Toggling a switch rather then disassembling two under warranty garage door openers and splicing in a non switching supply is a much easier solution for me. Steve, Sorry, I missed that the PSUs were internal to the units. I do agree. However --

Re: Topband: Nasty QRM From ??

Jim, Toggling a switch rather then disassembling two under warranty garage door openers and splicing in a non switching supply is a much easier solution for me. Steve On 1/24/20 2:15 PM, Jim Brown wrote: On 1/24/2020 9:39 AM, Stephen Hawkins wrote: I have two new Chamberlain Garage Door

Re: Topband: 200 Amp low pass filter for power mains?

Your local power company is responsible to provide RFI free power. If you have determined that your noise is not coming from sources in your home then a friendly phone call to the power company may solve the problem. Most power companys have a trained RFI tech that can help. Good luck. Larry  

Re: Topband: Nasty QRM From ??

On 1/24/2020 9:39 AM, Stephen Hawkins wrote: I have two new Chamberlain Garage Door openers that have cheap Chinese switching supplies in them that use the wires to the switch at the people door and the wires to the sensors at the bottom of the roll up doors as antenna. Despite toroids and

Re: Topband: Nasty QRM From ??

On 1/23/2020 10:59 PM, Dick Bingham wrote: Have any of you encountered similar ~98.xxxKHz spurious signals ? NK7Z's website has waterfall and spectrum plots of a wide variety of KNOWN noise sources. It would be a good starting point. His website and mine both include lots of detailed advice

Re: Topband: 200 Amp low pass filter for power mains?

“ I suspect you still have something energized in your house” Been there, done thatin my case battery backup in the modem for the voip telephone, terrible square wave Sent from my iPad > On Jan 24, 2020, at 2:38 PM, Richard (Rick) Karlquist > wrote: > > On 1/24/2020 10:21 AM, Ron

Re: Topband: 200 Amp low pass filter for power mains?

On 1/24/2020 10:21 AM, Ron AE5E via Topband wrote: I think a good share of noise on 160 for me is coming in on the power line.  The ground mounted transformer is about 1000' feet away and serves other homes as well as mine.  The lines are all buried.  Where it entered the house I would like

Topband: 200 Amp low pass filter for power mains?

I think a good share of noise on 160 for me is coming in on the power line.  The ground mounted transformer is about 1000' feet away and serves other homes as well as mine.  The lines are all buried.  Where it entered the house I would like to try to suppress noise. I can turn off all lights,

Re: Topband: Nasty QRM From ??

The fact that it is frequency stable, not drifty, rings me a bell. SMPS noise is drifty. Perhaps after shutting down the house-mains and with a portable receiver with ferrite bar antenna (MW band tuned, so you can estimate where the noise come from, although you'll get two

Re: Topband: Nasty QRM From ??

You need to kill the main breaker, Dick, and walk over to the power panel with a 6 transistor radio and if you have HASH, then you need to call the power company and tell them to get their piece of junk off the house. I had the same issue. I think that most of us here have. It's a pretty

Re: Topband: Nasty QRM From ??

Dick, if you have a portable AM radio, try sniffing around your power meter and any cable leads (tv, internet) that are coming into the house ... while you have main breaker pulled. If nil then start a search in the local neighbourhood making note of where it gets louder. You should

Re: Topband: Nasty QRM From ??

Dick, On 1/24/20 11:20 AM, k8...@alphacomm.net wrote: These signals are frequency stable and not drifty. Shutting down the house-mains with the receiver battery powered does not kill the QRM. How about your garage?  I have two new Chamberlain Garage Door openers that have cheap Chinese

Re: Topband: Nasty QRM From ??

Just a thought, does your house have the new "intelligent" power metering on the powerline? This would still be on, even if your breakers were off. Or, maybe the same type of monitoring on natural gas or municipal water supplies. Sure sounds like a switching power supply Brian  K8BHZ On

Re: Topband: Nasty QRM From ??

On 1/23/2020 11:59 PM, Dick Bingham wrote: ... These signals are frequency stable and not drifty. Shutting down the house-mains with the receiver battery powered does not kill the QRM. SO, it looks like something somewhere is generating this junk that runs from the BC-band to >20MHz. Shutting

Re: Topband: Beverage performance VS term resistor

Hi Dave, I use 4Nec2. It is freeware and calculates RDF directly: https://www.qsl.net/4nec2/ steve ve6wz > On Jan 24, 2020, at 7:21 AM, Artek Manuals wrote: > > Steve > > I am curious, what antenna modeling program are you using that gives direct > readout in

Re: Topband: Beverage performance VS term resistor

In EZNEC the RDF number is the difference between the average gain and the gain at the elevation angle you select. W8JI uses 20 degrees as the reference and some other systems use a slightly different angle. You have to run a 3 dimensional plot and the average gain number will appear at the

Topband: RDF vs F/B

Steve et all I think both characteristics of receiving antennas are important depending on your location and the types of noise you are looking to "minimize" For those of you (and I at one time)  who have the good fortune to be located in relative quiet rural / remote environments like the

Re: Topband: Beverage performance VS term resistor

Thanks...I did not know that. I am running Eznec+ 6.0 here which is based on a version of NEC2 but the GUI doesn't address RDF ( will have to give Lewellyn a poke about that 8^) Dave NR1DX On 1/24/2020 9:25 AM, Don Kirk wrote: Hi Dave, I use 4nec2 which is free, and it provides direct

Re: Topband: Nasty QRM From ??

I see you mentioned you checked everything with the power off. I would look at utility poles maybe cable or fiber power supplies?? Also I have have had my sdr settings not correct and have seen what I thought was QRM... Maybe try another receiver? Good luck Fred KB4QZH  Original

Re: Topband: Beverage performance VS term resistor

Steve I am curious, what antenna modeling program are you using that gives direct readout in RDF? Or are you  "estimating"  it from the antenna graphical pattern? Dave NR1DX The recent experiments with my Beverages in the cold weather has raised some comments about the termination resistor

Re: Topband: Nasty QRM From ??

Dick There are many sources that can generate this kind of "noise" . More common of recent are variable speed blower motors in modern furnaces and central A/C units. Next are cheap switch mode power supplies from a plethora of items, manufactured in PRC. And finally outdoor lights that come