Question

[shoe]

Hi I have a Radio Shack 2018 scanner and a Vetch cordless phone .
All play well together except for frequency 155.520. If I remove the phone base unit from the area it works ok.
Is there a filter I can get for this? I get a terrible buzz

 

[cj5]

the 155 mhz dilemna

Ah, I see you're having problems with a 155MHz frequency. I don't know if I can offer any suggestions, but I sometimes experience a lot of RFI in the 155 range from various things (i.e. cordless phone, wired router, and paging systems in the area). For the paging systems I bought the filter shown at the bottom of this page (http://www.parelectronics.com/amateur.htm) and tuned it for 155 paging frequencies. The router and phone were more difficult to pin down, and even after placing a toroid around the electrtical cords (http://www.radioshack.com/product.a..._name=CTLG_011_002_009_000&product_id=273-104) I eliminated some RFI, but it's still there. The best solution is get all your antennae as far away as possible from any indoor interference.

 

[shoe]

Snap-Together Toroid Choke Core you think it is worth a try?

 

[MarkWestin]

Rs 273-105

Hello,

I haven't used the 273-104, but I am using a large quantity of 273-105s. If your phone uses an "ac adapter" type power supply, it may be radiating noise from the phone's base through the wire that goes to the "brick". While I can't say for sure that the choke will cure your noise problem, it knocked out the noises from my battery chargers. Just wrap the wire through the choke a few times as close to the jack end as possible. It also works good for serial and USB cables.

Mark

 

[cj5]

Snap-Together Toroid Choke Core you think it is worth a try?

It's not a perfect fix, but gets rid of a lot of trashy interfernce. Hell, for 8 bucks it's been the cheapest investment I've had since I started my radio hobby.

 

[shoe]

Thank you will give it a shot

 

[shoe]

well the 105 did not work any other ideas?
only disrupts 155.520

 

[W4KRR]

well the 105 did not work any other ideas?
only disrupts 155.520

Get a new cordless phone. They're pretty cheap these days.

Or get a new scanner.

Or keep the phone and scanner away from each other.

 

[Al42]

well the 105 did not work any other ideas?
only disrupts 155.520

Do you have a Linksys router?

 

[cj5]

Do you have a Linksys router?

Or a router, in general? I did the LinkSys to NetGear switch, then a NetGear to Motorola router, and got RFI from all three. I tend to think that it lies in cheap unshielded ethernet cables. I realized this the other night while playing Enemy Territory. First, I opened up the game, and logged on to a server, and as soon as I did, my scanner kept stopping on any frequency in the 155 MHz area. Disconnected from the game server, and the scanner resumed. Second, and the dead giveaway is turning on my laptop. Now when I turn it on everything is fine, but then I go ahead and plug in the ethernet cable, and the scanner does the same darned thing as with the game, until I unplug the cable from the laptop. At times, while using the internet, the scanner seems to just work fine, but when I am using a heavy amount of bandwidth (up or down), the scanner stops on anything in 155 MHz. Just some trouble shooting ideas for ya.

 

[ex8010]

I tried to fix a problem with a linksys router by using a shielded cable, and that did not work.

 

[shoe]

Or a router, in general? I did the LinkSys to NetGear switch, then a NetGear to Motorola router, and got RFI from all three. I tend to think that it lies in cheap unshielded ethernet cables. I realized this the other night while playing Enemy Territory. First, I opened up the game, and logged on to a server, and as soon as I did, my scanner kept stopping on any frequency in the 155 MHz area. Disconnected from the game server, and the scanner resumed. Second, and the dead giveaway is turning on my laptop. Now when I turn it on everything is fine, but then I go ahead and plug in the ethernet cable, and the scanner does the same darned thing as with the game, until I unplug the cable from the laptop. At times, while using the internet, the scanner seems to just work fine, but when I am using a heavy amount of bandwidth (up or down), the scanner stops on anything in 155 MHz. Just some trouble shooting ideas for ya.

No I do not

 

[cj5]

Well, then I could suggest that you check on the adapter that connects to the phone. Sometimes if the adapter is not constructed correctly (most adapters are built to cut down on RFI), and my be giving off unwanted interference.
I don't think that it's the phone itself, because it appears Vtech phones operate in the 900MHz, 2.4GHz, and 5.8GHz ranges. So it leads me to believe that it's a power source thing. If that's the case, go with a toroid choke.

 

[shoe]

point me in he direction of a torrid choke please

 

[cj5]

This is what I use:
http://www.radioshack.com/product.a..._name=CTLG_011_002_009_000&product_id=273-104

There's also this:
http://www.radioshack.com/product.a..._name=CTLG_011_002_009_000&product_id=273-105

and these:
http://www.radiodan.com/Henry/parts/RF_chokes.htm

 

[shoe]

thanks you

 

[Al42]

Or a router, in general? I did the LinkSys to NetGear switch, then a NetGear to Motorola router, and got RFI from all three. I tend to think that it lies in cheap unshielded ethernet cables.

That's one source of interference, but you'll get that all over the house, more or less, and over a wide range of frequencies. If you get a really strong signal only when you're near the router, even with no antenna on the scanner, you're hearing the router's CPU frequency, and that's usually stronger, nearby, that the noise (which is pretty random in frequency) radiated by the cables.

I realized this the other night while playing Enemy Territory. First, I opened up the game, and logged on to a server, and as soon as I did, my scanner kept stopping on any frequency in the 155 MHz area. Disconnected from the game server, and the scanner resumed. Second, and the dead giveaway is turning on my laptop. Now when I turn it on everything is fine, but then I go ahead and plug in the ethernet cable, and the scanner does the same darned thing as with the game, until I unplug the cable from the laptop. At times, while using the internet, the scanner seems to just work fine, but when I am using a heavy amount of bandwidth (up or down), the scanner stops on anything in 155 MHz. Just some trouble shooting ideas for ya.

You can sometimes counter hash (which is what you're getting - broadband noise) by tightening up the squelch. Of course this eliminates receiving the weaker stations, but you'll still scan, and hear the strongest ones.

 

[shoe]

All I use is a speed stream 3060 internal PCI DSL modem