Computers & Electronics

Outdoor Timer Wireless Remote Interference - What Causes It?

  • Last Updated:
  • Apr 20th, 2019 7:49 pm
[OP]
Deal Guru
Mar 22, 2004
13254 posts
3676 upvotes
RFD

Outdoor Timer Wireless Remote Interference - What Causes It?

Just curious to know in layman term the reasoning behind this with people who have knowledge of RF interference. I didn't know such a thing was possible in this specific manner.

I bought a Fosmon Outdoor Timer on Amazon that comes with a RF remote. I haven't noticed this until now, but every time I hold any button on this remote, my 2005 Ford's vehicle headlights will turn on and pulsate at dim but noticeable brightness. I noticed this through an outdoor camera live feed and I just went outside and did the same thing, press and held any button, and saw the headlights up close turn on at dim but still noticeable brightness and start pulsating in brightness.

What module in the Ford is causing the headlights to come on when using this RF remote? The remote is interfering with something. I just find this a little fascinating that vehicle headlights can turn on by a remote. It's not as if the car has wifi.

Image
12 replies
Deal Fanatic
User avatar
Oct 8, 2006
5485 posts
518 upvotes
Toronto
does your car have a remove starter or remote unlocking?
[OP]
Deal Guru
Mar 22, 2004
13254 posts
3676 upvotes
RFD
killoverme wrote: does your car have a remove starter or remote unlocking?
No remote starter.

It has an OEM key FOB that has door unlock/lock, trunk release, emergency horn.
Deal Fanatic
User avatar
Oct 8, 2006
5485 posts
518 upvotes
Toronto
radeonboy wrote: No remote starter.

It has an OEM key FOB that has door unlock/lock, trunk release, emergency horn.
Might be a unlocking/locking thing then. I know my car headlights light up when I lock/unlock. So they are just the same 'RF' signal as your car. Hopefully it doesn't also unlock your car...
[OP]
Deal Guru
Mar 22, 2004
13254 posts
3676 upvotes
RFD
killoverme wrote: Might be a unlocking/locking thing then. I know my car headlights light up when I lock/unlock. So they are just the same 'RF' signal as your car. Hopefully it doesn't also unlock your car...
Hmmm...I'll have to go and check tomorrow morning if it unlocks the car. Good tip thanks!
Sr. Member
Sep 13, 2011
895 posts
534 upvotes
Québec
I could help you, but you need to take a picture of the FCC or IC certification number on your device.
Deal Addict
User avatar
Oct 14, 2010
1333 posts
774 upvotes
Barrie ON
radeonboy wrote: It's not as if the car has wifi.
These remotes don't use Wi-Fi which is in the 2.4 ghZ and 5 gHz range of the electromagnetic spectrum. These remotes are most likely using frequencies in the 300 mHz range.

You should lookup the frequency of both your key fob frequency, and outlet remote control, and see if they happen to be on the same frequency.

To do this, find the FCC code on each device. It may be printed on a sticker, or molded into the plastic case, as it is in this image.

After obtaining the two codes, go to this LINK and enter the codes. You will then be given a lot of data on the device including the operating frequency. The images are an example of searching for my Toyota key fob.

Image
Image

Image
[OP]
Deal Guru
Mar 22, 2004
13254 posts
3676 upvotes
RFD
Thank you both for your help. Seems to be the likely reason as it makes sense. Be on the same frequency but also have the same transmit code?

I tried inputting in the FCC.gov link that @Rick007 posted but kept coming up with not being able to find an application for both remotes.

Here is the information I used...

Ford Remote FCC ID: CWTWB1U331
Fosmon Remote FCC ID: PAGTR020S
elgros4 wrote: I could help you, but you need to take a picture of the FCC or IC certification number on your device.
Rick007 wrote: These remotes don't use Wi-Fi which is in the 2.4 ghZ and 5 gHz range of the electromagnetic spectrum. These remotes are most likely using frequencies in the 300 mHz range.

You should lookup the frequency of both your key fob frequency, and outlet remote control, and see if they happen to be on the same frequency.

To do this, find the FCC code on each device. It may be printed on a sticker, or molded into the plastic case, as it is in this image.

After obtaining the two codes, go to this LINK and enter the codes. You will then be given a lot of data on the device including the operating frequency. The images are an example of searching for my Toyota key fob.

Image
Image

Image
Sr. Member
Sep 13, 2011
895 posts
534 upvotes
Québec
I can tell you that both devices used frequencies in the 315 MHz range. Ford (and other brands) are know to be vulnerable to remote wireless hacking and it's seem your fossmon radio is illegal in Canada.

For more infos on wireless hacking vulnerabiliy:
https://www.tomsguide.com/us/wireless-c ... 23169.html
[OP]
Deal Guru
Mar 22, 2004
13254 posts
3676 upvotes
RFD
elgros4 wrote: I can tell you that both devices used frequencies in the 315 MHz range. Ford (and other brands) are know to be vulnerable to remote wireless hacking and it's seem your fossmon radio is illegal in Canada.

For more infos on wireless hacking vulnerabiliy:
https://www.tomsguide.com/us/wireless-c ... 23169.html
Very interesting! Should be alright as this Ford is old and beat up ugly that it shouldn't be a target for being stolen. But I love reading and knowing of such things. Thanks @elgros4
Deal Addict
User avatar
Oct 14, 2010
1333 posts
774 upvotes
Barrie ON
radeonboy wrote: I tried inputting in the FCC.gov link that @Rick007 posted but kept coming up with not being able to find an application for both remotes.

Ford Remote FCC ID: CWTWB1U331
Fosmon Remote FCC ID: PAGTR020S
If you are indeed interested in reading the details of each device, here are the links

Ford Remote
Fosmon Remote

You might be interested in reading the Test Reports, and looking at the radiated spurious emissions among other things.

Your problem nay be caused by the Fosmon remote transmitting a large number of spurious tones, or the RF filters in your car's receiver are not cutting off these tones.

Try operating the remote near other vehicles. Almost all car remotes use similar frequencies.
Sr. Member
Sep 13, 2011
895 posts
534 upvotes
Québec
Rick007 wrote: If you are indeed interested in reading the details of each device, here are the links

Ford Remote
Fosmon Remote

That's not how rf filters operates, they are use to filters out offset carriers frequencies not tones.
Also, spurious tones is not a thing. Spurious frequencies, yes but not spurious tones.
You might be interested in reading the Test Reports, and looking at the radiated spurious emissions among other things.

Your problem nay be caused by the Fosmon remote transmitting a large number of spurious tones, or the RF filters in your car's receiver are not cutting off these tones.

Try operating the remote near other vehicles. Almost all car remotes use similar frequencies.
Deal Addict
User avatar
Oct 14, 2010
1333 posts
774 upvotes
Barrie ON
elgros4 wrote: That's not how rf filters operates, they are use to filters out offset carriers frequencies not tones.
Also, spurious tones is not a thing. Spurious frequencies, yes but not spurious tones.
Yes you are correct that an RF filter in a receiver is used to attenuate interference from frequencies outside the bandwidth of the desired frequency. Thanks for correcting that.

However, there certainly is a thing "Spurious Tones". The definition is :

In electronics (radio in particular), a spurious tone (also known as an interfering tone, a continuous tone or a spur) denotes a tone in an electronic circuit which interferes with a signal and is often masked underneath that signal. Spurious tones are any tones other than a fundamental tone or its harmonics. They also include tones generated within the back-to-back connected transmit and receive terminal or channel units, when the fundamental is applied to the transmit terminal or channel-unit input.

If these tones are generated in the transmitter, then they could appear in the baseband signal of the receiver, and cause unpredictable side effects when decoded.

The majority of definitions for Spurious Frequency, suggests that this term is primarily used for interference developed in a superheterodyne receiver. Basically it means that more than just a single frequency can be received by a receiver. The most obvious being the desired signal, is equal to the the Local Oscillator (LO), plus the Interemdiate Frequency (IF), and the second is equal to the (LO), minus the IF. This is the type of interference that is attenuated by RF filters on the receiver.

Top