TV antenna signal problem

[WI_Bowhunter]

Brand new Puma 30DBSS. Ok, Tv will work normal off the antenna until I turn certain lights on. It seems that all LED lights on the ceiling that cause the TV to lose signal from the antenna when these lights are switched on. Any ideas? They are factory installed LED lights. The TV is a Visio that I installed.

[Peg_Leg]

I agree about the surface mount caps being small, like trying to work with fly poop. I used to put .01 microfarad disc caps across the power leads, still effective but easier to work with than those things you can't hardly see.

[SCVJeff]

No diodes.. The problem is that in order to regulate the voltage to keep constant illumination and to protect from over voltage and burnout.. And it's those switching regulators that are causing the problems with the power leads themselves acting as antennas radiating all this wideband noise that is killing radio and TV receivers, as well as VHF Wx and amateur radio receivers. The fix is to remove these switching regulators and just current limit them with resistors. The are regulators out there used for RC aircraft that are very very clean (they have to be), but they're ~$30 ea.

[westend]

SCVJeff wrote:
All of them that I've played with are generating RFI into the antenna directly.

Are you saying the diodes, themselves, are generating RFI or the regulation circuit?

FWIW, I'm using Asian, non-regulated LED panels, a mix of 36 or 48 3528's and the newer 5050 panels. My float voltage is 13.2-13.6v, depending on charging source. I had thought of using a linear regulator for the lamp circuits (actually an easy thing to do with my layout) but all the panels are still functioning and I don't experience any detrimental RFI. I have my own DIY UHF antenna and a dipole for radio.

[SCVJeff]

All of them that I've played with are generating RFI into the antenna directly.

[MNtundraRet]

The short answer is don't use the lights when watching TV. You could try using a light farthest from the TV. If that works try the nest farthest one. Some may work because of distance.

Messing with the lights will cost money and may be futile for some.

[SCVJeff]

camperpaul wrote:

RoyB wrote:

The other problem is the manf are within the FCC limit rules for creating RFI that may interfere with your other electronics.
Roy Ken

Part of that problem is the regulations (Part 15) concerning incidental radiation are decades out of date.

I'm sure 'LED' wasn't even a decipherable acronym last time anyone was revising Part-15

[camperpaul]

CT_WANDERER wrote:
I installed LED's light in my MH this spring. Put in 14 LEDS. I only have one set of lights that causes problems with my OTA TV. Most of the time I use Sat TV. The light over the dinning table has three DB contact LED's. I tried put aluminum foil around the light (as a light shade) and the OTA TV came in. Not sure if this is a way to work around this problem or not. But if I remove the foil I lose the OTA TV. Putting the foil back on and it comes in again. Most of the time I use the Sat, so it is not really a problem for me. Just thought I would pass this along. Gary

It is not the "magic bullet" but it is valid.

The foil is acting as a Faraday shield and attenuating the radiation from the LEDs.

[CT_WANDERER]

I installed LED's light in my MH this spring. Put in 14 LEDS. I only have one set of lights that causes problems with my OTA TV. Most of the time I use Sat TV. The light over the dinning table has three DB contact LED's. I tried put aluminum foil around the light (as a light shade) and the OTA TV came in. Not sure if this is a way to work around this problem or not. But if I remove the foil I lose the OTA TV. Putting the foil back on and it comes in again. Most of the time I use the Sat, so it is not really a problem for me. Just thought I would pass this along. Gary

[camperpaul]

RoyB wrote:

The other problem is the manf are within the FCC limit rules for creating RFI that may interfere with your other electronics.
Roy Ken

Part of that problem is the regulations (Part 15) concerning incidental radiation are decades out of date.

[SCVJeff]

I didn't have any beads that would fit, so I was only doing caps. But the biggest difference was imply twisting the powerleads from the base of the DC-DC conv. Not completely gone perfect but a huge difference. With balanced power and a few caps Those results were shared with Greg over at Starlights

[camperpaul]

Adding to my previous post:

The garbage level was measured at 14.300 MHz (20 Meters).

The LED assembly used was similar to this one:



I discussed this at length with Jason Weaver, CEO of STARLIGHTS Inc. about a year ago but he dropped the ball because he didn't want to invest in the engineering and tooling to change the current product line.

Because of my involvement with SATERN (the communications group for The Salvation Army's disaster response team) I can not tolerate any amount of interference. Some of our operators in the field are using 5 Watt portable radios (Yaesu 817ND) and we are regularly talking over distances up to 2500 Miles.

Paul - K9ERG

[camperpaul]

I tried using:

1. Just the chip caps

2. Just the ferrite beads

3. Combination of chip caps and ferrite beads

Configuration 3 gave the best results but the garbage level was still over S9
(measured using Icom IC-735 and a dipole antenna 15 ft from the LEDs under test).

When I replaced the 'buck-boost' regulator with an LM317 linear regulator the garbage was completely eliminated.



When V(in) is in the range of 11 to 37 volts there is no change in LED current or brightness.

Paul - K9ERG

[SCVJeff]

For all the tech types..

Here is a wide shot of the FM band, 2mtr VHF, etc. on the left, and a few DTV's up at the top of the screen. This analyzer is plugged into the batwing on the roof.


This is a shot off the same antenna with the patio light turned on.


Thats allot of garbage to filter out.

[RoyB]

What Paul K9ERG has already played with is using real small 1/4-inch or smaller ceramic chip capacitors and soldering across the end of sockets something like this photo. Having very short leads is the trick. Not sure AARL manuals will help much here...

I don't have that much patients anymore at my age... The standard ferrite beads don't work here where the 12VDC connections are made at the board edges... That has been all I have played with and didnt have any success.

Paul had much better luck with the very small chip capacitors.






Roy Ken