I can hear my Wifi card on my TV!

Move the AP/client further from the TV/antenna, change the WiFi channel, or get a TV that's not so susceptable...

Reply to
William P.N. Smith
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As the subject really. It sounds like the interference from a mobile phone but with longer pulses.

Reply to
fishman

I can hear my TV on my wifi, and see it too ;)

might try plugging your ap into different 120v outlets, maybe if its not on the same circuit the noise will go away.

Reply to
bumtracks

Swell. I have to reconfigure my news reader to display the subject so I can figure out what you're talking about. Instead of reminding me to read the subject line in the body of the message, it's so much easier to just repeat the subject (in greater detail) in the body of the message.

The TDMA/GSM/IDEN RF pulses from a cell phone are somewhat similar to the beacon broadcasts from a wireless access point. They have a different repetition rate, but they all generally sound the same. Your TV is rectifying some of the RF. Since you didn't mention anything about the TV picture, I'll assume that it's an audio only phenomenon. It's probably the audio circuitry in the TV that's doing the rectification. You could just move the access point away from the TV and eliminate the problem. Or, you could find the point of entry and apply some shielding or RF blocking ferrite beads. It could be coming in via some of the audio amplifier phone cables, especially if the TV has a high gain phono (turntable) input.

Reply to
Jeff Liebermann

It's not a major challenge, just an inconvenience. I have Forte Agent

2.0 set to not display the header when displaying the message. This gives me more room to work, primarily so I can more effectively plagerize web pages and usenet postings. To display the header, I just right click, and select "Show Header Fields". When done, I have to do it again as it's a toggle.

In the distant past (1987?), when I was shoveling usenet news via Bnews at 2400 baud, paid for connect time by the minute, and there were perhaps 100 newsgroups, economy of content was important. Signatures were limited to 4 lines. The amount of quoted text was severely restricted. Salutations were discouraged. Subject lines were not repeated in the body. The idea was to reduce the number of bytes in each message. Today, we have flat rate service, multi-megabloat bandwidth, and headers often larger than the message body. I guess this is called progress. Some of the habits of economoy that made good sense in the 1980's no longer make much sense. Non-repetition of the Subject line is one of those.

Basically, if you expect someone to spend the time to answer your questions, make an effort to provide them with sufficient data to make a suitable guess, and make it easy for them to read. Obstacles are irritating.

Was it "heard" on all channels or just some channels? Audio only? Through a VCR, Tivo, or DVD player?

Atmospherics or location sensitive interference are a possibility. However, I predict that it will be back, usually in the middle of an important show. If it fixed itself, and it was audio only, my guess is a loose connector, where the center pins made a connection, but the shield was lacking.

I've been doing that for quite a while. The address is my palatial office. The only problem is that someone occassionally calls to get a question answered. Usually, they're desperate (work related). I try, but it usually burns too much time. Sometimes, they send money (or paypal). The telemarketer will call anyway as I'm also listed in the phone book.

I consider it good form to know with whom I'm talking. Try wearing a mask in public and see how people react. Tell them you're acting anonymously due to fear of identity theft. I consider myself responsible for everything I say and post. I also don't consider hiding behind a mangled email address and signature to be a great example of spam fighting.

Anyway, I hope this has explained a few things. I would move the access point away from the TV.

Reply to
Jeff Liebermann

This is gonna sound like hair splitting but....

Actually, entry via the power line is quite possible. Long ago, I did some type acceptance and type certification tests on a contraption that had a noisy switching power supply. We installed an unshielded pair of RF chokes at the power line, a disk ceramic across the line, and an MOV (because it was a convenient place to put it). That eliminated the conducted and radiated junk from the power supply.

However, we then started getting reports of radio station (FM and TV) pickup that were not present before the chokes were added. It seems that the chokes were great at 100KHz, where the power supply operated, but not so good above 100MHz. Instead of blocking the RF coming in via the power line, they would re-radiate it to the nearby sensitive circuitry. Rather than apply yet another band-aid, I elected to find the point of the RF sensitive circuit that was causing the problem. A few ferrite beads and bypasses eliminated the problem.

Todays TV's and Hi-Fi's are RF similar. The circuitry has little RF bypassing and can pickup and rectify at almost any frequency. Xsistors and IC's have much more gain at high frequencies than older devices. The only saving grace is that the leads are MUCH shorter than older discrete component designs, and therefore pickup less junk. (Wires radiate and pickup, components do not.) However, at 2.4Ghz, the traces and wires are electrically large and act as wonderful antennas.

I would say that there's a small chance that the 2.4GHz arrived via the power line and was rectified by something, causing the noise. However, it's much more likely that it entered via an loose phono or coax connector.

I'll add some more hair splitting. Semiconductor devices rectify RF based on the square law diode curve. Therefore, the rectified voltage would decrease with the square of the applied RF, which decreases with the square of the distance. Move twice as far away and you only get

1/16th the detected DC.

More power to you. This paradox is one that the FCC will need to deal with eventually. In addition, ham radio operation on 2.4Ghz is a licensed service. Therefore, ham radio has priority over unlicensed wireless. There's also substantial confusion as to what happens when hams are running 802.11 modulation using the ham frequencies. 802.11 is an IEEE specification and not approved or controlled by the FCC. Nice mess. Anyway, I can predict the outcome between a few thousand hams using 2.4Ghz and a few million Part 15.247 devices backed by some major corporations. The hams will lose.

Enough hair splitting as I have little hair left to split.

Reply to
Jeff Liebermann

Today, we have flat rate service,

I'm always amused by the fellow going off on someone for a large signature line, when in the next newsgroup over, someone's uploading the latest and greatest pornfest movie at 700+ meg..

I saw some suggestions that it was coming in through the power earlier, which is extremely unlikely. FAR more likely is a phenomenon called "direct rectification".

Chips, transistors, and diodes all can do this to some degree, and the pulses of RF from a Wi-Fi box are well suited to being detected by this method. The RF hits these semiconductors, and a voltage is developed. This is more or less how the old crystal radios worked. Moving the Wi-Fi unit further away will help a lot, as this is governed by the inverse square law. In short, if you double the distance, you get 1/4 the interference.

Both units are operating under part 15 though, so the interference is just something you'll have to live with if you can't solve it.

The funny thing is that my ham licence allows me to run 1500W of video if I choose to, on frequencies that overlap the Wi-Fi band. It wasn't my decision to co-locate these allocations, but part 15 devices "must accept any and all interference, including that which may cause undesired operation."

Reply to
Dave VanHorn

What's it saying?, and what channel do you get it on?

Reply to
Peter Pan

"Jeff Liebermann" wrote

Thanks for going to the effort of that so you can reply! I think your newsreader software is a bit ropey, if you can't find out what the subject of a message is.

-snip informative reply-

Thanks, I understand now. I can't seem to recreate the problem again, so perhaps it was to do with the atmospherics on the day I first experienced it.

I don't know of many people who put their direct contact details on usenet.

Reply to
fishman

You probably already know that the "H" key will toggle the display of all headers. Marginally faster than the mouse thing...

I was of the same mind till I started getting thousands (yes, really!) of virus payloads a day from some virus that was grepping the newsfeed for Email addresses.

Reply to
William P.N. Smith

Agent displays the subject just fine, but it doesn't waste real estate doing it, and ask yourself, should someone really have to read teh subject line to understand what your posting means?

Reply to
Mark McIntyre

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