[droctii]

I am getting some type of intermittent 'radio' interference when I am using my 7280. The interference sounds very much like when you put an electronic device next to a TV. Sometimes I don't hear it, but the person on the other end hears it. I called customer service for T-Mobile, but they didn't have any reports of this matter. When I visited the T-Mobile store, one of the guys said he gets it some times with his Side Kick. Not sure what to make of it. Any ideas?

[headtailgrep]

This is standard interference with all GSM/GPRS devices..

they will all do this. What happens is the broadcast of signals on your GPS/GPRS device is powering any nearby speakers to emit a sound..

the closer to the speaker, the louder the sound.

This works with just about any device that has speakers. All phones have a speaker built in and will cause the same interference.

It's not just blackberries..

[yahtzee]

My 7510 does it when its placed near a polycom speakerphone.

[droctii]

Originally Posted by headtailgrep

This is standard interference with all GSM/GPRS devices..

Thanks for the responses. However, I never experience this problem with my Nokia 7250. I am also surprised at how low and poor the sound quality of the unit is.

I really like it, but the whole sound issue and buzzing is just a bit strange to me, having done GSM/GPRS on other phones before the Blackberry.


O well...

[headtailgrep]

trust me.. all phones have SOME interference... with GSM/GPRS devices, it doesn't matter who's phone you are talking about, put it right next to the magnet of a speaker (or within a good distance) and you will hear the same tones.

Some devices broadcast with more or less power than others, but the will all create the same interference..

Here's something: Take any blackberry, put it next to a CRT monitor.. when an e-mail comes in, you will see your screen go wierd for a second. The old 957's and new blackberries all cause the same interference..

[droctii]

Ok, I agree with you once you are unders such conditions (ex. near to a TV or something like that). I was talking about just driving in my car or simply walking outside and talking without 'knowingly' being around anything that should cause such. I didn't experience this type of behavior on my Nokia phones.

Anyway, I'm not going to lose sleep about it at this stage. Most times it's the people on the other line that are affected. I have thought that maybe my headset was the picking up the signal interference.

[Skive]

Its just interference and no two phones seem to get affected exactly the same as everyone else, have you tried moving your blackberry around in the car to see if that makes any difference to it?

[Mark Rejhon]

That's strange. Some people say the BlackBerry has some pretty good sound; while others say it has pretty poor sound.

Try going to a cellphone store and asking to try the voice quality of another BlackBerry at the store; and see if it is normal or not;

Although interference will always be an issue, sometimes speakers are defective (i.e. more sensitive to interference than other identical units).

It is also much less of an issue if you are in an area of strong reception. If you are in a weak-reception area, the powerful 2-watt transmitter in the 7280 will probably provide more interference within fringe areas; but that is better than a dropped call;

Try comparing two BlackBerries and seeing if it is typical or atypical (worse than average).

[droctii]

Well folks, after thinking that I had bought a 'lemon' on Ebay, I decided to email the guy that I bought it from and put him on the witness stand. He confessed that he'd only used it for one week and that it was working well. Yeah, sure! I thought.

Anyway, tonight I spoke to two friends of mine who were fellow T-Mobile users. One lived here in town (using a Treo 600) the other live in Conneticut (using whatever handset). Both reported similar problems- the periodic buzzing in the phone that was a pain in the butt. This put to rest my suspicions about my BB 7280.

I put in yet another call to theT-Mo people and finally someone was able to 'help' me. He said that it was probably the GPRS updating on the phne that made the noise. Wow, this finally made sense, because I didn't get those problems when I put a SIM card from another provider in my BB, nor did i have it when I put the T-Mo SIM card in another phone (Nokia) that isn't set up for GPRS.

Of course, i asked if there was anyway to turn GPRS off while I used the phone, as people complain about how bad my phone sounds ("Hey, you need to get a new phone", etc.)

Well, does anyone know if it's possible to temporarily disable GPRS and use regular GSM to use the phone without the interference?

[sting0r]

Not sure that makes sense to me, when I am on the phone I can't receive any data via GPRS. I know there are some devices out there that can send voice and data at the same time, but I am fairly certain the BB isn't one of them. I haven't been able to find a way to force the phone into GSM only mode.

[droctii]

Well I think it's just T-Mobile's terrible service for GSM (voice calls). Perhaps one of the people who work for them that hang around here can weigh in.

[EvoL]

It sounds like the LCD screen interferance that some have encountered when the backlight is engaged. It is a known issue and would be covered under the standard 1 year warranty. You should contact RIM if you bought your BB from a private party. The warranty should be transferable.

As for disabling GPRS, that would involve removing all of the data service books. Only problem is that would also remove you ability to access the internet as well as any pushed emails. SMS and voice would still function the same as they use the GSM network solely. My advice would be to check under settings/network or HML Hosts for an option to disable GPRS during Voice Calls if you find that to be the culprit.

[droctii]

Now I've been investigating this thing a bit more. It seems as though the problem mainly occurs when I use the handsfree earpiece ( I've got 3 of them- 2 by Jabra). It's weird and frustrating because I get headaches when I put the phone directly to my head.

For you science buff out there, what unique signals would the handsfree unit pick up?

[Gothalyptic]

I get the same thing on my corded earbud. I think it still follows the same principle of the RF inference. without going into RF theory, I'll just say the earbud, and any other handsfree corded device will in fact act as an antenna, conducting the RF electricity right into the first thing it hits, unfortunatly, most of the times it's the microphone, therefore the person on the other end will hear it, while the person using the device may not.

RF unfortunatly has harmonics, usually right around double the wavelength. If you, say transmit on an amateur radio band of 147.015, any radio receiving on the 300mhz band may in fact pick up the harmonics, while not really making out the speech, the "bleedover" if you will, will be picked up. This is the exact same reason phones will cause CRT monitors, and speakers to go nuts for a bit while the transmitter is transmitting. A handsfree will also pick up these harmonics, essentially, again the handsfree piece is acting as an antenna, a full wavelength 800mhz antenna is surprisingly the same length as, you got it, the handsfree piece. Again, harmonics. Your best defence is to place the blackberry to your left (or right side, depending on preference), route the wire around your back and to the oppisite side of your body. This will put a "insulator" of sorts between the "antenna" and the device. Another idea to do, is hit radio shack, or other electronics hoby shop, and pick up an RF Magnet, what this does is goes around the wire, a few coils and the magnet will then absorb the RF rather then the microphone or ear piece. While it doesn't look pretty, and I've never tested this, however RF Theory says it will cut out the problem, if not elliminate it totally.

It gets a bit trickier when the phone (which most do) is a full duplex model, it transmits on one frequency and receives on another, now you theoretically have 2 harmonic interferers to deal with, though the receiving band isn't that much of a problem unless you stand right under the transmitting tower.

Have I mentioned I enjoy my amateur radio license? lol it's a wonderful asset with the RF theory classes I took as a side note.

Hopefully this helped clear up a few things. It's mainly harmonics, which are hard to combat, especially if you have no way to alter the power level.

case and point as a little story. I am a volunteer firefighter/emt, as well as a ham operator. I have a 2meter rig, a 70cm rig, and a 1.2ghz handheld in my vehicle with a tri-band external antenna on the roof for all three bands. I also have a mobile rig for firepolice and ems which operates on the 155, and 440 ranges, both of which fall in the 2m and 70cm range as far as wavelengths go. If I transmit high power (50 watts) on the firepolice mobile, I will literally wash out my handheld ham unit, literally turning it off and rendering it useless until I stop transmitting. On the other hand if I transmit low power on my handheld ham unit (0.5 watts) I will "bleed over" on my firepolice radio as well. The only combat to this, seperation and insulation between the antenna's, so one is now on my rear bumper on my geo, and the other is on the hood, it helped greatly. This is why I advise to route the handsfree behind you, it'll help insulate, even though your body is a conductor to RF, your clothing isn't and provides plenty of insulation for RF at that low of power.

ok I'm done with my rant, just wanted to help clarify a bit, hopefully this helped, if not I can try to break it down a bit better.

[droctii]

Thanks for the lesson I wasn't too bad at physics so I didn't completely miss what you were saying (most...but not all!!)

Anyway here's a few questions for you:

1) Why Me, Lord? (ha!)
2) How did you personally solve your problem?
3) Do you think that the 'faux' bluetooth (ex. jabra bt 200 or 250- can't remember which model off hand) would suffice?
4) About how much of the coil from R.Shack do you think would suffice?

Thanks!

[Gothalyptic]

1) I don't know, maybe you did something bad in your past? lol
2) Got the Jabra BT200 BT easy speak
3) Yep, helped me
4)they're about $5usd but trust me, when I said it won't look pretty. I meant it will look down right funny ;) they're small but still not esthetically pleasing.