|
Welcome to the GSM-Forum forums. You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. Only registered members may post questions, contact other members or search our database of over 8 million posts. Registration is fast, simple and absolutely free so please - Click to REGISTER! If you have any problems with the registration process or your account login, please contact contact us . |
|
Register | FAQ | Donate | Forum Rules | Root any Device | ★iPhone Unlock★ | ★ Direct Codes ★ | Direct Unlock Source | Mark Forums Read |
Sony Ericsson Hardware Repair Post here your Hardware Repairing Hints or Problems with SonyEricsson and Sony Phones. |
| LinkBack | Thread Tools | Display Modes |
03-20-2017, 16:20 | #1 (permalink) |
Junior Member Join Date: Mar 2017
Posts: 14
Member: 2697615 Status: Offline Thanks Meter: 0 | Sony Xperia Z3+ GSM Antenna question (E6553) The model number is E6553, and the GSM antenna is unlike the 'normal' Z3 model which I have plenty of access to. Unfortunately I don't have an extra Z3+, so I would like to ask a question to clarify if there's a problem with the frame as I suspect. The device performed perfectly from new, and as time went on it became harder and harder for it to connect and maintain a GSM datastream. It would lose signal, and disconnect during calls - and get worse over time. I opened it up, and it looks fine - though the springs at the bottom had set a bit. I measured the resistence between the antenna center connection and ground and found it to be 0 ohm. I then lift the antenna pcb - and it rises to infinity on my meter. The springs were bent out a little, to ensure a good connection to the frame as the glass above it was moving in and out. Can anyone confirm that the GSM antenna resistence should be 0 ohms on a Z3+ - the 0 ohm are also present on the main board when the cable is connected, etc. The device is capable of receiving GSM, it's not perfect, and I do realize there's a large loop for the RF signals to do their thing. It's just the first time I have ever seen a truly shorted (0-ohm) circuit. Some pictures, 0 posts = no linking allowed, can be provided upon request - sorry.. Thanks in advance - I hope you can help to clarify if I need a new frame or the Z3+ is supposed to be this way |
03-24-2017, 16:29 | #12 (permalink) |
No Life Poster Join Date: Jun 2003 Location: KA , Deutschland Age: 47
Posts: 631
Member: 32168 Status: Offline Thanks Meter: 183 | The 0 rezistance is not abnormal in that area...because if you connect antena is like a closed circuit....and also in PA and Antena switch are some coils and filters on the output...maybe this is the reason that you find always 0 Ohms....just look for contacts between antenna and connector...or maybe just take out the connector for external antenna and jump it...but look better to not put on ground the "hot pin " ... regards |
The Following User Says Thank You to jan_gabriel2000 For This Useful Post: |
03-27-2017, 10:58 | #13 (permalink) |
Junior Member Join Date: Mar 2017
Posts: 14
Member: 2697615 Status: Offline Thanks Meter: 0 | Thanks for your reply jan_gabriel2000 I have worked on RF systems before, and I know they can trick you easily. What I find strange on this Z3+ is that the RF output is essentially looking into a short (this short being at DC). Perhaps the impedence at the right GSM frequencies are 50 ohm, and the short filters out unwanted harmonics. (I'm missing some test equipment here to verify this on my own) Can anyone confirm my thoughts? Thanks! |
Bookmarks |
Thread Tools | |
Display Modes | |
| |
|