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What are those gold contacts in the Sim Card and SD card cover?

ADTC

ADTC

Member
Note! This has nothing to do with "contacts" (phonebook, list of numbers) or "gold card" (some SD card modification).

I have a Desire HD, and when I remove the SD/SIM card cover from the back of the phone and look inside it, I find two gold contacts on the left side of the cover. There are also two matching gold contacts on the right side of the phone.

[So ridiculous, I can't find even one picture of the inside of the back cover. I had to take one myself! The bottom part of the photo below was taken by me (explains the bad quality). The top part was from a Google search.]
desireHDcover.png


Initially I thought this is to turn off the phone or disconnect the network when the cover is removed because the SIM card is accessible without removing the battery. (Is the SIM card hot-swappable?) The battery cover also has similar contact, although they are joined, suggesting it will let the phone know that the cover is on (although I have not tested the effect yet.)

But the phone seems to work as normal without the SIM/SD card cover. I can make calls and access the Internet on 3G without any problems or slowness. However, the network signal strength indication in the notification bar was showing mostly 0 and sometimes 1 bar. Once I put back the cover, the signal climbed up to a full 4 bars within mere seconds.

Is this an antenna built-in to the back cover? If yes, how come I can make/receive calls and surf the internet without any problem even without the cover, regardless of signal strength indication being 0?

I know these questions may fall in the category of mundane, but I'm really curious to know why those contacts are there, and what purpose they serve!
 
The name of the cover is HTC Desire HD antenna cover.
HTC Desire HD Antenna Cover #37H00364-04M - eXpansys UK

So you may are right with the antenna :)
Auxiliary antenna in the phone + antenna in the SIM cover + antenna in battery cover ?

EDIT: ... found this
[FONT=arial,helvetica,sans-serif]This Antenna Cover has the antenna connectors necessary for GSM Reception.
[/FONT]
spacer.gif

http://www.htcdirect.co.uk/index.php?main_page=product_info&products_id=998

EDIT: ... found this about the battrery cover :)
[FONT=arial,helvetica,sans-serif]This Battery Cover has the antenna connectors necessary for Bluetooth and WiFi Reception.
[/FONT]http://www.htcdirect.co.uk/index.php?main_page=product_info&cPath=2_73&products_id=993

Harry
 
Harry2 said:
The name of the cover is HTC Desire HD antenna cover.
HTC Desire HD Antenna Cover #37H00364-04M - eXpansys UK

So you may are right with the antenna :)
Auxiliary antenna in the phone + antenna in the SIM cover + antenna in battery cover ?
Click to expand...
Thanks. Well I got the name wrong. But I still am not sure if it really is an antenna that the phone uses. And do phones come with two antennas? Why does Desire HD have two?

Anyway I don't think the battery cover has an antenna. Because there is only one metal strip in the cover which short-circuits the two contacts in the phone.

Antennae require two leads to them for them to work, right? (Similar to a light bulb that has to be connected to both +ve and -ve of the battery to light up) Since there is only one lead in the battery cover, I don't think it's an antenna. Unless the metal strip can somehow be used as an antenna, but I doubt that's possible.

EDIT: Oh oops! I just saw your edits! Great finds!!

EDIT: Yea I tested it out. When I force my phone to 2G and removes the "antenna cover", it loses network completely. When I force my phone to 3G and removes the cover, it connects to 3G but the network signal is shown as 0 (despite having very responsive network). Once I put in the cover, it shoots up to full.

It seems the GSM antenna somehow enhances the 3G connection, but how?

And I have to find a reliable method to test the battery cover antenna because the battery will just fall off. Maybe blutack it or something before removing cover. Lol.

EDIT: The battery cover does affect the WiFi and the Bluetooth as the phone is unable to find any networks or devices once the cover is removed. I tested this, but forgot to update it here earlier.
 
Ok, so I just got the Desire HD but my antenna cover seems to have taken a bit of a walk. I have lost all signal strength and can barely make a call. I was about to take the phone back as a factory failure but now that I see this I guess Ill just get a new antanna cover.

This should sort my problem right?

BTW: Amazing phone and I love Android!
 
RandomGRK said:
Ok, so I just got the Desire HD but my antenna cover seems to have taken a bit of a walk. I have lost all signal strength and can barely make a call. I was about to take the phone back as a factory failure but now that I see this I guess Ill just get a new antanna cover.
Click to expand...
The 3G antenna is built-in the phone. Only the 2G antenna is on the SIM card cover. Since you just bought your phone, I suggest take it in for warranty as your problem could be a manufacturing defect. But I hope you have replaced the covers firmly and correctly as per user manual instructions, and not broken anything during the process. (Of course, you can purchase and try a new cover, I'm not against it :D )
 
My battery cover is fine. Its the antenna cover thats missing. I havent broken anything. Not sure if they will accept it back like this but Ill still try. Specifically since Im in South Africa and despite the phones arriving, we have no accessories whatsoever so any spare parts will only arrive within the next month...

Anyways, I cant understand how they can possibly blame me. One second the cover is on, the next second I look down and its gone??? There have been many reports regarding the flimsy build quality. I hope they give me a new device but im not holding my breath.
 
It seems you have lost your antenna cover. I'm not sure if loss of parts are covered in warranty, and I'm guessing they are not (otherwise we could 'lose' parts only to sell them later on ebay while getting free replacements).

Anyway as for the flimsy build quality, that seems true but my antenna cover seems to be just fine as long as I don't pull it out or anything. I don't see how one can lose it so easily unless one forgets to push it in until it clicks.
 
My girlfriend just got a hd.. I took the antenna cover off for her. Broke it, its really flimsy. :(
 
I lost all audio on my DHD, except I could still hear phone conversations once I answered the call. To clarify, I could not here the audio of: media files, key strokes, games or ring tone if someone was calling me. If I was in a call I could have a conversation fine and the speaker phone worked as well.

I 'fixed' this by cleaning the metal contacts on my battery cover. I just scratched the contacts clean with a flat head screw driver.

Also my phone died on me in the middle of the day with a full charge. I could not get it started at all. I tried cleaning all the metal contacts I could find under the sim cover and battery cover but it did not fix the problem. I removed the battery and re-seated it and it did not fix the problem. Once I cleaned the battery contacts with a screw driver the phone started.

I think that the metal contacts in this phone a very prone to either corrosion or dirt gathering which impedes their operation. If you have any problems with this phone, clean the metal contacts before you take it in for repairs.

Regards,

Gweeeep.
 
Thanks for the heads-up Gweeeep! I haven't had both your problems at all, yet anyway.

But I'm a bit concerned about using a screw driver to clean the contacts. I would rather use a soft cloth (or tissue) and a metal polishing liquid* (or WD-40), which I have done before for my laptop's Ethernet port. It was not in use for a very very long time, so when I wanted to use it, I had to clean the contacts before I could get it to work.

* Do not rub too much with metal polishing liquid, it rubs away a layer of metal from the surface. If you keep doing it, eventually you'll hit the bottom!
 
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