+ Reply to Thread
Results 1 to 14 of 14
  1. #1
    Registered User
    Join Date
    11-27-2005
    Posts
    8

    Standard headsets on a 7135?

    I'm about to buy a couple 7135's for me and my wife, but I have a quick question about using headsets. Upon searching I've found the following:

    1. The 7135's headset is 4 conductor, not 3.
    2. The pins are wired [mic, left, ground, right] from tip to base.

    To me, this sounds like normal 2.5mm 3-conductor headset would end up shorting out the right earphone, but would still work.

    Is this the case? Can I use any regular 2.5mm headset with this phone? I'm not against making an adapter if necessary, in fact I have all the spare parts to do so lying around because I tried to do the same thing with my old Samsung x426 (which didn't work because its 4-conductor connector was quite wacky and not spaced properly)

  2. #2
    Cornfused MGuzzy's Avatar
    Join Date
    08-27-2003
    Location
    Sacramento, CA
    Posts
    2,810
    Yes you need an adapter, Here ya go:
    http://pc-mobile.net/ky7135.htm
    Also remember a search for "stereo adapter" in the 7135 forum returns many hits.... Welcome to the forum!
    mg
    Luck is where opportunity meets preparation.

  3. #3
    Registered User
    Join Date
    05-16-2005
    Posts
    299
    I made a standard 3.5 mm (1/8 inch) 3-circuit headset to Kyocera 2.5 mm 4-circuit adapter using standard parts. However, I had to reduce the diameter of the 2.5 mm plug to properly fit the Kyocera jack (see page 3 of thread "1/8 inch to stereo adapter"). Also, it only adapts the headset and does not have a microphone or switch. So, if a call comes in while you are using it, you must unplug the adapter to answer the call. There are other adapters available both with and without microphones. However, most of them are wired for ground on the base rather than on the third ring. This typically only causes a problem with the balance adjustment. The adapter from PC-Mobile, referred to by MGuzzy, is the only one I know of that is specifically for the 7135.

  4. #4
    Registered User
    Join Date
    11-27-2005
    Posts
    8
    No, I don't want to use stereo headphones with it, I understand I need an adapter for that.

    Lets say I wanted to use a standard Jabra headset with the 7135, which is 2.5mm, 3-conductor (1 microphone, 1 headphone). Would I need an adapter or will it just work?

  5. #5
    Registered User
    Join Date
    05-16-2005
    Posts
    299
    It will not work. A 3-circuit monophonic headset has one signal for the earphone, one for the microphone, and one for the ground. And, it has only 3 circuits on the plug. The Kyocera headset jack requires a 4-circuit 2.5 mm plug. A 3-circuit 2.5 mm plug will not work. Simply having a plug that is the correct diameter is not enough to acheive correct operation. You must also have the correct number of circuits (4 in this case), and the circuits must connected correctly. Many people have tried to use a 3-circuit 2.5 mm adapter to connect 3-circuit 3.5 mm headset plugs to the Kyocera jack with very undesirable results. This is because a 3-circuit plug shorts out things in the 4-circuit jack that should not be shorted out. If you want to use a 3-circuit Jabra headset with the Kyocera, you will have to have a 3-circuit to 4-circuit adapter that properly connects the Jabra circuits to the Kyocera circuits. The microphone and ground should be connected their proper circuits, and the earphone should be connected to the right stereo audio connection (I am guessing about this because I don't remember for sure which side the Kyocera uses for monophonic telephone audio, but I think it is the right side). Note that if you obtain or create an adapter to do this (i.e., 3-circuits to 4-circuits with a microphone) you will lose one side of the stereo audio when playing MP3s. Also keep in mind the problem I described in getting the plug to fit properly in the Kyocera jack. The large diameter metal base found on most 2.5 mm plugs prevents the plug from seating properly in the jack even if it is a 4-circuit plug.

  6. #6
    Registered User
    Join Date
    11-27-2005
    Posts
    8
    Hmmm. Ok, so shorting out the right earphone makes the 7135 unhappy. This seems like a design flaw, but oh well.

    I can work around physical limitations and such, I was just wondering if I will need to make an adapter or not. I guess so.

    Edit: Actually, I guess not:



    This thread makes it pretty clear that many people are using standard 3-conductor 2.5mm headsets with the 7135 with no problem.
    Last edited by Saturn49; 11-27-2005 at 04:54 PM.

  7. #7
    Registered User
    Join Date
    05-16-2005
    Posts
    299
    Do what you want to do. You can ignore logic if you wish. I have nothing further to contribute. However, I suggest you read BDP's post (page 2) to the "1/8 inch stereo adapter" thread before you proceed.

  8. #8
    Registered User
    Join Date
    11-27-2005
    Posts
    8
    I read that post, and I don't know what happened there. But I count at least 6 people on the thread I posted above that are using standard 2.5mm, 3-conductor headsets with their 7135s without issue:

    AJR (OP)
    ngav (2nd post)
    skibumtx (3rd page)
    DanDiego (4th page)
    Guzzy (4th page)
    TDS (5th page)

    If I kill the 7135 with a normal headset, I'd be very surprised.

    Unfortunately, my local Alltel was out of them, so it'll be Wednesday or so before I can try anything.

  9. #9
    Cornfused MGuzzy's Avatar
    Join Date
    08-27-2003
    Location
    Sacramento, CA
    Posts
    2,810
    Actually I have a number of standard earbud type headsets that I have found to work with my 7135. I have also found many that don't. It seems to be just trial and error. I can usually tell pretty quickly if it is going to "short" the contacts they way the button does when you answer the phone with the OEM Kyocera headsets. Obviously there is no answer button on these.
    For awhile I was on the hunt for a single earbud headset with an answer button and a retractable spool. I found one from a company called GoldLantern but didn't like the quality of the mic pickup, and a generic one that fit a Motorola V60, v66,v998 etc. (I liked that one best but the wire wore out on the retractor). And a non-retractble one with button at a Cingular dealer for a Samsung S307.
    That said I would echo tedcmiller's concern that you have to be carefully. My experimenting has resulted in having to reset my phone to get it back to normal. Happy hunting.
    mg
    Luck is where opportunity meets preparation.

  10. #10
    Registered User
    Join Date
    06-20-2002
    Posts
    180
    Originally posted by Saturn49
    Hmmm. Ok, so shorting out the right earphone makes the 7135 unhappy. This seems like a design flaw, but oh well.

    I can work around physical limitations and such, I was just wondering if I will need to make an adapter or not. I guess so.

    Edit: Actually, I guess not:

    This thread makes it pretty clear that many people are using standard 3-conductor 2.5mm headsets with the 7135 with no problem.
    I've been reading this forum for a couple of years now.
    All too often someone posts about how their phone has gone totally nuts on them after working with a "standard" headset just fine.

    Sometimes a connector's bands are not as wide others (meaning the insulating breaks between them are wider) - and MAY allow operation - at least until things wear a little bit from use, or the connector gets seated to a slightly different depth (like rotating it?). Then things get "interesting".

    Sometimes silicon elements inside of the chip used to drive the audio outputs may be able to handle the dead-short - FOR A WHILE. Then you operate it on a really hot day or in your car before the air conditioning has cooled the interior - or whatever, and the transistors get over stressed and cause a fault. The fault could last as long as power is available, or maybe it won't clear at all. Digital circuits can act VERY strangely and erratically when operated on reduced voltage - as would happen when more than planned current flows through a circuit board trace or a wire or a connector. Or maybe silicon elements get extremely over heated - and when they fail, they damage other parts of the IC at the same time.

    Just because some folks have stated 3 conductor headsets worked for them, doesn't necessarily mean it worked for them in the long term.

    And just because SOME folks have gotten it to work for a long time does NOT mean YOU won't end up with a dead 7135.

    So:
    How lucky do you feel?
    How lucky are you feeling about all of next month?
    And the month after that?

    Put another way:
    Do you have insurance - on Anything?
    If so, then somewhere along the way you've realized your luck in not limitless.


    Now:
    Could they have put in thermal protection or some other means of allowing more common headsets to be used?
    SURE!
    Should they have?
    From the user's point of view: YES!
    From Kyocera's point of view: NO!

    Realize that they want to sell you headsets and headphones as part of their follow on business plan. So they make it a proprietary design and don't publish the specs, so folks will come back to them. And if you damage the phone by playing around with non-OEM accessories - they get to sell another phone, and their accessories too!!

    Nobody said life was fair. And if they did, they were lying.

    One last thing - I recall having read it is the LEFT audio channel that is active during a phone call. But I also recall that some folks were using an adapter or headset meant for some other phone (I think it was a Samsung phone), and that at least one of them realized the left and right audio channels were reversed. That reversal might have been a mis-assembly, or it may be that the phones have a different pinout, and no one paid much attention to it.


    Saturn49 -
    Good luck with whatever you decide. Just be prepared to pay the price if luck isn't with you.

  11. #11
    Registered User thaxman's Avatar
    Join Date
    09-16-2004
    Location
    Tucson
    Posts
    415
    I have a factory Kyo stereo headset for mp3s & when a call comes in, yes, it is the LEFT earbud that operates in mono. The right bud is silent.

  12. #12
    Registered User
    Join Date
    11-27-2005
    Posts
    8
    Well, I got the 7135 today, and yesterday I spent the time and put a 4-conductor connector on my Jabra headset.

    After looking closely at the 4-conductor connector I had and comparing it with the 3-conductor "universal" connector from the Jabra, I can clearly see they are a bit different. The cheapie hands-free set they gave me free at Alltel is a 3-conductor (it specifically says compatible with Kyocera on it), but has slightly different spacing than the Jabra.

    labeled as tip, 2nd ring, 3rd ring, 4th ring:

    the tips on all 3 are the same length.
    the 2nd ring on the Alltel and Mouser are the same size, but the Jabra 2nd ring is longer

    So the Alltel headset will clearly short out the 3rd and 4th ring, I'm not exactly sure what the Jabra would do, and I don't intend to try it.

    My modifications worked fine, though it was a pain to modify the 4-conductor connector to fit the 7135. I ended up using locktite on the threads to keep the housing on, it seems to be working great.

  13. #13
    Registered User
    Join Date
    05-16-2005
    Posts
    299
    At the risk of being repetitive, I really don't understand why people go to the trouble of modifying hardware (in this case a headset) to work with a different interface when an simple adapter will accomplish the same thing. Buying or building an appropriate adapter is usually much more reliable and doesn't result in a device that is useless for anything because the attempted modification was botched or the device it was modified to work with goes belly-up.

  14. #14
    Registered User
    Join Date
    11-27-2005
    Posts
    8
    Originally posted by tedcmiller
    At the risk of being repetitive, I really don't understand why people go to the trouble of modifying hardware (in this case a headset) to work with a different interface when an simple adapter will accomplish the same thing. Buying or building an appropriate adapter is usually much more reliable and doesn't result in a device that is useless for anything because the attempted modification was botched or the device it was modified to work with goes belly-up.
    Oh, in this case I had already modified the Jabra to work with my old Samsun x426, which also used a 4-c cable, except it was wired differently with different spacing. In that phone's case, the 4 conductors were used to keep the earphone and mic separate. If you tried to tie the two "ground" wires together the phone got confused and the headset started to crackle.

    So I simply ripped that 4-c end off and put the mouser one on.

    Otherwise I would've had to put a 3-c connector back on the Jabra, then build a 4-c to 3-c adapter.
    Last edited by Saturn49; 12-01-2005 at 11:38 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts