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Posted: Thu Jan 24, 2002 2:57 am
by OX
I have purchased a BD6676 jedi headset adapter and replaced the internally threaded jack with a standard stereo 1/8" jack and need a schematic for the headset that plugs into that jack.
I've discivered that if you short out the true speaker wire to the shield then the radio keys up and the mic works fine. I have a feeling that I need a capacitor or resistor in my headset somewhere. Anyone know what these pinouts are?
Posted: Thu Jan 24, 2002 6:29 pm
by mike38015
I had one of my electronic guru friends try the same thing as I was trying to avoid buying the right ear piece from the big M. It made no difference whatever he did, when ever I plugged in a strandard ear piece the mic keyed up.
The long and short of it, I now own a OTTO Communications ear piece #V1-10174 for $35.00 and it works great.
http://www.ottoeng.com/cgi-bin/commpric ... arPhoneKit
Posted: Thu Jan 24, 2002 7:28 pm
by OX
I've never liked Motorola's prices on common parts. There's no need to pay $75 or more for a headset that does the same thing as a $20 headset. I even checked your link and $75 was the cheapest they sold a headset/boom mic set. Besides, the headphone jack was broken and I wasn't about to pay more high prices on a $1.50 replacement part. It can be done.
Posted: Thu Jan 24, 2002 7:43 pm
by mike38015
I tend to agree, I hate to buy from the almighty M unless I am left no choice. All I needed was the ear phone so I could monitor during meetings and such without it being a disruption.
It mystified my friend that he couldn't Isolate the problem and make a regular ear phone work without causing the radio to transmitt. He was convienced that it had something to do with the screw jack and a ground of some sort to isolate the transmitt terminals, but replacing the jack made no difference.
Best of luck, if you are able to make it work it would be nice to have it posted here for all to see.
Mike
Posted: Fri Jan 25, 2002 5:09 pm
by Will
I have the road map for the adaptor, but not in computer format.
I made a short cable with the threaded 3.5mm plug on one end and a standard 3.5mm jack on the other end. You need a 1.0uf capacitor in series with the center pin on the radio plug end going to the ring contact in the jack.
The ring on the radio end goes to the center contact in the jack. This way you can use any standard headset or earphone.
The threaded 3.5mm male plug is available from Twitco for $2.50
The Motorola threaded accessories key the radio by shorting the earphone/spkr line to gnd thru a 56 ohm resistor.
Center pin===== audio out and gnd to PTT
Ring========== mic line, switch in jack tels radio an external mic is plugged in
Sleve==========ground
In the adaptor is, two diodes, 3 resistors, 6 chokes, and 5 capacitors. All surface mount.
Posted: Fri Jan 25, 2002 8:58 pm
by OX
On 2002-01-25 20:09, Will wrote:
I have the road map for the adaptor, but not in computer format.
I made a short cable with the threaded 3.5mm plug on one end and a standard 3.5mm jack on the other end. You need a 1.0uf capacitor in series with the center pin on the radio plug end going to the ring contact in the jack.
The ring on the radio end goes to the center contact in the jack. This way you can use any standard headset or earphone.
The threaded 3.5mm male plug is available from Twitco for $2.50
The Motorola threaded accessories key the radio by shorting the earphone/spkr line to gnd thru a 56 ohm resistor.
Center pin===== audio out and gnd to PTT
Ring========== mic line, switch in jack tels radio an external mic is plugged in
Sleve==========ground
In the adaptor is, two diodes, 3 resistors, 6 chokes, and 5 capacitors. All surface mount.
Excellent! I was very close. I figured out how to get either Mic in or Speaker Out without activating the PTT but not the capability for both. I saw a schematic for a GP300 headset adapter and figured that I needed a capacitor or something but wasn't sure which yet.
I ordered a CP-3535-ND 3.5mm stereo audio jack from Digikey for $1.04 which happens to perfectly replace the threaded Moto jack and I'm just going to reqire my headset to match the adapter. Otherwise I was going to make a patch cable like you had.
Thanks, I will wire it up and if it works then I'll make a JPG for Bat (with proper credit)
Thanks
Posted: Thu Jan 31, 2002 10:34 pm
by OX
I've got the schematic for this drawn up now and will be sending it to Batlabs but if someone else needs this in the meantime, send mail.
Thanks to Will for the explanation.
<font size=-1>[ This Message was edited by: bubbasnest on 2002-02-01 01:35 ]</font>