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Full/Half Duplex
noddy595 Jul-11-02 05:42 PM
How do I check to see if my sound card and modem have full duplex or half.

Sound card is C-Media Cm 18738c3dx pci
Modem is Topic 56k Data Fax Voice Modem.

Any help would be appreciated, this is my first post on this medium.

1. RE: Full/Half Duplex
lbyard Jul-11-02 07:24 PM
In response to message 0
Kind of hard to say without knowing what the operating system is. Larry

2. RE: Full/Half Duplex
noddy595 Jul-11-02 10:29 PM
In response to message 1
Sorry about that...using Windows ME.

3. RE: Full/Half Duplex
lbyard Jul-11-02 11:34 PM
In response to message 2
Sample Champion (http://www.purebits.com/index.html) may answer the first question. I have not tried it.

See if MODEMDoctor (http://www.modemdoctor.com/html/win95.htm) answers the second question. Most modern MODEMS and ISPs should be running full-duplex.

Perhaps a better approach to this would be to state the problem. Larry

5. RE: Full/Half Duplex
noddy595 Jul-12-02 08:53 AM
In response to message 3
Thanks for the prompt response. I will try the sites you recommended.
My problem is I talk to my relatives in England using Yahoo voice chat,and we cant talk at the same time(like on the phone). In reading various articles they say check your sound card to see if its configured for Dual or Full Duplex mode. I downloaded the manual for my sound card from the manufacturer but this was no help.
The modem question was more of a maybe that "could be the problem " and also if their is a option for Half/Full duplex how do I configure it.
Again thanks for your help. Tony

6. RE: Full/Half Duplex
lbyard Jul-12-02 12:32 PM
In response to message 5
I do not know where you are located, but if you are in the U.S., the delay caused by the time for a transmission to travel that far may have something to do with it. Larry

7. RE: Full/Half Duplex
noddy595 Jul-12-02 09:08 PM
In response to message 6

It doesn't matter whether the person is 5 miles away or 5000.In Yahoo voice chat I am in Half duplex mode...I talk, you list, then you talk I listen. The Yahoo voice chat help page gave the following:

1. Click on the Windows "Start" button
2. Double-click on the "Multimedia" icon
3. Select the "Devices' tab page.
4. Expand the "Audio Devices" and select the appropriate sound card.
5. Then, click on the "Properties" button and configure your sound
card to use dual or full duplex mode.
6. Clicl "OK" until all the dialog boxes are closed.

The problem is with step #5.When I click on "Properies" all that comes up is the general tab.As you know, there is no choices on the general tabs.

I have gone on variuos sites and all that I can find is a description
of what half/full duplex is, I know what it is. The info I have got from the manufacturer sez I have a full duplex sound card, I cant find out how to verify this, or if I want to, change any options.

The same apply's to my modem. It is a Data/fax/voice modem,but how do you change any options. It also could have a half/full duplex option,but how do you get into these options to change them.

Most applications/programs, you have pages and pages of options that you can configure to suit your personal requirements.

Again, thanks for the help.

I live 70 miles north of London, Ontario, Canada and am a retired telephone emloyee.

9. RE: Full/Half Duplex
lbyard Jul-13-02 07:12 PM
In response to message 7
I donít think that has anything to do with the MODEM except possibly speed. Part of that 5,000 miles may matter, the part between you and the ISP/telephone switch. How far is that? If the MODEMs at both ends can do full-duplex given your local conditions, they will. Most will. And most will operate above 33 K when the telephone line is clean and does not exceed 4 miles or so and will operate at 33 K when it isn't good or is much longer. You might want to try this: http://808hi.com/56k/3comline.asp. To answer your question, the half/full duplex is probably done with a Hays MODEM string. Details on that are probably in the MODEM documentation. The generic Hays codes are also widely available on the Internet. One does not usually fool with the full/half setting, or at least in recent years (or since about the time of 2400 bps MODEMs) I have not found it to be necessary. My sound card (SoundBlaster Live) has more tabs, but no half/full duplex settings. The setting may be in the software that came with your soundcard? Larry

10. RE: Full/Half Duplex
lbyard Jul-13-02 07:24 PM
In response to message 9

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