Telephone Line to Soundcard - Need Help

[[email protected]]

Anyone know how-to make a cable that would plug into my telephone jack
and then into my computer soundcard?

I bought one from EBay and when I plug the cable into my phone line and
then into the soundcard my line
goes dead.

One guy mentioned he uses an isolator circuit of some sort to not short
out the line in his device.

This is the one I bought below that doesn't work.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=14960&item=5774136958&rd=1&ssPageName=WDVW

**********

This one below supposedly works with a soundcard and phoneline.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5769614109&rd=1&sspagename=STRK:MEWA:IT&rd=1


If you can help send an email to [email protected] o m

 

[Jim Thompson]

Anyone know how-to make a cable that would plug into my telephone jack
and then into my computer soundcard?

I bought one from EBay and when I plug the cable into my phone line and
then into the soundcard my line
goes dead.

One guy mentioned he uses an isolator circuit of some sort to not short
out the line in his device.

This is the one I bought below that doesn't work.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=14960&item=5774136958&rd=1&ssPageName=WDVW

Obviously, there's no isolation. The PC ground connection hoses your
phone line.

This one below supposedly works with a soundcard and phoneline.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5769614109&rd=1&sspagename=STRK:MEWA:IT&rd=1

That "barrel" most likely contains a transformer.


...Jim Thompson

 

[Dmitri]

If you are into making things yourself, here is the schematic and (very
short) bill of materials:

http://www.sagebrush.com/phontech.htm

Scroll down to the middle of the page.

Good luck!

--
Dmitri Abaimov, RCDD
http://www.cabling-design.com
Cabling Forum, color codes, pinouts and other useful resources for
premises cabling users and pros
http://www.cabling-design.com/homecabling
Residential Cabling Guide
-------------------------------------
[email protected] wrote:

Anyone know how-to make a cable that would plug into my telephone jack
and then into my computer soundcard?

I bought one from EBay and when I plug the cable into my phone line and
then into the soundcard my line
goes dead.

One guy mentioned he uses an isolator circuit of some sort to not short
out the line in his device.

This is the one I bought below that doesn't work.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=14960&item=5774136958&rd=1&ssPageName=WDVW


This one below supposedly works with a soundcard and phoneline.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5769614109&rd=1&sspagename=STRK:MEWA:IT&rd=1


If you can help send an email to [email protected] o m

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[Jim Thompson]

If you are into making things yourself, here is the schematic and (very
short) bill of materials:

http://www.sagebrush.com/phontech.htm

Scroll down to the middle of the page.

Good luck!

Which reminds me. Does anyone have specifications on the
transformer...

RS 273-1374 ??

600-600 doesn't tell you much. It would be nice to know
primary/secondary inductance, and also desirable to know leakage
inductance.

Thanks!

...Jim Thompson

 

[Ross Herbert]

Which reminds me. Does anyone have specifications on the
transformer...

RS 273-1374 ??

That is an obsolete part number Jim. Use either RS 208-822 or 196-959
(latter is my preference).

 

[OBones]

Which reminds me. Does anyone have specifications on the
transformer...

RS 273-1374 ??

600-600 doesn't tell you much. It would be nice to know
primary/secondary inductance, and also desirable to know leakage
inductance.

Oh come on. This 600-600 stuff is STANDARD telephony isolation
transformer. It's got 1:1 ratio, and you don't need to know much about
its inductance, just put it accross the line, with a 200nF 400V
capacitor to filter out the DC part of the telephone signal.
These transformers are readily available, in very small packages, easy
to use.

 

[Jim Thompson]

Oh come on. This 600-600 stuff is STANDARD telephony isolation
transformer. It's got 1:1 ratio, and you don't need to know much about
its inductance, just put it accross the line, with a 200nF 400V
capacitor to filter out the DC part of the telephone signal.
These transformers are readily available, in very small packages, easy
to use.

Oh come on! Some of us like to do special twists and turns to improve
usable bandwidth. I can guess at it, but it's easier when I have
facts.

...Jim Thompson

 

[Jim Thompson]

On Thu, 12 May 2005 18:34:30 -0700, Jim Thompson


That is an obsolete part number Jim. Use either RS 208-822 or 196-959
(latter is my preference).

[snip]

A quick check on the RS site for those part numbers jumps to manuals,
but shows nada :-(

...Jim Thompson

 

[Rich Grise]

Oh come on. This 600-600 stuff is STANDARD telephony isolation
transformer. It's got 1:1 ratio, and you don't need to know much about
its inductance, just put it accross the line, with a 200nF 400V
capacitor to filter out the DC part of the telephone signal.
These transformers are readily available, in very small packages, easy
to use.

Oh come on! Some of us like to do special twists and turns to improve
usable bandwidth. I can guess at it, but it's easier when I have
facts.
[/QUOTE]
You could always get one and measure it. They do still make real
test equipment, don't they? ;-)

Good Luck!
Rich

 

[Ross Herbert]

On Thu, 12 May 2005 18:34:30 -0700, Jim Thompson


That is an obsolete part number Jim. Use either RS 208-822 or 196-959
(latter is my preference).

[snip]

A quick check on the RS site for those part numbers jumps to manuals,
but shows nada :-(

...Jim Thompson

Jim, come now...

Go to http://rswww.com/cgi-bin/bv/home/Home.jsp?cacheID=ukie

and type 196-959 into the entry box on the top left of the page and
hit GO.

Voila! you get a listing of all the 600:600 line isolation
transformers.

 

[Jim Thompson]

On Thu, 12 May 2005 18:34:30 -0700, Jim Thompson

Which reminds me. Does anyone have specifications on the
transformer...

RS 273-1374 ??

That is an obsolete part number Jim. Use either RS 208-822 or 196-959
(latter is my preference).

[snip]

A quick check on the RS site for those part numbers jumps to manuals,
but shows nada :-(

...Jim Thompson

Jim, come now...

Go to http://rswww.com/cgi-bin/bv/home/Home.jsp?cacheID=ukie

and type 196-959 into the entry box on the top left of the page and
hit GO.

Voila! you get a listing of all the 600:600 line isolation
transformers.

The US equivalent has nothing. Did you forget I was on the west side
of the pond ?

...Jim Thompson

 

[Ross Herbert]

On Fri, 13 May 2005 04:36:09 GMT, Ross Herbert

On Thu, 12 May 2005 18:34:30 -0700, Jim Thompson
[snip]

Which reminds me. Does anyone have specifications on the
transformer...

RS 273-1374 ??

That is an obsolete part number Jim. Use either RS 208-822 or 196-959
(latter is my preference).

[snip]

A quick check on the RS site for those part numbers jumps to manuals,
but shows nada :-(

...Jim Thompson

Jim, come now...

Go to http://rswww.com/cgi-bin/bv/home/Home.jsp?cacheID=ukie

and type 196-959 into the entry box on the top left of the page and
hit GO.

Voila! you get a listing of all the 600:600 line isolation
transformers.

The US equivalent has nothing. Did you forget I was on the west side
of the pond ?

...Jim Thompson

Well, I am on the west coast of Australia and I had no difficulty in
locating the product. You obviously know that RS Components is based
in the UK, and because the US representative of RS may not stock all
of the parent company's catalogued products, they can nevertheless get
them in from the UK. If you don't see it on the US website then look
at the parent company's website.

The same thing happens on the RS website in Australia so when I want
an item not shown in the Aus catalogue, but I know it is in the UK
catalog, I ask them to get it in from the UK. After all, most of the
items in any country's catalog are shipped from the parent company, so
its not as if a special shipment has to be made - it just comes in
with the next order. If I had wanted this particular transformer
myself I could have obtained it from the local RS Components branch
since it is also listed under the same part number in the Aus catalog.

You have to think laterally, and not all things are centred around the
US....

 

[John Fields]

Well, I am on the west coast of Australia and I had no difficulty in
locating the product. You obviously know that RS Components is based
in the UK, and because the US representative of RS may not stock all
of the parent company's catalogued products, they can nevertheless get
them in from the UK. If you don't see it on the US website then look
at the parent company's website.

The same thing happens on the RS website in Australia so when I want
an item not shown in the Aus catalogue, but I know it is in the UK
catalog, I ask them to get it in from the UK. After all, most of the
items in any country's catalog are shipped from the parent company, so
its not as if a special shipment has to be made - it just comes in
with the next order. If I had wanted this particular transformer
myself I could have obtained it from the local RS Components branch
since it is also listed under the same part number in the Aus catalog.

You have to think laterally, and not all things are centred around the
US....