Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: CWget input to my laptop?  (Read 6082 times)
KE4JOY
Member

Posts: 1377




Ignore
« on: July 18, 2013, 05:30:11 PM »

Saw a thread that mentioned CWget software. I downloaded the trial and now I'm fascinated. I got it to work by laying my headphones over the microphone 'hole' on my laptop but that's a tad impractical. The program mentions connecting directly to the audio input. The only audio input this laptop has is a microphone jack. I'm a little Leary about connecting an 8 ohm audio output from a receiver into a microphone jack in my laptop.

I sure don't want to screw up this laptop  Grin

any advice?
Logged
W5UXH
Member

Posts: 20




Ignore
« Reply #1 on: July 19, 2013, 05:30:39 AM »

Have  you considered a USB sound card that has LINE_INPUT?

Logged
K8AXW
Member

Posts: 3836




Ignore
« Reply #2 on: July 19, 2013, 08:55:30 AM »

The best insurance for this potential problem is an interface with adjustable level controls.
Logged
STAYVERTICAL
Member

Posts: 864




Ignore
« Reply #3 on: July 19, 2013, 10:26:53 PM »

Use a little audio transformer, like used to be sold at radio shack.
Or you could use the ones which are sold for use with car stereo systems to avoid ground loops.
Basically don't allow a physical connection between your laptop and the radio, as if you have a difference in voltage it will result
in a current, and that may not be too good.

An audio transformer will completely isolate the input and output and give you peace of mind, while avoiding ground loops.
If you want to get fancy, put a potentiometer of around 1K ohms across the audio transformer output and put the wiper (centre)
to the microphone input.
Remember, use only the tip of the 3.5mm stereo plug that you use for the microphone input as some microphone inputs have
a low voltage on the ring to make an electret microphone work.

Another option is to buy an interface like a Tigertronics USB signalink, which will just plug into the usb port on the notebook,
and completely isolate the radio.
But for an input only it seems like a bit of overkill, so just get one of those little audio transformers, put a 1K ohm resistor in series
with the output to not short any voltages on the microphone input and feed the other set of windings with the 8 ohm speaker output.
Use a multimeter to make sure there is not DC connectivity between the input and output windings just to be sure.

Another option is to get a small cheap pc microphone, and a small speaker, put them both in a tube - tape them together and you are done.
You have just made yourself an old style acoustic coupler which will isolate the input and output.

I know it seems like a lot of paranoia but you seem to be very wary of causing any damage, so that is why I am suggesting
you double check things.

Hope this helps,
73 - Rob
« Last Edit: July 19, 2013, 10:30:33 PM by STAYVERTICAL » Logged
VA7CPC
Member

Posts: 2386




Ignore
« Reply #4 on: July 20, 2013, 08:16:46 PM »

+1 for the USB soundcard.

They're small, cheap (some of them), and (in my experience) work quite well.   QST did some testing a few years back, and found no difference (for ham work) between "cheap" and "expensive" soundcards.

.                 Charles


Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!