[1000mp] Sound card interface to FT-1000MP mic input

[Pete Smith]

Depends.  Every sound card I've dealt with has had a 600 ohm line output, which either drive amplified speakers or could be connected directly to a line level input.  The big thing you need to feed the line output of a typical sound card to an MP mike jack (I do that here) is an isolation transformer and a roughly 10:1 voltage divider to get the level down to what the mike input can handle.

73, Pete N4ZR

At 09:38 AM 9/20/2005, Robert Dorchuck W6VY wrote:
>The sound card speaker output is 8 ohms.  Mic input on the MP is 600
>ohms.  I would use a 8:600 ohm transformer.  I do not think 1:1 would
>be appropriate.  Available at Mouser, etc.
>
>Bob  W6VY
>
>
>--- "A.J.C." <n2ki at amsat.org> wrote:
>
>> Dave,
>> 
>> You can use the 1:1 isolation transformer from Radio Shack.  They are
>> fine.
>> 
>> Tony - N2KI
>> SYSOP - N2KI DX CLUSTER
>> dxc.n2ki.com:7300
>> RF Gateway 145.650
>> Website: www.n2ki.com
>> DX Spoken Here
>> 
>> 
>> > -----Original Message-----
>> > From: 1000mp-bounces at mailman.qth.net [mailto:1000mp-
>> > bounces at mailman.qth.net] On Behalf Of Dave Hawes
>> > Sent: September 20, 2005 05:35
>> > To: 1000mp at mailman.qth.net
>> > Subject: [1000mp] Sound card interface to FT-1000MP mic input
>> > 
>> > Can anyone suggest an appropriate audio isolation transformer to
>> use
>> > between a computer sound card speaker output and the microphone
>> > input
>> > on the MP?  This will be used for contest voice memory keying. 
>> Radio
>> > Shack, Mouser, DigiKey, etc. all would be OK.
>> > 
>> > Thanks in advance.
>> > 
>> > 73 - Dave N3RD