Dennis,
Impedance matching in audio circuits has not been important since the
days of vacuum tubes with audio output transformers.
Were you operating the KX3 on batteries when you found that oscillation?
If so, the internal resistance of the batteries would be the cause of
the oscillation.
For the computer connection, just use standard stereo audio cables - no
need to match impedance - just set the audio level correctly.
For amplified speakers, I recommend West Mountain Radio COMspkr mainly
because they are shielded and do not howl with the transmit RF.
73,
Don W3FPR
On 6/29/2019 1:01 PM, Dennis via Elecraft wrote:
I searched the KX3 manual and could not find a specification for the
headset/speaker output jack. Last weekend at Field Day I plugged in a low
impedance speaker and got some oscillations above a certain output level.
I want to optimize the impedance match to my computer for FT8 and also know
what speaker impedance would be the best match for my KX3.
Also, what would be the preferred after-market amplified speaker for the KX3?
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]