Steve,
With audio, you can forget about matching impedance, it is the voltage
that matters. An audio amplifier will operate into a 4 ohm or a 1000
ohm load just fine. With the 4 ohm load, power is required, but for a
1000 ohm load, not much power is necessary.
But more direct to your question, the K3 or K3S does *not* need
amplified speakers, but for the KX3 you will likely want amplified
speakers for adequate volume in the home hamshack application - the
audio amplifier in the KX3 is designed for low receive current draw and
that means it does not have powerful audio, but is entirely sufficient
for headphones or the efficient internal speaker.
There is no harm in using amplified speakers on the K3 (K3S) but it has
enough audio power to use non-amplified speakers.
Yes, ordinary computer speakers are subject to RF pickup resulting in
'howls' and other noises during transmission, thus my recommendation to
use shielded speakers (if they are amplified) in the hamshack.
The COMspkr is a communications quality speaker, and is great for normal
ham use. If you want full range audio for HiFi SWLing, use something else.
73,
Don W3FPR
On 11/22/2015 4:15 PM, Steve Ellington wrote:
Am I missing something? Why would one want to use an amplified speaker on a
K3 since the radio already has an amplifier? Doing so would seem to invite
distortion and RF pickup. The K3's audio output is supposed to have a 4 ohm
load and computer speakers are probably closer to 1000 ohms. It's almost
like having no load at all. I don't think that's good for the K3's output
chip.
I have the West Mtn. speakers here and they sound rather poor compared to
almost any comparable computer speaker.
______________________________________________________________
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]
