K3, headphones, and audio limiting??

[callen1155]

Hello folks.

I was operating yesterday with my K2 using headphones.  I really prefer headphones for weak sigs and operating in general but on two occasions yesterday my ears were blasted due to a strong nearby signal. I finally resorted to an external speaker even though can't hear with that nearly as well (I already have greatly impaired hearing).  edit note: I did have the AGC on the K2 set to fast.

So two questions:

1. Does the K3 have an 'audio limiter' that would prevent the above situation and does it work well?


2. This weekend was really my first contest so how does one approach such an event if you operate a rig (such as a K2) where in a flash the volume levels can vary greatly? Do you take the chance and use the headphones? Frankly, I'm very hesitant now to use the headphone with the K2 at any time.

thanks.
chuck
af4xk

[ab2tc]

Hi,

Yes, the K3 has an audio limiter, but more importantly it's AGC can be configured to virtually eliminate audio level differences once the signal is above the AGC threshold. Not everybody likes this, but it will prevent the experience you mention with the K2.

AB2TC - Knut

[Don Wilhelm-4]

Chuck,

The K3 does have an audio limiter whose level can be adjusted - it can
be present when the AGC is off, there is a menu item to control it.

As far as the K2, try operating with AGC on, and the strong signals will
be subdued.  Due to the slope of the K2 AGC response, you can still
determine relative strength of signals with AGC on.  Reducing the IF
passband width (tap the XFIL button) will help keep the AGC from pumping
with the strong signals. (A narrow DSP filter [hold of AFIL button] in
the K2 will not help with AGC pumping because the K2 AGC is in the audio
stages, not at IF as in the K3).

If you did have AGC on with the K2, then you must have had the audio
gain advanced much more than normal, and you mmight want to consider
using a some back-to-back diodes across the headphone jack to serve as a
limiter.

73,
Don W3FPR

callen1155 wrote:

> Hello folks.
>
> I was operating yesterday with my K2 using headphones.  I really prefer
> headphones for weak sigs and operating in general but on two occasions
> yesterday my ears were blasted due to a strong nearby signal. I finally
> resorted to an external speaker even though can't hear with that nearly as
> well (I already have greatly impaired hearing).
>
> So two questions:
>
> 1. Does the K3 have an 'audio limiter' that would prevent the above
> situation and does it work well?
>
>
> 2. This weekend was really my first contest so how does one approach such an
> event if you operate a rig (such as a K2) where in a flash the volume levels
> can vary greatly? Do you take the chance and use the headphones? Frankly,
> I'm very hesitant now to use the headphone with the K2 at any time.
>  
>

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[callen1155]

Thank you Knut and Don.

73
chuck