[Elecraft] Re: K3 Firmware Rev. 2.76: No AF noise burst; PRE/ATTN independent for sub RX; etc.

[wayne burdick]

Christopher Kovacs wrote:

> I too still suffer from the notorious "pop" when powering on.  I would 
> be interested if this change may help.

The "AF noise burst" that is eliminated by the latest firmware was 
caused by the AGC being turned off until about 2 seconds after 
power-up. If you had been tuned to a strong station, with the old 
firmware, you could hear a couple of seconds of very loud audio. That 
no longer happens.

The "pop" heard in the speaker when turning on is an inherent property 
of the speaker amplifier IC, and cannot be changed in firmware. If we 
come up with a way to minimize this, we'll let you know. Meanwhile, you 
could plug in your headphones just when turning on power; this cuts off 
the speaker amp.

73,
Wayne
N6KR

---

http://www.elecraft.com