[Elecraft] K3 P3 Spurious signals

[Peter Lambert]

Hello Fred,

I see a very similar thing on my IC-7700.  Different frequency spacings but
pretty much as you described.

They're visible on the band scope but that's it.  I can't detect any I'll
effect from them.  They're so far down to be of no consequence.  I write
them off as images in the DSP processing that produces the bandscope and
appreciate that absolutely nothing is perfect.

73's Peter VK4JD

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Fred Jensen
Sent: Tuesday, 19 February 2013 6:42 AM
To: Elecraft Reflector
Subject: [Elecraft] K3 P3 Spurious signals

K3 [#642] w/P3 in FixTune mode [cursor moves, ends of screen are fixed]. 
  K3 has the resistor mod to increase the 8 MHz IF output.  I see them on
CW, I haven't tried SSB.

I've got a pair of weak, steady spurious signals ~14.5 KHz above and below
the VFO A cursor.  They tune with the VFO [i.e. I can never tune to them]
With a noise floor around -135dBm, they run about -115 dBm.  I see them only
on 10m, however my noise floor is in the -120 to -115dBm range on other
bands and they may be there and I just can't see them.

With no antenna, the signals appear to be each bracketed by two very weak
bands of noise about 2 KHz wide, about 3 KHz above and below each signal.
They only show up on the waterfall [I use a monochrome WF].

The K3 and P3 appear to be working just fine and I only notice them because
when I tune VFO A, I end up with faint slanting traces on the WF.  Anyone
have an explanation?

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2013 Cal QSO Party 5-6 Oct 2013
- www.cqp.org

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html