[Elecraft] K3 Hum on Audio...

riese-k3djc at juno.com riese-k3djc at juno.com
Fri Jan 13 16:05:15 EST 2012 

On Fri, 13 Jan 2012 12:26:47 -0800 Phil Hystad <phystad at mac.com> writes:
> bob,
> 
> I am not sure if you understand my previous problems I was 
> reporting.  The hum has nothing to do with the mic plugged into the 
> K3 or not (obvious if the mic is not plugged in, there is no 
> problems).  But, the hum comes with PTT transmit and not merely 
> because the mic is plugged in.  
> 
> But, for some unusual reason, the hum is no longer there.  But I 
> fear it is waiting out there, maybe in the greenbelt behind our 
> house, to make a sneak attack when I least expect it.
> 

Those evil north Koreans
Har

GL on your fixing the problem,,, been there done that

Bob K3DJC





73, phil
> 
> 
> On Jan 13, 2012, at 12:09 PM, riese-k3djc at juno.com wrote:
> 
> > so you unplug the mike input to K3 the hum goes away
> > when you plug into the K3 mike input the hum is there ?
> > I would think you have a bad mike/cord/connecter
> > 
> > Bob K3DJC
> > 
> > On Fri, 13 Jan 2012 11:31:38 -0800 Phil Hystad <phystad at mac.com> 
> writes:
> >> Ron,
> >> 
> >> Well, I just had a quick SSB chat with Clyde (AA7WC) (pre Noon 
> Time 
> >> net on 40 meters) and asked specifically for audio report with 
> >> possible hum.  His report was no hum, clear good sounding audio, 
> 
> >> with S7 signal.
> >> 
> >> So I am suspicious of my florescent lights in the garage although 
> 
> >> they are on right now with no hum.  I am thinking though that 
> maybe 
> >> there is something intermittent with those lights.  But, then 
> again, 
> >> the "something loose in the mic cord" maybe be the cause too.  
> But, 
> >> I jiggled that cord and connection and so on quite vigorously 
> before 
> >> when I had the hum and it did not change the hum status.  Then, 
> when 
> >> the hum disappeared, I did those jiggle the cord and connector on 
> 
> >> the mic tests again and the hum DID NOT come back.
> >> 
> >> Wow, I can't believe I have spent the entire morning fooling 
> around 
> >> with this.  I even called into work and said that I was not 
> coming 
> >> in today just to work on this problem.  I don't really want to go 
> 
> >> outside anyway despite that the temperature has now risen to a 
> >> toasty 36 degrees.
> >> 
> >> 73, phil, K7PEH
> >> 
> >> 
> >> On Jan 13, 2012, at 11:23 AM, Ron D'Eau Claire wrote:
> >> 
> >>> Good luck Phil. That last part really suggests something loose 
> in 
> >> the mike
> >>> cord as I suggested at first. 
> >>> 
> >>> Ron AC7AC
> >>> 
> >>> -----Original Message-----
> >>> Ron,
> >>> 
> >>> OK, now it appears I was mistaken when I said that that the hum 
> 
> >> was in both
> >>> mics.  I think I flubbed something up in my previous test due to 
> 
> >> the way
> >>> that the macros are assigned to keys which led me to thinking 
> that 
> >> the hum
> >>> occurred in both mics.   But, I learned something in this...
> >>> 
> >>> One, don't try to use one of your macro assigned keys (in my 
> case 
> >> M2 and M1)
> >>> while in the menu because that merely reassigns the key to the 
> new 
> >> menu
> >>> entry.  I made this mistake several times this morning.  But, 
> when 
> >> I
> >>> discovered it and then reset my macro definitions, I 
> rediscovered 
> >> that the
> >>> HUM occurs in the front panel MH2 hand held mic only.  I did 
> this 
> >> test
> >>> several times to make sure I was not confusing things.
> >>> 
> >>> I discovered something else that I did not know before.  PTT is 
> 
> >> actuated by
> >>> any of the methods of PTT.  So, when I thought I had the 
> >> headphones CM500
> >>> mic enabled I used my foot switch for push to talk and since 
> that 
> >> worked for
> >>> some dumb reason I was thinking I had successfully switched from 
> 
> >> front panel
> >>> to rear panel.  But, I had not.  I also discovered that I could 
> 
> >> use the hand
> >>> mic (front panel) PTT switch even though my rear panel mic was 
> >> being used.
> >>> Now, after I discovered this, I realize that it is obvious but 
> >> something
> >>> that lead to my confusion.
> >>> 
> >>> So, the problem occurs on the FRONT PANEL mic only and not the 
> >> rear panel.
> >>> And, the problem occurs when the K3 is in TOTAL isolation from 
> all 
> >> AC
> >>> sources except for possibly me.  I mean, I am holding the mic 
> but 
> >> then I
> >>> don't think that is a cause of the hum because I tried it with a 
> 
> >> insulated
> >>> hand and it still caused the hum on the front panel mic.
> >>> 
> >>> I doubt that this is caused by wall-outlet type AC because I 
> have 
> >> erased all
> >>> AC for some of my tests.  And, besides, this problem seemed to 
> >> occur ....
> >>> 
> >>> OK, while writing that last sentence something occurred to me.  
> 
> >> Another
> >>> change I had made on Wednesday after I had my good audio reports 
> 
> >> on the MH2
> >>> front panel mic was that I set the configuration for the band 
> >> specific power
> >>> levels to work with the KPA500.  So, I just now went to test the 
> 
> >> mic and
> >>> change that setting around but the hum is gone.
> >>> 
> >>> I repeat, the hum is gone from the front panel mic.   I now 
> can't 
> >> test the
> >>> band specific power menu setting because I have no problem.
> >>> 
> >>> But, I have a suspicion as to the cause now and I am going to do 
> 
> >> some other
> >>> experiments.
> >>> 
> >>> 73, phil
> >>> 
> >> 
> >> ______________________________________________________________
> >> 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
> >> 
> >> 
> > 
> > ____________________________________________________________
> > Get Free Email with Video Mail & Video Chat!
> > http://www.juno.com/freeemail?refcd=JUTAGOUT1FREM0210
> > ______________________________________________________________
> > 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
> 
> 
> 
____________________________________________________________
Groupon&#8482 Official Site
1 ridiculously huge coupon a day. Get 50-90% off your city&#39;s best!
http://thirdpartyoffers.juno.com/TGL3141/4f109cc1a654273a9m03vuc

More information about the Elecraft mailing list