Audio issues tracked down?

More audio issues?

This morning, I checked into the MIDCARS net on 7.258, at around 9:30 AM.  The reply I got from the service control operator at the time, George K8HLJ, was that my audio was quite distorted.

What?  On 40 meters?  I had not had such a report on that band before.

Another guy chimed it to say it sounded like I perhaps had RF coming back into the radio; maybe I didn't have a good enough match to the antenna, or maybe I had a ground problem.

I turned down the Mic gain a bit (I noticed while talking that I was overdriving it a bit).  George said that it did get better, but was still somewhat distorted.

I was a little disheartened.  But, I tuned aside a bit, tossed out a carrier, and checked my meter.  Sure enough, although I had tuned 7.258 to a 1:1 match the night before, I was now at about a 1.2:1 SWR.  It seemed that I couldn't get quite a good match at my "normal" antenna tuner setting (capacitors at about 2, and the inductor on H).

So, I consulted the manual for the tuner.  It said that if you're unable to get a match, turn the inductor down one letter and try again.  So, I turned the inductor down to G and the capacitors up to about 6.  I was still not able to get a really good match.

So, down once more for the inductor, down to F.  I had never tried tuning 40 meters with the inductor on F.  But, with the capacitors at about 8, I got a perfect match.  Hey!  Here is picture of the rig putting out over 130 watts on 7.258 with practically zero reflected power:

(Note: the tuner manual does say "Always use the lowest alphabetical setting possible."   Also, the manual suggests both 6/G/6 and 8/F/8 as potential matches for 40 meters.)

In the early afternoon, I checked in to the net again and asked for an audio report.  This time, I was met with glowing audio reports from Jim KT4FQ as well as one other perosn.

I said "Well, the main thing seems that I need to get better grounding in my shack.  Which means that I need to get some grounding in my shack."  I was met with laughs of agreement.

When I posted a similar story on Facebook, my friend Jeff (W0ODS) also agreed that the grounding is important.  Currently, I have none at all.  I need to route my cables into my house a little better (currently they come in through open windows) and I need to ground the shields at that point and run a ground wire around to the service entrance ground.  Then I need a ground bus on the desk so that I can also ground all my equipment.  Also, I'm planning on wiring up the TS-520 for DC power (I have an Astron 35amp power supply sitting mostly unused) and also providing DC to light up the lamp on the tuner meter.

Working QSX

In my previous blog post, I mentioned trying to "work split" with a station that was "listening up 5".  Well, today, I found one again.  This time, it was C6ADX calling CQ from the Bahamas.  He was transmitting on 21.285 and listening on 21.290.  I tuned about 10KHz away from him to tune up my transmitter and antenna, ensuring I had as good of a match as I could get.  I tuned back to him and practiced my "RIT button / knob twist" technique for a couple minutes to hear the calls and replies, and then tried calling him.  This meant that I needed to turn the knob 2KHz to the right, key up the mic and talk, and then turn the knob 2KHz to the left so I could hear his reply.

On the fourth try, he heard me.  He gave me a 59 signal report; I gave him a 58 in return.

I tried making a few other contacts on 10 and 15 and 20 meters, but to no avail.  That's OK - I think I ran my audio problem to ground, so to speak.

Hopefully soon I'll actually get a "shack" picture and an "antenna farm" picture posted.

73 de Mike K9MJA