That sinking feeling

Oy!

You know that sinking feeling you get when you step into the shack and you turn eveything on and something isn't right? And the last time you were in there, everything was working perfectly?

That happened to me yesterday. I stepped into the shack, turned everything on and the KXPA100 sat there like a silent, dark brick. Normally, when I turn on the KX3, the LEDs on the KXPA100 come on, even though I keep the output at 5 Watts. I like to know it's available when I need it for checking into the St.Max 80 Meter SSB Net on Sunday evenings, or for a possible DX ATNO popping up on the bands.

That didn't happen yesterday. It just sat there, foreboding and lifeless. 

The first thing you have to do is choke back that feeling of panic. Really ...... no one in their right minds wants to take a piece of hardware off line and deal with getting it repaired. In a perfect world, that never happens - but as we all know, this world ain't perfect.

So the next thing you do is start the troubleshooting process. And oddly enough, that begins with turning the KXPA100 "on". Weird, right?  But not really.  In use, the KXPA100 power switch is to remain in the "off" position. The KX3 itself is supposed to turn the amp on during power up.

Thankfully, when I flipped the switch on, all the LEDs lit and I heard a few relays click, so that meant the amp itself was okay. So that leads us to figure out why things still aren't right. Everything was fine when I last left the shack - what changed? What would cause the KX3 to stop talking to the KXPA100?

As it turned out, I finally remembered that during my last time in the shack, I had pulled the radio a little closer to me on the operating bench. Something must have happened then. I looked at the left side of the radio, where all the cabling is and I noticed that one cable appeared not to be pressed in all the way. And it took a real close look, because we're talking just a couple of millimeters here. Not even noticeable unless you were specifically looking for it. I gave the plug a push and, lo and behold, the lights on the amp came back on and everything was back to normal! Crisis averted! 

When I pulled the radio forward, I must have inadvertantly tugged on that cable, causing the problem. While I could very easily live without the KXPA100, I have become accustomed to, and enjoy checking into the St. Max Net on Sunday evenings, and as much as a dedicated QRPer as I am, I also have enough common sense to know that the KX3's maximum 15 Watts just will not cut it for effective communication there.

Oh well, what the heck are a few more gray hairs?

72 de Larry W2LJ

QRP - When you care to send the very least! 

Productive day

I had a good day yesterday. After I finished the grocery shopping and yardwork, I was able to grab a short catnap before my weekly Skype session with Bob W3BBO.

Afterward, I went down into the shack and installed one of those new S40A1 diodes that I had ordered for my Astron RS-35A. After soldering the wire back on and installing a new fuse, I crossed my fingers and hit the switch. The fuse didn't blow, I heard that satisfying hysteresis hum and measured 13.65 Volts at the output terminals. Huzzah!

That inspired me to put the KXPA100 back in line. Surprisingly, I remembered how all the cable connections went and everything seemed to work fine - for a few moments. And then came some agita.

When I would try and tune up on 20 Meters, I would get an "ANT FLT" - antenna fault error on the KX3 display. The receive went dead - everything remained on, but I couldn't hear anything on 20 Meters. I checked the other bands and they were fine. I went back to 20 Meters, took the PA offline and everything was perfect! 

What the heck?

It turned out that when I would switch the KX3 over to 20 Meters, for some reason unbeknownst to me, and perhaps only to God, the KXPA100 would switch from ANT1 to ANT2.  I only use the ANT 1 input and I switch between the Butternut HF9V and my W3EDP using an antenna switch. This makes it easier to disconnect antennas before a thunderstorm. I only have to disconnect the coax going from the antenna switch to the back of the KXPA100 instead of disconnecting two antennas from the back of the amp. It was a simple matter of hitting a button on the front of the KXPA100 to make sure I was on the ANT1 input. From there, I switched to the other bands, and then back to 20 Meters to make sure the amp stayed on ANT1 and did not change over to ANT2. Success and a sigh of relief!

The beauty of the KXPA100 is that it allows me to stay at 5 Watts all the time. ONLY when I increase power output above 10 Watts does it kick in and go to work. However, it has the same internal ATU as the KX3 and as long as it is powered on, the KX3 will use the KXPA100 ATU no matter what the power.

That done, I worked four POTA stations, including EC1R in Spain on 20 Meters. I tried calling him with 5 Watts several times with no answer. I then dialed the output up to 50 Watts and was answered, first call. I got a 559 report and I gave him a 579 report.

It's comforting to know everything works. 

72 de Larry W2LJ

QRP - When you care to send the very least!

 

Going back to basics - and purer QRP operating.

 I noticed something Friday night during the Zombie Shuffle.

I decided to unhook the HF9V from the KXPA100 and connect it directly to the KX3. After all, it was a QRP event and anything over 5 Watts wasn't kosher - so what did I need the amp for? Signals were noticeably louder and again, there was noticeably less background  noise on 40 Meters. This, even though the KXPA100 was being totally bypassed.

I am not getting rid of the KXPA100 by any stretch of the imagination - so any of you who might be out there and are hot for one - don't start salivating. But I am going to take it out of line for the time being and will use it only if I need to work an ATNO DX entity or a special Special Event Station - where QRP just doesn't seem to be getting through. I mean, that's the only reason I got it, anyway. It's easy enough to put back in line in less than a minute, if need be. Just move both the computer cable back and antenna connections back to the amp - that's it ..... easy peasy.

Moving the USB cable from the back of the KXPA100 directly to the KX3, allows my logging program to still recognizes what frequency I am on.  Isn't that something? I guess I've gotten so lazy that I prefer the radio telling the computer what band and frequency I'm on rather than typing it in! LOL! And I remember the days when there was ONLY paper logging. How spoiled I've become!

I plan to purchase a DAIWA antenna switch so that I can still choose between the HF9V and the W3EDP (whenever I get THAT back up). I have an MFJ switch ..... but it leaves a lot to be desired. Strangely, it's the only MFJ product I've ever purchased that I was not satisfied with, 

Unfortunately, ANT1 and ANT2 function on the KX3 doesn't work without the amp, but that's a convenience I can learn to live without. I guess the extra relays and antenna jumper connections do make a difference, especially when you're dealing with receiving less than 20 over 9 signals. The purer the connection, the better.

72 de Larry W2LJ

QRP  - When you care to send the very least!