What happens if you terminate the cable in a well shielded 50 Ohm termination instead of an open or short-circuit?

You might contact Frank, W2IX.  He's in Carmel and has a tower and HF beam.

K2JO is also in Carmel with a substantial tower and beams.

Sounds like possible shipping damage.  I haven't experienced that, but anything's possible.

At least they're American-based and will cover such stuff under warranty, and from what I've heard, quickly.

Better still, to be assured you don't have such issues, buy a used one from a local ham selling one.   They've sold many, many thousands of these meters over the past two decades and they're always around.

This one is quite good: http://heilsound.com/amateur/products/proset/

I actually prefer a boom microphone and separate headphones, most of the time.  In my case, the reason is a "headset" doesn't allow you a lot of freedom to do things like eat or drink while operating (sometimes a contest necessity); you can push the mike up out of the way, but then you have to pull it back down to use it again.  With a boom mike I can just move back from the mike a few inches, then move in a bit closer to use it, without my hands having to adjust anything.

I'd recommend the Autek WM-1 over the others mentioned.

Autek is an American company with local service and I've owned WM-1s for many years with zero problems.  They work well for their cost point and are very easy to use.

The only other decent "true PEP" HF wattmeter in that price class is the Ameritron WM-30, which uses a cross-needle meter that I don't like as much; but electrically, it works well and about the same as the Autek.  A big advantage of the Autek is that its coupler is remote-able, connected by a cable, so you can hang the coupler where it's convenient for the cables and they don't try to pull the meter off your bench.  You can extend the cable and make it as long as you wish (use shielded cable) -- I made mine about six feet long, and that works fine.

Everything else is considerably more expensive, if you want a PEP instrument that has any sort of local warranty (or non-warranty) service available.

Daiwa doesn't. 

If the gutter downspout and tuner work on HF, they make work "better" on 6m, provided the tuner can find a match.

But stuff is more lossy on VHF.

A good approach might be to install a good mobile 6m antenna on your vehicle, park it outside, and run coax back to the "shack," hidden by bushes or whatever.  Then, if the band really opens up and gets exciting, you may be motivated to take the rig mobile, along with that antenna, find a high spot or a very "open" spot or someplace advantageous for VHF work, and just work it all from the mobile.

You'd have to install a hard-wired method of keying the relay.  The "key" jack is for a code key, not T-R keying.  You could re-wire that jack so it closes the coil connection to the T-R relay, and make that your "amp keying" line.

You'd also have to replace the input and output tank components, which are all set up for 10m (and 11m!) and won't cover 20m at all -- you need "bigger" parts to do that.  And you'd want to re-wire the "VFO" input jack to the cathode tank of the PA tubes so you can use a transmitter to directly drive the PA stage.  The way it's factory wired, if you transmit into the jack labeled "VFO," you're likely to blow up everything that follows that, since it's a low-level input.

What power level do you have it "set" to?

Plan to be at multiop station N6VI, Frazier Peak, CA (DM04) elevation 8012' asl; 6m is 500W to 6L at 55' above ground.

The KX-3 is an amazing piece of equipment but I wouldn't recommend it as a "first HF rig" for anyone.

The digital operation attributes aren't that handy for portable operation, where you still need a keyboard; and popular digital modes are 100% duty cycle modes that will drain the batteries quickly (compared with CW or SSB, which are low duty-cycle modes).  In bright sunlight, I can still work CW or SSB since I don't have to "look" at anything, whereas you may need a shaded area or one protected from direct sunlight to be able to read the screen.

I'd recommend cutting your teeth on something else, used at home; make a lot of contacts, figure out what you really like, and then go for something more appropriate for portable work -- which may indeed be a KX-3!

When you operate some from home, I think you'll find as all of us did that the operator, antenna system and propagation do all the work and the "rig" is pretty far down the list of important stuff.  With a $1000 budget, I'd normally spend $750 on antennas and what's left on station equipment, because that will generally result in the most contacts, the easiest.   Learning operating practices and about HF propagation is important, too, and doesn't cost anything but time.

It makes sense only at higher frequencies.  Obviously 3.9 pF across a 50 Ohm line at 3.5 MHz is doing absolutely nothing.  But as the stripline and its connective wiring becomes less perfect (at higher frequencies) it can require some reactive compensation to try to pull it back to 50 Ohms Zo.  I'd leave them there.

It's odd the problem would occur only on 20m, considering its design; but anyway, sounds like a bad connection at the 20m loading coil, or the "L20" tuning spokes (4 of them), or the coil strap at the 20m coil connection.

I'd take it down, carefully inspect, make sure all connections (hardware) is very tight, including the tubing clamps.  I hope you used an anti-oxide compound like NoAlOx or similar during assembly, otherwise intermittencies can occur where the tubing sections join and you can't visually see that.

I built a DX-60A back in the mid-60s and used it on AM a fair amount for a while; the D-104 seems a good choice (it's what I used, also) because it has a light of "brightness" to it (high frequency response), and the DX-60 unmodified is a little bit "dull" sounding (too many lows) -- the D-104 "brightens it up" a bit and sounds pretty good.

Of course, there are modifications that can be made to almost anything including the DX-60 to make it sound a bit better than "stock."

Why not try the D-104 and see how it works?  The AM guys who are rabid AM enthusiasts (quite a lot of them!) are all into "modulation," and will give you some critical reports.

I've been active on VHF weak signal modes for about 45 years and surely agree that when the 6m band is "open," a lot can be done with very little.

However, for the other 95% of the time when the band is not open, small antennas -- especially vertical ones -- typically yield a lot of "nothing heard here."

An interesting and somewhat eye-opening test which I've demonstrated hundreds of times is this one I run at home:

6m loop at 30 feet; Cushcraft Ringo vertical antenna at 30 feet; 7 element horizontally polarized beam on telescoping tower whose height I can change from about 28 feet to 65 feet by telescoping or nesting the tower.  All low-loss feedlines brought to a 4-position antenna switch, so antenna changes can be made in less than a second.

Tune around with the beam at 65 feet, and with various beam headings, I can hear six 6m beacons 24 hours a day, regardless of propagation.  (When the band's open, of course, there are many more in various directions depending on conditions at the moment.)  But those six vary in distance from about 60 miles to about 300 miles, and they're always readable.

Now, switch to the loop:  Two beacons can be heard, weakly, not nearly as well as with the beam.

Now, switch to the vertical:  One beacon can be heard, very weakly.

Works this way every single day.

The antennas all "work," but the beam's advantage is so obvious that many are astounded.

So, on an average day with no special conditions (no sporadic-E, no any kind of ionospheric propagation), just tropo, I can "work" stations in about a 300 mile radius (about 283,000 square mile area).  On the same average day, I can "work" stations in about a 60 mile radius using the loop (about 11,000 square mile area).  The difference in the number of stations that might be workable is a ratio of 283/11, or nearly 26 to one, in favor of the beam.

That's why if 6m is "pretty quiet" using the beam, it can sound "abolustely dead" with a loop.

 

I think whoever told you that didn't know much about antennas or propagation.  Half the HF ham radio world uses vertical polarization, and it's predominant on the lower bands, especially 80m and 160m, where verticals are used extensively for transmitting.  The statement you quote begins to "sort of" apply to cross-polarization for direct-wave or tropospheric paths, as we mostly use on VHF and UHF (and SHF, and EHF, etc).  But almost all our HF work is ionospheric; the signal is refracted by the ionosphere and returns with different polarization, largely circular, and changing.