Send me the amp and the tube and I'll keep them in use for you.  Let me know when you need them back.

Usually not.  For both.

That's not true at all.

A gamma-matched dipole is used to allow grounding of the center of the driven element, which leads to a reactive off-center feed; the gamma match tunes out that reactance and makes  it work the same as a center-fed dipole.

But in all cases, both "halves" of the driven element are equally "hot" and contribute equally to radiation.  It wouldn't matter if a gamma match were "up" or "down."

However, placing a vertically polarized beam in the plane of a conductive mast does detract from performance; nobody in the commercial world would do that.  Vertical beams are always either end-mounted with the supporting mast behind them; or used with a non-conductive support; or stacked side-by-side on opposite sides of a conducting support.

Not sure of the reference there, but "10m" amplifiers are often CB amplifiers pressed into 10m service, and many of those designs are silly, whether they used tubes or transistors...or magic.

I'd be especially careful to avoid "Bi-Linear" amplifiers or those designed to be driven by 4W exciters.  And those which are "RF keyed," requiring no DC keying line...

Right, of course...I was assuming a very high DF, which is what I've found with Y5E/F/P/U/V ceramics and it "sounds" like that's what he has.

AVX rates DF of their Y5 types at 5% to 7.5% measured at 1 kHz, 100mVrms and 25C.  At increased frequencies, voltages and temperatures, they're worse, in my experience.

I use a Boonton capacitance bridge, a variable frequency signal generator (to test at 1 MHz or 10 MHz), an external bias supply and a hair dryer...   Some of the ceramic disc caps I have (other than NP0 and other TC caps) measure very high DFs, way over 25%, sometimes 50%.  I've had some fail, just testing them.

X7R's a lot better, but I don't think that's what he's using based on the description.

If it's a 1000pF capacitor used at 150W output to couple to a 50 Ohm antenna, at that power the capacitor would dissipate about 15W at 28 MHz (Xc = 5.7 Ohms).

That sounds like an accident waiting to happen if the amp really runs 150W and the normal load is 50 Ohms and that's the only output coupling cap to the antenna port.

Is it?

The "superior" part applies to electrolytics...not so much for ceramics.

Ceramic caps in 2013 are made pretty much the way they were made in 1980, when it comes to discoidal designs.

They're still barium titanate, and the electrodes are made or printed about the same way. 

The big difference between "small" and "large" disc capacitors is which material mix is actually used.  Stable dielectrics occupy more space, and unstable ones don't.  But that was true 30-40-50 years ago, also.

Whether that matters is application dependent.

Bandswitch set to 20m, for sure.

LOAD probably needs to be at or very close to "zero" (0).

PLATE should be peaked for maximum output when driven with sufficient power to achieve 200W (probably about 20W drive).

I'd want to know:

Do you intend to use a battery because you want to be "off grid" (so to speak) and not reliant on the AC mains?

Or, will the battery be charged daily, or continuously float charged by the AC mains?

That information is really required to make an informed decision about the battery.

Ditto.  How high is high?

Also, what are you using to measure the SWR?

And also, did you plot SWR vs. frequency across the 440 MHz band?  It's useful to have that data, recorded for reference, so you know how to adjust the antenna if it needs adjusting.

But...ceramic mixes haven't changed all that much over the years.

The "size" of a ceramic cap depends on its design and construction, as well as the dielectric material (ceramic mix) used.  Very high density mixes like Y5P and such can create very "small" capacitors that are very unstable with temperature and applied voltage.  Class I dielectrics like NP0 have much lower dielectric constants and require the capacitors to be larger, but they're also very stable with temperature and voltage.

If the parts are much smaller than the original ones, it "might" be due to technology advances, or it might also be because they're not as good (stable)!

Whether that actually matters is purely application-dependent.

Ditto.  I've seen this effect also.  Seems the algorithms (code) in the controllers aren't always equipped to deal with an already-low SWR.  Just turn the tuner off and use the rig.

I agree for most applications of "long(ish) wire" antennas, wire gauge isn't critical -- as long as it doesn't break, it should be fine.

But for a small loop (like a magnetic loop), wire gauge is very critical and you want it to be BIG because the current is high and conductor losses can be huge.

Two different kinds of antennas.

One thing that's worked pretty well for me as a temporary indoor solution is the MFJ Loop Tuner with as large a loop as I could physically fit in the available space, whatever that was.  I have one of these: http://www.mfjenterprises.com/Product.php?productid=MFJ-936B and when used with a loop made of #10AWG insulated copper wire just tacked up a wall, across the ceiling, down another wall, and back to the tuner -- it makes contacts!  Pretty easily.

Depends on a lot of variables, like what the walls are made of and the structure's exterior siding, etc.  But it's sure better than no antenna, and you can make your loop various ways and shapes to experiment, while using the same tuner.

Note this is not a regular "antenna tuner," most of which are L-matches or T-matches.   This is a special balanced tuner for loops and won't work with a coax-fed antenna.  The loop connects directly to the tuner, without a transmission line.

Send it to this: http://www.thenewstribune.com/

See if they'll pick up the story; it's a bigger paper.

That's a very good deal.

The advantage of such an "iron" is its thermal mass is very large, much larger than the PL-259 connector body you're soldering, so heat transfers from iron to connector very quickly.  These take a long time to heat up, but also a long time to cool down, and that latter feature is a great attribute when you're soldering large items like PL-259 connector bodies.

Using an iron similar to this (I usually use a Weller SP-120), I can touch the iron to the connector body and start flowing solder to the body immediately -- in less than one second.  The job is "finished" about 3-4 seconds later, and the heat source (iron) is removed.  This goes so quickly it doesn't give the soft cable materials chance to reflow and deform.

This is completely inappropriate for delicate circuit board work, or small connector pins; but it's a really good choice for bigger stuff.