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Soldered capacitor
The picture on the left, from the 4 State website, shows the method of bending the component leads.
I chose to make the leads longer to avoid any damage from the soldering iron, especially to the transistors.

Antenna coupling capacitor
This is a capacitor added to tune the antenna. It doesn't come with the kit. To couple the antenna to the radio, a very low value capacitor is used. It's made by twisting two pieces of wire together and is called a "gimmick." A gimmick capacitor has a value of about 1 picofarad per inch, depending on how tightly the wire is twisted. I wanted to be able to vary the capacitance.
capacitors in series
The capacitor used was 0 to 28 pF, which is too high. I could only mesh the plates a tiny amount and then it was too much.
I put a 4.7 picofarad capacitor in series with the variable. What do you suppose that did to the value of the variable capacitor?

To calculate the value of two capacitors in series, the formula is C1 x C2 / C1 + C2.
So (28 times 4.7) divided by (28 plus 4.7) = 131.6 divided by 32.7 (I used a calculator) = 4.02. The variable capacitor is now 0 to 4 pF!

It is perfect for this. You don't really need it if you're building the kit; the gimmick will work fine. I just happened to have the variable capacitor available, so I used it.

Gimmick capacitors
Gimmick capacitors. You'll put your eye out with those things!

The audio output of the radio is disappointing. The volume is so low It was actually in competition with the noise from our refrigerator while listening to it. Then I plugged in a pair of headphones and the difference was amazing.

Don't bother trying to improve the sound by swapping the speaker. It did improve the sound, but the two transistor amplifier just can't drive it with very much volume, so the speaker that came with the kit was put back into service.

Once you listen to the radio with headphones you probably won't use the speaker. The volume in the headphones is so loud that you'll have the sound turned almost all the way down.
The speaker frame is very close to the terminals on the regen control, so be careful when attaching it.

2SC458 transistor
two 2SC458 transistors
In another effort to get more volume, I replaced the 2N3019 transistors with some 2SC458s that I had left over from the Astro Commander walkie-talkies (seen elsewhere on this site). I don't think it made a difference. The level of sound from the speaker was still abysmal, and It wrecked the cool look of those silver and brass metal 2N3019s.

The reason I used the 2SC458s was because they worked so well in the walkie talkies. I knew they were good to at least 27 megahertz (way more than what was needed here) and the walkie talkies have plenty of volume.

The "Pittsburg style" construction lets you swap out a transistor in less than a minute. This came in handy when comparing the performance, since listening conditions on the short wave bands can change from minute to minute.
Ocean Hopper
Then it suddenly occurred to me, the 4 State QRP Group considers the "Ocean Hopper" an ancestor of the Ozark Patrol. The Ocean Hopper DIDN'T HAVE A SPEAKER. Instead of trying to improve the dismal volume of the speaker in the Ozark Patrol, just ignore the fact that it even has one.
Ozark Patrol
Perhaps the Ozark Patrol should be made without a speaker. It would be cheaper, and nobody would get the impression the radio doesn't work very well, because it DOES work very well if you use headphones. A cool "4 State QRP Group" decal could be placed where the speaker used to be.

 ...and then I had an idea. 

External Speaker
While watching some YouTube videos of other Ozark Patrols, I got another idea. Yes, another one. That's a total of FIVE, no, THREE ideas! The videos show an external amplified speaker plugged into the headphone jack. So why not make the amplifier INTERNAL or on-board?
LM386 module kit
LM386 circuit board
For a buck you can get this amplifier kit from China on ebay. No postage! I ordered three. I mean, five.
The soldering pads are very small, so there is a learning curve after flowing all that solder onto the Ozark Patrol.
LM386 Amp module
The little amplifier is mounted behind the volume control. "Set it and forget it."

Ozark Patrol
To install the amplifier you first disconnect the speaker. The input to the amplifier is a wire going from the collector of Q2, and another wire going to ground. The leads from the amplifier output then go to the speaker. Power comes from the on / off switch on the front panel. Set the volume on the amp to where you want it, then forget it. You still control the volume from the front panel, but now you have some SERIOUS volume.
See the update below.
You can pick up a ground for the amplifier from any of the screws that mount the speaker. The 9V+ comes from the On/Off switch. The amplifier does not affect the operation of the headphones in any way.

Ozark Schematic
Partial schematic with LM386 amplifier
UPDATE: I had originally connected input of the the amplifier directly to the transformer, which gave the radio a tremendous increase in volume. However, I noticed the sound was a little "scratchy" or distorted, so I wanted to improve it.

By bypassing the last transistor and the transformer, the sound is clearer and the range of the volume control is better. This is very easy to do, all you need is a wire from the collector of transistor Q2 to the amplifier.
Wire on Q2
Here's the wire attached to the collector Q2, which goes to the input of the amplifier.
LM386 amp connection
A wider view.