Sunday, September 17, 2017

First Use of the Emtech ZM-2 Antenna Tuner

HF propagation conditions currently suck, but I wanted to try out the Emtech ZM-2 anyway. My first use would be with a random length antenna.

Earlier today I stopped at Harbor Freight and picked up a one pound spool of aluminum welding wire for ten bucks before the 20% off coupon. We've used such welding wire on our camping trips upstate with good results. In fact, my friend who owns the property we camp on built an 80M dipole with it and strung it about 5 feet off the ground, supporting it with fence insulators. Reception on that antenna is excellent and he's made some contacts as well. It's been there over a year and is still usable.



To support my random wire antenna today I used my 31 foot Jackite kite pole with about 50 feet of the welding wire. I also ran a ground line about 25 to 30 feet and held it down with a big screwdriver as a stake.




The wire was so light that the tip of the mast didn't noticeably droop. The antenna was running approximately East-West, and the ground ran out towards the NE.


Aluminum welding wire is light and easy to work with. As seen with my friend's 80M dipole, it'll last long if its not under much strain. It's cheap enough that if you needed to abandon a random wire antenna made from it, that wouldn't cause concern.

My back patio station today was my 2013 MacBook Pro running FLDIGI and WSJT-X, the ZM-2, Yaesu FT-817ND, and Signalink USB digital interface. I also had a CAT cable for rig control.

I followed the instructions in this video to work the tuner. I found it difficult to see the red LED even though it was overcast, so I need to verify that it's in fact working. Maybe it was luck, but by tuning for maximum noise I really didn't have to tweak anything. When I hit transmit, the rig didn't complain about high SWR.

I briefly tried 40M but had issues getting the antenna to tune on that band. It might be the length of the wire, but again I had issues seeing the LED SWR indicator light up.

As I mentioned, HF propagation is really in the crapper. Before setting up out back, I'd done some work inside using my Icom 7200 and the Ultimax 100 end fed on my roof. The random wire seemed more sensitive, based on the number of PSK31 stations that I saw. However, 20M was mostly dead.

After spotting a number of other stations on 20M PSK31 I closed out FLDIGI and fired up WSJT-X to do some WSPR. On 5 watts, I was in fact getting out.




The screenshot is from WSPR Watch running on my iPhone

This table shows the WSPR stations I received in about 10 minutes of listening.


Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
 2017-09-17 19:28   8P9HA   14.097165   -17   0   GK03fb   0.1   KB3MNK   FN20ic   3378   336 
 2017-09-17 19:28   K7POF   14.097124   -8   0   DM34sr   10   KB3MNK   FN20ic   3312   68 
 2017-09-17 19:28   W6WGF   14.097119   -7   1   EM12rw   5   KB3MNK   FN20ic   2053   61 
 2017-09-17 19:28   VE4WSC   14.097103   -12   3   EN19ku   5   KB3MNK   FN20ic   2019   114 
 2017-09-17 19:26   WA5IWB   14.097094   -14   0   EM10qh   1   KB3MNK   FN20ic   2215   55 
 2017-09-17 19:26   K7RE   14.097146   -10   0   DN84am   1   KB3MNK   FN20ic   2395   92 
 2017-09-17 19:26   K5FRT   14.097012   -21   0   EM10td   0.2   KB3MNK   FN20ic   2206   54 
 2017-09-17 19:24   8P9HA   14.097137   -19   0   GK03fb   0.1   KB3MNK   FN20ic   3378   336 
 2017-09-17 19:24   K6KWI   14.097060   -21   0   DM13cu   20   KB3MNK   FN20ic   3802   67 
 2017-09-17 19:24   N0IJK   14.097052   -19   0   EL19ao   5   KB3MNK   FN20ic   2365   54

I am cautiously optimistic about the Emtech ZM-2 tuner but I need to figure out why I'm not seeing the LED SWR indicator light. My next experiment with it will be with a dipole to be constructed using some 450 Ohm window line that I bought yesterday at Ham Radio Outlet.

Wednesday, September 13, 2017

Emtech ZM-2 Antenna Tuner

Last Saturday I ordered a pre-built Emtech ZM-2 antenna tuner with UHF connectors and it arrived today.  I wanted something a bit smaller and lighter than my LDG YT-100 for use with my Yaesu FT-817ND. Additionally, I wanted a tuner that would work with either coax cable fed antennas, balanced line antennas, or even just a random length wire with a ground.

Unlike the LDG, the Emtech unit is a manual tuner using a Z-match circuit. However, based on several videos I've watched and reviews I've read, it's quick to tune and gives you a wide choice with antennas and feedlines. (See here for a good discussion of Z-match circuits.)

Weather permitting, I am hoping to try it out this coming weekend. In the interim, here's a good video from W2AEW on how to operate the ZM-2.


Sunday, September 10, 2017

NOAA Radio Propagation Dashboard

Currently, HF propagation is terrible, largely due to solar activity. This NOAA Radio Propagation Dashboard helps explain why.

Sunday, August 20, 2017

Kel-Tec RDB Field Stripped

This afternoon I took a few minutes, field stripped the Kel-Tec RDB, and took some pictures. The rifle's design is different enough so that I think you'll find them of interest. Clickenzee to embiggenate.



Slightly closer view of the barrel and bolt groups:



Bolt, bolt face, and extractor. Note the dual ejector plungers on the bolt face.





Piston head. It's a little hard to see but there is a weld blob on the top of the piston. Some earlier rifles left the factory without the weld, which leads to malfunctions.



The gas system.



Bottom of the handguard, showing the molded-in M-1913 rail. I have a Rogers Rail Light mounted.


Disassembly to this stage requires you to push out three takedown pins, plus one pin in the bolt carrier group. If you take down the BCG be careful. The firing pin is spring loaded and if you fail to contain it, it will launch itself several feet. (Yeah, it happened to me the first time I stripped the BCG.)

Scoped the RDB

Yesterday I decided to move a scope I already owned over to the Kel-Tec RDB I bought Friday night. My Colt AR15 6721 has been relegated to backup status and was wearing an IOR Valdada 3x25mm CQB scope.

The IOR scope is built with Schott glass from Germany, has very clear optics, and a nice reticle. The 3x magnification works well from close-up to my club's longest range, 200 yards. It's also built like a brick shithouse, so I am not going to worry about BUIS.



Range report to follow as soon as possible.


Saturday, August 19, 2017

Picked Up a Kel-Tec RDB Rifle

I did some trading last night at Surplus City and came home with a Kel-Tec RDB 5.56mm bullpup rifle. (I actually went there with the intention of ordering an FN PS90. Maybe next time.)  SC was asking $950. I traded in my CZ-52, Bulgarian Makarov, Ruger SP101, Pietta SAA, and Springfield XD-9, none of which I'd fired in years. He gave me $1000 trade in value, so I also got 500 rounds of CCI .22 Short HV to run through my Remington 550-1.





Kel-Tec gives the OAL as 27.3" with its 17.3" barrel. The weight unloaded is 6.7 lbs. The barrel is 1:7" twist. There's a long, T-marked M-1913 Picatinny rail on top but it comes without any sights. I am debating what kind of optic to mount, but it will probably be something along the lines of a 1-4x variable, not just a red dot.


The RDB is a new design, although the bolt itself is very Stoner-ish and it takes AR15 magazines. It came with one 20-round MagPul P-Mag, an owner's manual, and a sling.

There are numerous sling mounting points for the hook-style attachments. In the pic above I had it mounted as a 2-point sling but I later switched it to a single-point using the swivel located in front of the middle takedown pin.

It's a long-stroke, gas piston design. The gas is adjustable to account for variations in ammo or the amount of crud in the gun. However, reviews I've seen state that very little fouling gets into the action. Empties eject out the bottom, through a port behind the magazine well.

The action is very simple and breaks down with only something to drive out the takedown pins. (They may loosen up over time.)

As a southpaw, the best part to me is that it's totally ambidextrous except for the HK MP5-ish charging handle. It can be reversed without tools. All I had to do was field strip the rifle and then put it in the other way when I reassembled. My initial impression of the rifle is that the ergonomics are outstanding.

Because of the long linkage between the trigger and the rest of the firing mechanism, most bullpups have lackluster trigger pulls. Not so in the case of the RDP. It's actually pretty good with some takeup but it's only around 5 pounds.

Between the adjustable gas system, the lack of fouling in the action, and having the ejection port on the bottom of the rifle so gas gets vented downward, it's supposed to be an awesome suppressor host.

In typical Kel-Tec fashion, they are scarce as hen's teeth, though. Kel-Tec announced it a few years ago but they just started shipping in 2016. They are still really hard to find in shops although there are a bunch on Gunbroker.

MAC posted a nice, in-depth review of a pre-production sample on YouTube in 2015:




I should be able to take it out in the next week or two and will post a follow up after I am able to shoot it.

Sunday, August 06, 2017

BBC: Why One Man Left Silicon Valley and Setup a Survival Camp

BBC News published this video, which I think is worth watching. It's only a few minutes long. (I couldn't figure out a way to embed it.) H/T to Tamara on Facebook.

The BBC reporter's reaction to the AR15 was a bit stereotypical, but amusing.

As someone who works in information technology and who is seeing the push to automate more and more, I don't think he's completely off-base.

Heck if I know the solution, though.

Mossberg 500 Super Bantam Shotgun

My 13 year old daughter wants to come hunting with me this year and needed a suitable shotgun. Today, we went to the local Dick's Sporting Goods and picked up this 20 gauge Mossberg 500 Super Bantam for ~$325 + PA's 6% sales tax.


I actually had her try out the Mossberg 510 youth model in .410 bore but she's already outgrown it. That's good because the 20 gauge will throw significantly more shot and 20 gauge slugs are adequate for deer.

Both the stock and forearm are synthetic. The stock is currently setup with a 12" length of pull but it included a spacer to increase it to 13". If she needs a longer LOP it will accept adult-sized stocks. The stock has a good, thick recoil pad on it.

The 22" barrel is threaded for choke tubes. It came with the modified tube in place. Using the included wrench, I swapped that out for improved cylinder. It also comes with a full choke tube. The barrel is topped with a white bead up front and a brass middle bead.

At 5.25 lbs. unloaded it won't be hard for her to carry afield. Heck, that weighs less than her school bag on most days. The stock has a place to attach a sling swivel but the gun didn't come with a stud for the front. So, I found one on eBay and it should hopefully be here by the end of the week. It will thread into an existing hole on the barrel mounting screw. I also ordered an inexpensive sling with swivels and an Outers cleaning kit.

The magazine came plugged so that the only way to load it was singly through the ejection port. The manual states that once your new shooter learns gun safety you can shorten the plug (a dowel) to 9", to allow up to two shells in the magazine. I did so, since my kid is not new to shooting. (Frankly, if they aren't safe to handle a manually operated gun with 3 shells in it, they aren't safe to handle a single shot.)

The unplugged magazine capacity is six 2-3/4" shells. I have some Federal 20 gauge #3 buckshot with which I'll pattern it. It would make a nice home defense shotgun.

Aside from hunting, this will be a good shotgun to introduce my daughter to trap and sporting clays.

Of note, Mossberg has a similar gun in their economy-oriented Maverick line. However, spending more money on the 500 was worth it to us because the Maverick uses a right-handed cross-bolt safety instead of the Mossberg's ambidextrous tang safety. I'm a lefty and my kid is left-eye dominant, and hence shoots portside.

I'll post a follow up after we get the chance to shoot it.

Wednesday, July 05, 2017

More Range Time with the Ruger SR22

My daughter and I hit the range yesterday and brought along "her" Ruger SR22. I put 20 CCI SV rounds through it.  She shot it unsuppressed, so I had her use Remington Golden Bullet high speed brass-plated hollow points.

Golden Bullets don't have a very good reputation for quality but as of a couple years ago Remington seems to have improved them. They run well and give good accuracy in my Remington Nylon 77 and 550-1, so I wanted to see how the Ruger would handle them.

My kid put at least 150 Golden Bullets through the Ruger. We had one failure to go into battery that was resolved by bumping the back of the slide, and one misfire. After trying a second hit, then ejecting the misfire and rotating it 180 degrees, it went off. This isn't unusual with cheap bulk .22 ammo.

I'm happy to see the Ruger function well with the Golden Bullets. They were one of the few types of .22 ammo I was able to lay in a good supply of during the 0bama years.