ARRL SSB 2018 Contest Results

The remodeled station performed well today during the ARRL SSB 2018 Contest. The station got a thorough high power workout today on 15, 20, and 40 meters. The results were very exciting to say the least!

There were a few tuner training issues, but the AT-AUTO’s caught up on the fly, after that, it was smooth sailing everywhere I went. As usual, I was able to work everyone I could hear. In spite of my compromise 40m antenna, I was able to work all the Hawaiian contesters along with KL7RA on 40.

The only glitch was the HF rotor azimuth indicator stopped working! Of all times for a rotor to fail! Actually the rotor still turns AOK, but the control box no longer indicates its position. If I’m really lucky, I’ll find pin 2 is not making contact at the back of the controller. Worst case: the position potentiometer in the rotor will have to be repaired or replaced. Not a big deal for now. The rotor in question has been in service for 14 years. So I worked this ARRL SSB 2018 Contest with the antenna fixed at 90 degrees.

ARRL SSB 2018 Contest Battle Station!
Contest Battle Station!

Objective: To encourage W/VE stations to expand knowledge of DX propagation on the HF and MF bands, improve operating skills, and improve station capability by creating a competition in which DX stations may only contact W/VE stations.

W/VE amateurs: Work as many DX stations in as many DXCC entities as possible on the 160, 80, 40, 20, 15, and 10 meter bands.

DX stations: Work as many W/VE stations in as many of the 48 contiguous states and provinces as possible.

Have you been here yet? Click through the link to learn more about the contest station.

ARRL DX SSB Results – 030418

The ARRL DX SSB Contest went great! Everything performed well, as expected.

Once again, I was able to work every station I heard. Using a Flex 6300, I worked S&P while utilizing a “3 click” zoom level which makes finding the ‘little pistols’ much easier. I then proceeded to rake the bands for all the tiny, in-between signals I could find, resulting in some great contacts. We’re talking about DX contacts at the RX noise level, in between two stations, (often ‘big guns’) blasting away. Very challenging play today! Very impressive TRX performance from the 6300. I can only imagine what an upgrade to a 6700 will be like. For this contest I used a 4K monitor for the first time. The added resolution made finding the ‘tiny’ guys that much easier.

What makes working the ‘tiny’ signals possible is the Flex ability (no pun intended) to place a custom width passband anywhere you need it. In this case, I place a 1.3khz passband in between the opposing stations. This allows me to pull the DX right out at the RX noise floor. The passband filter is sharp enough to sufficiently isolate these minute signals and render them listenable. Amazing. Next time, I’ll capture video. I made great contacts this way throughout the contest. Of course I work all the big guns as well, working them early (6am Local) and then hearing them in pile-ups later on!

By the end of the contest I found it difficult to find anyone that I had not already worked! After adding a 6700, the only other REAL improvement I could make would be the addition of a tower and full size antenna. Since I can work everybody I can hear, it only makes sense that I acquire “bigger ears”.

Audio Mixer: Samson SM10

I need a 1U mixer to combine the audio outputs from three PC’s and three radios. At this point it looks like the obvious choice is the Samson SM10.  With 8 stereo, plus 2 mono line inputs this mixer fits the bill perfectly.

The Flex 5000 has a balanced line input, as does the Flex 6700, so  I’ll run a balanced line to each radio. This will allow audio from the PC’s and/or radios to be played back over the air. The effects send will be used to supply audio to the input of the Dark Ice Live Audio Streamer (running on the Ubuntu server). Web users will be able to stream live audio from any device in the shack that I choose.

The PRO-2500 Power Strip has to move to make room for the SM10 mixer

I will move the Monster Power PRO 2500 to the rear rack rails, and use that space for the SM10 mixer. I need to have the mixer in that rack position more than I do the two electrical outlets. This should be the last move before the new equipment is added and the station is finally complete. (XYL laughing in the background)

Back To The Front

I’ve Decided, It’s a FlexRadio 6700…

After careful consideration I’ve decided to purchase the FlexRadio 6700.

It came down to several things:

  • RX comparison between Flexradio 6600/6700 nearly identical
  • 6700 only 3.5″ in height
  • 8 panadapters vs. 4 on the 6600
  • Contest BPF not enough reason for a 6600
  • 6600 mic connector on rear

I’m convinced the receivers in both radios “are close enough for jazz”, in that the RX specs are virtually identical. The 3.5″ height means I can remove this shelf and fit the 6300,  6700, and an  LP-500.

FlexRadio 6700 will reside here...
I’ll remove this shelf to make room for the 6700 and the new LP-500 Station Monitor

Comparisons also show that the 6700 is better suited for satellite work, should I ever decide to move SAT operation off the Flex 5000. Investing in a 6600 also meant the LP-500 would not fit. I was able to engineer a clamp-on shelf for the LP-500, but I would much rather have it in the rack.

I noticed the Flex website has announced that the 6600’s are shipping. This may cause a drop in the price of the FlexRadio 6700. We’ll just have to see how it goes.

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Rotors Make The World Go Round…

My 14 year old Yaesu G-800DXA rotor has malfunctioned for the first time. It can be turned using the left/right switch, but there’s no movement of the azimuth indicator. This could be as simple as a bad connection, caused when I pulled the connector from the controller during the remodel. It’s possible, as I remember having trouble getting the connector out.

It could also be that the position potentiometer inside the rotor has failed. In which case I now have a “Plan B”. If the problem turns out to be inside the rotor I’ll replace the rotor, and consider repairing the old one for some future use.

I also have some rough spots in the G-800SDX rotor that I use for SAT azimuth. The rotor gives bad indication between 100 and 160 or so. This is surely an indication of impending failure. No worries, as the rotor was acquired secondhand for peanuts, and has been in operation for 6 years. It still works and will stay in operation until I replace the the HF rotor. The plan is to buy another G-800DXA for the HF antenna (since I already have a working computer interface card for it). FWIW the Idiom Press RotorCard from is highly recommended. It gives your rotor its own COM port number, and can be accessed by any software.

If possible I’ll change out the SAT and HF rotors the same day. I will most likely purchase both rotors (G-5500 and G-800DXA) new from wherever I find the lowest price. I’ve owned the Yaesu G-5500 AZ/EL Rotor, and there’s no doubt it’s the best. My cobbled together KENPRO/YAESU combo has been serving me well, it enabled me to get back on the satellites at a greatly reduced cost, and was a deciding factor to stay on with the SATS.

The existing satellite rotors will be replaced with a Yaesu G-5500 AZ/EL

Yaesu G-5500 AZ/EL from my previous installation.

I’ll use the leftover G-800SDX to turn the W6LVP Loop. We all know a rotor for the RX only Loop Antenna is a must have. The loop can be rotated to find the null or the peak, depending on the signal situation. Thus far I’ve only used the loop in a fixed position, so utilizing a rotor will open up some new possibilities.

For the replacement rotor I am considering the Green Heron G800/RT21 system. I’m waiting for a reply on the shipping cost before I order.

UPDATE: 030818 – Well, I got my answer from GHE. I’ll be shopping elsewhere…

TelePost LP-500 Digital Station Monitor!

The next new addition to the station will be the TelePost LP-500 Digital Station Monitor. A must have to ensure proper station operation.

TelePost LP-500 Digital Station Monitor
The next addition to the station

From the TelePost LP-500 Website:

What is LP-500?

The TelePost LP-500 is a digital station monitor which displays detailed information about the transmitted signal of a station.

It displays the sampled signals in numerous formats including:

  • Power/SWR
  • Oscilloscope type display
  • Spectrum display

The sampled signals are obtained by demodulating the RF,  like in a traditional wattmeter, and should therefore work on any frequency for which there is a suitable directional coupler with the appropriate voltage scaling and time constants.

It should be noted that demodulated samples are audio frequency based and not the same as RF samples. With some types of modulation, the demodulated audio is not a linear representation of the modulation signals, therefore the spectrum display works quite differently than a true spectrum analyzer. This doesn’t pose a problem for AM signals, where the demodulated audio is faithful to the modulation signal, but is a challenge for SSB and other signals without a carrier. For this reason, we have developed special test signals which allow for some traditional SSB tests to be performed, although the tests cannot be directly compared to measurements from a true spectrum analyzer.

In many cases, though, similar information can be gleaned from the tests, and they can be used for comparative tests to see the effect of changes to the transmitting equipment. 


TelePost LP-500 rear panel
Business end of the LP-500

When you're linear, it shows!
So you know you’re perfectly linear!

To utilize this feature two couplers are required (per radio in my case). I plan to have both the 6300 and 6700 using input and output couplers configured like this:

TelePost LP-500 wiring diagram
Block diagram of LP-500 hook up

I’m looking forward to installing the TelePost LP-500 as soon as possible. There’s a waiting list, and I had to pass on my position in the list due to an unforeseen expense at the time of availability.

I can see on the TelePost website that regular shipping is back in full swing.

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Handie Talkies

My first transceiver was a Realistic/Radio Shack HTX-202 “handie talkie”. They can be seen in pictures of my shack from the 1990’s. I used HTX-202’s and 404’s for packet radio when I first got started. They sure took a beating! I ran them 24/7 for 10 years. They were relatively inexpensive, and they worked great for packet. I eventually replaced them with Kenwood TM-V7A‘s.

The HTX-202’s worked great for packet radio!

The Kenwood’s were dual band transceivers and I connected a TNC to each side of the radio. I could do packet radio V/U V/V U/U. It worked so well I bought two of them. They also did 9600 baud which was a deciding factor.

Six packet radio ports on the air @KB2SHU in Cerritos CA

I never experienced any problems with the TM-V7A’s either. I had started as an SWL with a Kenwood R-5000 and after success with the TM-V7A’s I decided to look at the Kenwood HT’s.

Being a digital enthusiast, I purchased the Kenwood TH-D7A handie talkie because it had a TNC and APRS built-in. It was another good investment, and I kept it for several years. I currently own a Kenwood TH-F6A. It’s very small. I bought it because I could carry it in a shirt pocket.

Then, there is the argument for the Baofeng . The Baofeng UV-5R has taken the amateur radio market by storm. These inexpensive $25 HT’s get the job done. Nothing fancy for $25, but they will get you into the local repeaters and sound just as good as anything else. I hear people using them all the time. And it never fails, someone will say “Hey, you sound good,  what are you using?”. Hard to tell what it is by the sound….could be a Kenwood…or a Baofeng!

Great little No Frills transceiver!

It’s amazing these can be sold so inexpensively. In the beginning it was hard to believe the price. Quite frankly, I didn’t care what it sounded like for $25, as long as it worked! I have no problems working the local machines with my UV-5R. Is it a Kenwood? No, of course not. But it’s $25! Buy two! Give them as holiday gifts! Keep one in the car, just in case!

No, I have no stats on failure rates. Like all my comments, these are based on my personal experience only. As they say: “Your mileage may vary”

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SEO Breakthrough

It seemed like I wasn’t getting anywhere with the first SEO (Search Engine Optimization) plugin I installed. Today I installed Yoast SEO and I could immediately see what was lacking in my SEO configuration. You could say I had an SEO Breakthrough!

100% Local SEO
Homebrew SEO

Yoast is light years ahead of their competition. I found their user interface genuinely intuitive. Interpretation of the Yoast interface  guided me to making the following improvements:

  • Added ‘tags’ to all posts
  • Added ‘focus keywords’ to all posts and pages
  • Fine tuned content for improved SEO ratings
  • Search Result ‘Appearance’ settings
  • Keyword Research

I spent approximately 3 hours inputting all the new SEO data. It was not difficult, just time consuming, since all my pages and posts required the updates. Of course, now that I know what each post and page requires in order to meet Yoast SEO standards, I will include that SEO data as I create new content. e.g. this post.

There has been significant progress made in driving traffic to the site. Before I installed WordPress my legacy website averaged 400 visits per month.

Since installing WordPress (and the limited SEO plugin I just replaced) on 12/10/17, web traffic has increased from the average 400 visits to (whats tracking to be) 4000 visits this month. Here is my AWStats data for the past 12 months. Go ahead and click, you can look through them if you like.

I’m finding Bing to be far more responsive than Google. I noticed that some subtle changes in “appearance” I had made, showed up quickly in Bing results, while not showing up at all on Google. Also the Google Search Console is virtually empty, while the Bing console is reporting everything. I’ve entered my “Google Verification Code” into Yoast, and I’m hoping this helps improve the results with Google. I’m certain both services crawls are allowed. Bing seems to be the “first to the party”.

The Bing Webmaster “Diagnostics and Tools” section includes a “Keyword Research” function. I used this tool to determine the most used search terms (keywords) as they relate to amateur radio, and more specifically, my website.

I’m hoping it will improve search results now that I’ve incorporated all the top rated keywords I found, into my content. I have no idea if this will improve placement in search results. However, it should cause my site to appear in search results it would not have appeared in prior to today’s enhancements.

It will certainly be interesting to see what affect, if any, the changes made today have on traffic and search results.

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The Compromise Dipole

A better title might have been: “The Compromised Dipole”.

Due to the limitations of the small residential lot I live on, I am no longer able to get anywhere near the proper height for my 130 foot dipole antenna. At the present time the ‘apex’ is a mere 6 feet or so above the roof line. This is why I refer to it as my “Compromise Dipole”.

There was a time I had it 50 feet above the roof line. Truth be told, I never used it much because it was a hassle to tune it and to change the amplifier settings.  It also produced constant RFI problems, which discouraged my use of the lower HF bands for quite some time. However, as I made improvements to the shack (in terms of automation) the tuning hassles and amplifier settings were no longer an issue.

But the RFI was another story…Did I mention the shack is on the second floor?

I was experiencing terrible RFI problems in the shack and in other locations within the house. Any TX on 30m or below was a complete disaster. I was getting RF in all the PC’s in the shack, and several appliances in the house as well.

I realized it was time to get things in order with the dipole once and for all.

As I began planning for my recent remodeling of the shack, I added RFI mitigation to the list of things that required research. I needed to be able to operate at full output on every band without concern for RFI. It seemed like a daunting task at the time given my limited knowledge of the subject.

I decided to re-examine every aspect of how things had been connected previously. From the routing of the cables, to the physical separation of certain components, to my (less than adequate) station ground. It wasn’t long before I had developed a fairly comprehensive approach I was certain would resolve the problem once and for all.

It made no sense whatsoever to proceed with building the station if these issues were not completely resolved. So after some careful research I found a few documents that outlined exactly what needed to be done.

  1. Amateur Radio Station Grounding and Lightning Protection – by W5BWC
  2. Common Mode Chokes – by W1HIS
  3. Mosley Electronics MP-33N Docs
  4. Ferrite and Chokes by KF7P

My ‘take-away’s’:

From the grounding doc:

  • Install a Low Impedance Ground
  • Utilize Single Point Ground System

From the Choke docs:

  • Build a High Power W1HIS design RF Choke
  • Install Clamp-On Ferrites on both ends of every cable

From the Mosley doc:

  • Install a 5 turn coax choke at the feedpoint

From the KF7P website:

  • Use “MIX 31” ferrite material

I detail the actual installation of the grounding, chokes etc. in the Rack Mounting Project blog. Rather than rehash that here, let’s talk about the results.

Another key ingredient was the addition of the AT-AUTO antenna tuners. These tuners keep the SWR to an absolute minimum. Now that the linear amplifier is properly connected to a Low Impedance ground, it functions flawlessly. And finally, with the addition of the Mix 31 ferrites, the entire system is indeed much quieter. Noticeably quieter RX. And finally, all RFI has been eliminated.

There was no better proof of this than the performance achieved during this years CQWW WPX SSB contest. I operated on 80, 40, 20 and 15 meters, at full output, with no trace of RFI anywhere. No doubt the installation of the massive W1HIS choke was effort well spent.

W1HIS Choke
The W1HIS choke design helped completely eliminate the RFI problems I was experiencing.

In the end my “Compromise Dipole” at roof line elevation, did a surprisingly good job. I worked into South America, New Zealand, Japan, Hawaii, Europe, the Caribbean, and Canada on 40 and 80 meters. This dipole antenna has finally yielded some good use!  (I call it a ‘zero to hero’ transformation)

I finally have a fully operational station. Fully automated, that can work on any band in any mode, at very low SWR, with quieter than the previous installation. More evidence of time and money well spent.

Numark Production Hub

Numark Production Hub

I came across the Numark Production Hub today and decided this was something I could use to solve a few issues.

  • Power outlets are needed on the desktop
  • A USB hub is needed for the W7 PC
  • A high current USB charging port is needed

The Numark Production Hub is an AC outlet strip with a USB hub built-in. The “production” moniker is a marketing buzz word aimed at today’s audience of young “producers”. Hi Hi!

In order to make room for the Samson SM10 audio mixer, I had the move the 1U Monster Power PRO-2500 to the rear of the rack, which cost me two AC courtesy outlets.

Moved to the rear rack rails
Monster PRO 2500 was moved to the rear rack rails in favor of the SM10 mixer

Additionally, The Windows 7 PC only has two USB ports on the front, and they are not enough by a long shot.

AC Power with USB Hub
Numark Production Hub

I also like the fact that Numark mounted the AC sockets at two angles to allow insertion of “wall warts”.


The high current charging port sealed the deal
4 USB Ports and a 2.1 amp USB charging port

Even though the sockets appear at a different angle in the close up, they are indeed mounted as shown in the top photo. The deciding factor for me on this purchase was the 2.1 amp charging port. I have some 2200mah batteries in the shack that should charge much quicker on this port than they currently charge using the PC USB port.

We’ll see how it holds up to RF. If it is susceptible, and ferrites don’t help, I’ll return it. All in all, the Numark Production Hub fits the bill in this case.

MFJ-1708 Automatic Antenna Switch

Today I checked out the new MFJ-1708 RF Sense Transmit/Receive Switch

MFJ-1708 RF Sensing T/R Switch
MFJ-1708 RF Sensing T/R Switch

This neat little MFJ automatic T/R switch senses transmitted RF and switches your antenna from receive to transmit using a relay. It shorts your receiver antenna input to ground to protect your receiver. It also provides an auxiliary contact closure to ground during receive (opened in transmit) for an “On-the-Air” sign or other use, perhaps even a TX Interlock line. The adjustable delay means I can fine tune it for perfect open/close.

Instead of using RF sense to switch the antenna, a control line input lets your key/keyer or PTT line switch the antenna. An adjustable time delay circuit gives you delayed switching. This prevents your antenna from switching between dots and dashes or between syllable and words.

Works on all modes — CW, AM, SSB, FM, and digital modes. It handles 200W SSB PEP. Compact 4 W x 2 5/8 H x 1 1/2 D inches.

It has SO-239 coax connectors for antenna, transmitter, and receiver. It has control input, auxiliary contact closure to ground, time delay screwdriver adjustment, power jack. Requires 12 VDC or 110 VAC with MFJ-1312D

I plan to use this switch so I can listen on my IC-765, but transmit from my Flex 5000 HF port. The MFJ-1708 is rated for 200 watts

Behringer Eurorack Pro RX1602

Before purchasing the Samson SM10 mixer I did a little more research and revisited the Behringer product line. The Behringer Eurorack Pro RX1602 mixer fits the bill at a fraction of the price of the SM10.


Behringer Eurorack Pro RX1602

Behringer Eurorack Pro RX1602

BEHRINGER EURORACK PRO RX1602 Professional Multi-Purpose 16-Input Ultra-Low Noise Line Mixer
  • Extremely flexible multi-purpose sub-mixer, multi-track monitoring mixer and level translator
  • 16 balanced high-headroom line inputs for individual stereo or mono use of each section
  • Ultra-low noise ULN design, highest possible headroom, ultra-transparent audio
  • Dedicated balance and level controls plus +4/-10 level selection per channel
  • Monitor/FX Send control per section with global master send control for flexible monitoring, recording or effects applications
  • Illuminated double-function “mute” button per section with additional “clip” indication provides comfortable input source/level information
  • Monitor/FX signal assignable to phones output for added flexibility
  • Highly accurate 2 x 7-segment LED level meters and individual level control for left and right main mix signal
  • 1/4” TRS main mix outputs plus easily accessible headphones output on the front panel with dedicated level control
  • High-quality detented rotary controls for long-term reliability
  • Shielded toroidal power transformer for lowest noise interference
  • High-quality component components and exceptionally rugged construction ensure long life

Behringer and Samson are very similar in build quality, features etc. so the Behringer Eurorack Pro RX1602 is a direct replacement for the Samson SM10.

Intended use:

  1. FLEX 6300 (L/R)
  2. FLEX 6700 (L/R)
  3. FLEX 5000 (L/R)
  4. W7 PC AUDIO
  5. W10 PC AUDIO
  6. PRO 2006 (MONO)
  7. SPARE
  8. SPARE

I’ll set all the inputs at  -10db sensitivity, and run the balanced SEND output to the Flex 6700 Line Input. No change in functionality, although the Samson has more features, they are not features I need for this application, nor are they features I need to pay more for.

UPDATE 11/24/18: The Behringer ‘bargain’ mixer failed after a few months use, and was replaced with an SM10.

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Palstar AT-AUTO Mod

This is an interesting modification for the AT-AUTO. This mod adds a second SO-239 coaxial output in place of one the posts normally used for the “balanced” antenna output. It’s a Palstar AT-AUTO Mod that I think I may need one day. The instructions are simple and I found a few photos of modified units on the web.

I found this information on the Kessler Engineering website:

I have an AT-AUTO but I need a second coaxial output. Can I remove the balun and replace that with a second SO-239 connector? What is the best way
to do this? How would I know which coax output I’m using?

You have two options. We would prefer that you purchase the accompanying CX-AUTO which provides eight coaxial outputs. However, if you prefer to simply add a second coaxial output and don’t need the balanced output, we recommend the following procedure:

  1. Unsolder the balun lead at the antenna relay.
  2. Remove one of the balanced output connector “Bolts” and associated nylon insulating hardware.
  3. Insert an SO-239 connector in the vacated balanced output connector.
  4. Solder a #14 wire from the center-pin of the SO-239 connector to the relay contact which previously went to the balun.

If you follow these steps, this modification can readily be “undone” and no added holes, etc. will be necessary. The firmware will associate the “new” coaxial output with the “Balanced” memory settings, etc., and will be selected whenever “balanced” or “bal” is shown in the AT-AUTO display.

Palstar AT-AUTO Mod
I’ll use a ‘bulkhead’ type so-239 connector (like the others), not a panel mount. No drilling.

Here’s an inside view of the Palstar AT-AUTO Mod:

Palstar AT-AUTO Mod
The balun is disconnected and the jumper is installed in its place (lower left)

I currently have two HF wire antennas on the roof that I am not using. If I perform this mod on both of my AT-AUTO’s I could regain use of both of these antennas, a G5RV, and a second 130ft dipole (in a different direction than the ‘main’ dipole. aka [DIPOLE1]

Astron RS-70A Regulated Power Supply

Astron RS-70A Regulated Power Supply

I purchased the Astron RS-70A Regulated Power supply after obtaining less than desirable results from some of the smaller Astron supplies. I’d also accumulated a few too many of the small Radio Shack 12v supplies. As everytime one was taxed, I’d just add another one.

Astron RS-70A regulated Power Supply
I decided it was time to invest in the last power supply I would ever need


I went through several of the Astron 20 and 35 amp models early on (during my ICOM days). Believe it or not, every one of my Radio Shack supplies have not only survived, but remain in service to this day, after decades of 24/7 use. If you look through some of my shack pictures over the years you’ll no doubt notice them!

Radio Shack 12 volt Power Supply
I have several of these in continuous operation since the 1990’s

I found my RS-70A on eBay of all places. Someone bought it for a project that fell through and dumped it on eBay at half price. Lucky for me, this was yet another bona fide ‘score’. It arrived in a rounded out cardboard box, but luckily, made the trip unharmed. It was obviously brand new. I almost felt bad for the seller.

Astron RS-70A Regulated Power Supply
Plenty of ‘headroom’ in the RS-70A at 57 amps continuous

Astron RS-70A Regulated Power Supply Specifications:

Fold-Back Current Limiting Protects Power Supply from excessive current &
continuous shorted output.
Crowbar Over Voltage Protection
Maintain Regulation & Low Ripple at low line input voltage.
Heavy Duty Heat Sink
Chassis Mount Fuse
Three Conductor Power Cord


Input Voltage 105 – 125Vac
Output Voltage 13.8Vdc +/- 0.05Volts (internally Adjustable 11-15V)
Ripple Less than 5mV peak-peak (full load & low line)
Continuous Duty 57 Amps
ICS 70 Amps
Size 6″ x 13-3/4″ x 12-1/2″
Shipping Weight 48 lbs.

Astron RS-70A Regulated Power Supply
The ‘business end’ of the RS-70A

I have my Flex 6300 connected directly to the RS-70. I also directly connected an MFJ-1118 DC Power Panel to supply 12 volts to the rest of the 12v equipment in the rack.

I am currently on the lookout for a second RS-70A to keep as a backup. My current RS-70 is a central point of failure and redundancy is a must. I doubt I’ll find another new one at half price, but when I find one with the ‘right’ price, I’ll have a spare!

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Mosley TA-33-JR-N WARC

My Teenage Mosley TA-33-JR-N WARC

My Mosley TA-33-JR-N WARC Multiband HF Yagi is going to be 14 years old next month. I’ve never had a single problem with this antenna. It has been installed on my roof tower since May 2004. I’ve worked the world with this “Junior” antenna!

Back in October 2016 I began seeing high SWR numbers and decided to go up on the roof and take a look. Here’s what I found:

Mosley TA-33-JR-N WARC
This is LMR-400 after 12 years in the Southern California sun

OK, before you say it, yes, this is Times Microwave (the genuine article). The outer jacket had disintegrated in the sun. I noticed the increased SWR after it had rained one day. Further, it had seemed to improve after a few days, and I reasoned this was because something had dried out.

Mosley TA-33-JR-N WARC
Feed point connection on the TA-33-JR-N WARC

I was concerned these bolts might not come out very easily. However, with some gentle taps they came right out. Some evidence of corrosion can be seen. When I installed this antenna in 2004, at the suggestion of one of my elmer’s at the time, I sprayed the elements and boom with Krylon ‘clear coat’ to help prevent corrosion. I think it was a sound decision, since the antenna still looks great overall considering its age.

Mosley TA-33-JR-N WARC
Of course, I had to replace the sun damaged feedline

Mosley TA-33-JR-N WARC – Coax Balun

At the suggestion of the fine folks at Mosley, I added a 6 inch (inside diameter) loop consisting of FIVE turns of the new LMR-400 Ultra Flex coax.

Mosley TA-33-JR-N WARC
The Mosley engineer told me to mount it on the boom close to the feedpoint.

Mosley TA-33-JR-N WARC
The patented Mosley Feed System

From the Mosley website:


Feed Systems – The Simpler, The Better…
Despite popular belief, linear radiators, normally employed in 2 and 3 element parasitic arrays, have a driving point impedance of close to 52 ohms when open at the center. To feed such a radiator it is only necessary to connect a 52 ohm line at this point to achieve the best possible match of line to antenna. However, because of certain design characteristics, some beam antennas require elaborate and, sometimes, unstable matching devices such as Gamma or T-Match systems or variations of these systems. Such devices are usually difficult to adjust and to maintain in adjustment when used in multi-band beams.
MOSLEY TRAP MASTER beams, however, are so designed as to not require any unwieldy matching arrangements. Mosley beams are fed by connecting the line directly to the open center of the radiator. Thus, an excellent match is achieved over the entire width of each Ham band resulting in extremely low SWR near resonant frequencies of each band and the ability to range from one end of the band to the other without excessive SWR. By eliminating such matching devices, MOSLEY TRAP MASTER beams provide their users with stable and dependable operation without the necessity of frequent trips to the roof or up the tower
to make readjustment.

Mosley TA-33-JR-N WARC
New coax in the harsh California sun!

The end result was well worth the bit of effort it took to add the coax balun. The antenna exhibits excellent SWR. The Mosley TA-33-JR-N WARC will be my main HF antenna for the foreseeable future, and certainly, for as long as I live at this QTH.

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