Day 4: Testing and Redesign

 

OMG is the best way to describe how well the receiver works.  I am seeing DX roll in from all over the globe on all bands.  This morning I saw Algeria on JT65.  I’m even hearing signals on 160 meters at night.  I had never heard any JT65 station on 160 before. I am thrilled with the first results.

We got Internet access hooked up and to the surprise of all the system worked on the first try for receive.  At home I pressed the ON button and the receiver came alive.  But then came time to transmit.

I tried transmitting and the SWR was infinite.  The auto tuner in the rig flashed an error.  Loose cable?  I hadn’t retuned the PAR EF-20.  Could it be far enough off?  Time for a trip to the site.

At the site I noticed I could wiggle the coax and get different results.  Bad connector on the coax. I could see the connector was soldered but it appeared to be a cold solder joint. Returning home I made up an entirely new cable and made sure the connector was hot enough to melt solder on it’s own.  No cold solder joints now.  I drove back down and replaced the cable.  I also re-tuned the antenna to dip the impedance exactly at the JT65 frequency of 14.076 MHz.

Interference from the solar controller was now noticeable.  I snapped on some toroids and that quieted the noise considerably but not completely. I also notice some birdies caused by the Internet receiver.  Back home and the SWR is now very low.  The rig is acting normal now.  Time to try the first contact.

The other shoe dropped when I cranked the power up to 25 watts and tried to make a contact.  “RF in the shack” crashed the remote.  I had to drive down and reset it.  Upon arrival I discovered all of my equipment was still running.  It was the Internet receiver that had locked up from the RF.  Back to the drawing board.

My first trial at fixing the problem will be to add more toroids but more importantly I will separate the antenna away from the equipment location.   I ordered 100′ of coax to allow the antenna to be relocated.  When the toroids and the coax arrive I will find out if this helps both the EMI to my receiver and the RF into the Internet receiver. Check back for the update on the results.

coax

Meanwhile I am just listening and comparing received signals with the RF Space Cloud-IQ sdr remote receiver I have access to.  Results so far are neck and neck.  Many stations have an identical SNR report on both units.  A small per centage have different readings and some drastically different readings.  Speculating I would say that’s the different polarization between the vertical antenna on the Elizabeth receiver and the horizontal dipole on the Cloud-IQ.

 

 

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Day 3: Decisions

Stepping back to explain our choices.  All engineering judgement involves compromises to accommodate important factors like money, space, availability, and what one is comfortable with or what one already has experience with and so on.  Choices we made are strictly ours and your choices will be controlled by your own engineering judgement.

My Givens:

  • A feeling at home of sitting in front of an actual radio
  • No pc on either end
  • Knobs and an actual front panel
  • As little duct tape and baling wire as possible
  • Will receive as well as the Cloud-IQ remote sdr receiver I’m already using
  • Must work with JT65 digital mode but be capable of CW and SSB, too ( I am a JT65 junkie but I don’t want to give up the other modes totally).

Transceiver

Perhaps the most key decision is what radio to use.  My choice is the Kenwood TS-480SAT.

ts-480

Kenwood TS-480SAT

Information at:   http://www.kenwood.com/usa/com/amateur/ts-480sat/

 The decision was made easy for me because I already had the TS-480 on hand.  It had been my HF mobile rig for a few years and was available now.

A separable front panel makes things a lot easier for a remote operation.  All we have to do is simulate the umbilical cable over the Internet.  There are only a few models that have this feature.  Elecraft goes one step further with the K3/0 which has a front panel mounted on an empty radio cabinet.They also have a K3/0 Mini which is just the front panel without the empty cabinet. Had I not already had the TS-480  I probably would have chosen the Elecraft K3,K3/0 Mini combo. A key requirement was whatever radio I choose must work with the RemoteRig interfaces.  Either of these radios have that capability. When it comes to dynamic range I had some reservations that the TS-480 might not have the best receiver and I believe the Elecraft does have the best. I promised myself if the Kenwood doesn’t work out I’ll switch to the Elecraft.

Interface

I already gave away my choice on this one.  It’s the Microbits Remote Rig model RRC-MkIIs.

1258MkII-two-boxes-400x240

Remote Rig RRC-MkIIs

Information:    http://www.remoterig.com/wp/?page_id=1051

An interface should take away headaches not cause them.  There is a lot of good competition that I considered.  Many need a pc at one end or the other (or both) which is a deal killer for me. I’ve tried to keep pc’s running in unheated hutches with strange power before. It’s a challenge. Remote Rigs have processors built in at both ends.  These units are as close as possible to being a transparent connection between the TS-480 base unit and control panel. No pc at either end. They satisfy the requirement of replacing the umbilical cable with the Internet.  I could not tell any operational difference on the bench when I was testing between the Kenwood supplied cable and the Remote Rigs running over the Internet.  Some of the competitors require a pc to control the radio remotely AND a separate Skype connection for voice.  What a headache.  When I read Remote Rig has it’s own built in automatic Skype connection included I was sold.

Remote Rig (Microbits) has new models coming out all the time.  Since my purchase decision Remote Rig has made available “twin mode” models.  It requires two identical transceivers.  One is at the remote site, the other on your desk at home.  Every operation you perform on your desk is duplicated on the remote transceiver.  Certainly not the least expensive option but it has one real advantage.  When troubleshooting at the remote site just putting the TS-480 in transmit mode requires heroic efforts.  I have to drag my Remote Rig control unit and TS-480 front panel to the site each time, along with some way to power it and to access the Internet.  Having a full transceiver would eliminate that chore and make troubleshooting much easier.  At home that desktop transceiver would feel like a real transceiver…because it is! I like RemoteRig’s update.

Power Monitor

4005i-bigZoom

Rig Runner 4005i

Information:  http://www.westmountainradio.com/product_info.php?products_id=rr_4005i

This isn’t a critical need but it sure makes power control comfortable.  I hadn’t even considered this item until I ran across it at Dayton and started discussing what it does.  It controls power ports over the Internet so I can power cycle a single piece of equipment without driving to the site.  It has fuses built in.  Not just ordinary fuses but poly fuses.  This means if one blows it restores automatically once the fault is cleared. Again no trip to the site (unless the smoke got out).  It also displays amperage and voltage on each port.  Nice for piece of mind.

Internet

Internet access is that so called umbilical between the radio and the front panel — a very critical component.  Latency should be low, probably below 100 ms.  Can you ping the site with return times of less than 100 ms?  Satellite internet is typically 350 ms.  I was afraid to try satellite because of it’s long path delay.  Local wireline carriers were not a possibility because our site is a half mile back from the road.   Ethernet won’t go that far.  Wifi would require a power source.  Cell phones might work but the monthly charge for unlimited data is prohibitive.  Wireless internet access is the perfect solution if one is lucky enough to be within a coverage area.  The have fast latency and they can put a receiver anywhere there is a signal.  Fortunately we spotted a tower nearby and knew we could get service.  A requirement is access from the outside world so we needed a static i.p.  Without it we would have been given a private i.p. which is not accessible from the outside world.  Our good fortune is thanks to this company:

directlink

Information:   http://godirectlink.com/

We chose their least expensive offering because we don’t need much bandwidth.  We are using voip (voice over internet protocol) service which requires 100 Kb each direction.  Our service provides 12 Mbps so it’s a huge overkill.  Controlling the rigs and accessories requires only a few additional Kb.

Note: If we had line of sight between our home shack and the remote we could have set up our own link.   We would be looking at Ubiquiti Nano Stations or similar for a range up to 10 miles.

Router

I chose the first old router I could find stored in a closet somewhere.  It happened to be the Linksys E2500 from a few years back.  I was happy that it’s power jack specified 12 volts.  Most routers I have seen will run on 12 volts despite whatever voltage they say because they have a regulator inside.  Any router is fine new or old.  We are just going to use it to set up port forwarding and we don’t need much processing power for the small bandwidth we will use. We don’t need wifi but I am using it because it’s easier to connect to the system when I’m at the site. Wifi draws an extra .14 A from the power budget.

router

Linksys E2500

Information:    http://www.linksys.com/us/p/P-E2500/

This is the Linksys E2500 but I suggest you use the first available router your hands touch from any source as long as it’s legal.

Solar System

Obviously this section is optional if you have access to ac power at your site already.  We don’t. Actually we do but we wanted to stay off the grid, and what a great opportunity to learn more about the latest solar technology. The biggest challenge was figuring out what capacity we needed.  We got a rule of thumb from a local solar dealer who said he had set up solar systems for hams’ remote bases before.  He suggested 400 watts and a PWM controller rated at 10 A per 100 watts.  I could count up the usage of things that run 24 hours like the router and the Remote Rig.  What was perplexing was guessing how many hours of radio operation I should plan for.  How much listening time and how much transmitting time?  In the end I just took a guess and went with the dealer’s numbers.  I used NREL’s solar calculator site

http://pvwatts.nrel.gov/

to determine how much sunlight in Colorado, and at what angle the panels should tilt.  I only bought three 100 watt panels because the mounting for 4 would have doubled the cost.  Amazon had free shipping and no sales tax on panels and the price is coming down all the time.  I chose a 30A controller from the same company, Renogy.  Battery capacity totaled the same amp-hours as the panels produce minus the equipment load. Rather than a commercial mounting I used perforated angle iron from Home Depot and staged it in the back yard.

2016-01-21 10.28.43

Here’s what the panels look like after being moved to the site.  By the way the camera is pointed toward Europe so this is what it’s look like toward the DX.    Exciting.  Can you see the Eiffel Tower?

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Day 2: Installing the Radio Equipment

On Day 1 we had bought a Jeep to get through the mud and installed solar panels.  We also bolted on a vertical antenna and a pole for the Internet receiver. Anticipating an exciting time ahead.

2016-01-30 15.04.13

Ready for the next step which is to add the cabinet with the radio and other electronics.  Inside the cabinet we have a solar charge controller, a power monitor, batteries, a router, and of course, a transceiver.  Here it is with the door open on the floor of the shack at home tested and good for the big move.

2016-02-04 07.57.21

This was built months ago even though I didn’t have a location yet.  I wanted to be ready.

Transceiver:   Kenwood TS-480SAT

Interface:  Microbits RemoteRig Model RRC-1258 MkII

Solar Charge Controller:  Renogy Wanderer 30A PWM

Panels:  (3) Renogy 100 watt Monocrystal

Router:  Linksys E2500

Batteries:  PowerStar SLA AGM 12V 35AH

Power Monitor:  Rigrunner 4005i

Vertical Antenna:  LNR/PAR EF-20 attached to Spiderbeam 12 meter telescoping fiberglass pole

 

It didn’t take long to bolt the cabinet in place and hook up the LMR-400 coax to the antenna.  Notice the 8′ ground rod.  Lightning season is just around the corner. Also a few toroids were snapped onto various leads. At this point we’re ready for Internet and testing.  Will it all come up and work as we want?

2016-02-13 10.27.46

Day 1: Finding Out

Here we are in January, 2016, at the very beginning placing solar panels with Steve’s shiny new steel building in the background.  It was late October, 2015 when I got an email from my old friend Steve offering space  for a small remote base on his new acreage after the holidays.  I had been looking to buy a lot or cabin of my own for over a year.  Always something was wrong.  It was too expensive, too far away, too small, too run down, no Internet access.  Other friends had offered to let me use their stations remotely but if I have to resort to remote operation it at least needs to be my own station. So I gladly accepted Steve’s offer.

2016-01-30 12.56.48.jpg

The acreage is located near Elizabeth, Colorado on the prairie 40 miles southeast of ( and 1300 feet higher than) Denver not too far from the Palmer Divide. We’re at an altitude of 6600 feet and we are an hour’s drive from home.  Steve has spent the last months having a steel building erected.  It is a half mile back from the road.  The car tracks to the building were very muddy the first day I visited and my car had no chance.  After Steve gave me my site tour I began shopping for an affordable 4 wheel drive vehicle to get through the mud.  I found this good old Jeep Cherokee and it really does a good job on the mud.

I rationalize this expense and all remote base costs the same way.  It’s to get back to even before we downsized.  When we made our decision to downsize I promised myself I’d make a good effort at DXing with restricted antennas. If it didn’t work I would set up a remote base. I tried DXing for a year and a half but had only moderate success. Expenses have to stay within reason because I didn’t have a huge station before (also, I’m not rich).  But I could work DX at the old house and that’s my first love and I want to get back to it. Here we go.

2016-01-30 15.05.37

By the end of Day 1 we had made some fast progress.  The panels were installed along with poles for the Internet equipment and a fiberglass pole equipped with a PAR/LNR EF-20 twenty meter vertical half wave.