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Setting up my Remote station


#61

It’s been a while since I posted anything about this, and it seems that a couple of people were interested in this.

After a few problems and false starts, the system is now up & running.

Here is an update on the equipment side of things. There is a separate thread in which the antenna arrangements are discussed, so I will post updates to the antenna system there. This is specifically about the equipment side of things:-

Equipment:-

RemoteRig boxes

Yaesu FT-857

mAT-30 automatic antenna tuner


Solar panel, plastic salt bin housing the equipment and 4G antenna


Batteries and the two equipment boxes inside the plastic salt bin.


Inside the first equipment box:- router, solar controller & regulator.


Second box contains:- the radio, one end of the RemoteRig, antenna tuner & a remotely controlled reset switch.


Earthed at the box.


Also earthed at the base of the mast.


Temporary mast.

For those of you who are unfamiliar with the RemoteRig devices, they basically allow you to place the radio at a remote location (in this case a 3 acre field which I own about 45 minutes drive from my house), and the original control head unit from the radio goes in the shack at home. It basically uses the internet as a very long separation lead.

All sounds relatively simple, but I ran into a lot of problems which needed to be overcome:-

Problem 1

The earlier versions of the RemoteRig don’t natively support the FT-857 without either a modification to the RemoteRig boxes, or modified cables between the RemoteRigs & the Yaesu FT-857 (both the radio & control head).

The later versions of the RemoteRig don’t have this problem. They support the FT-857 without having to manufacture modified cables.

As I purchased the RemoteRig boxes second hand from a well known auction website, mine are the older version which does not support the FT-857D, so I built up the required cables from drawings on the manufacturer’s website.

Problem 2

Having got the radio working perfectly over my own internal LAN connection at home, the time came to try to separate the two halves using the internet & a 4g connection.

Total nightmare!!! I won’t bore you with the details. You can read the earlier posts to find out about this if you are really interested (or very bored).

After sorting out the networking problems, I now have a 4g router running with a fixed public IP address.

The 4g signal isn’t that strong at the radio site, so an external antenna is required.

I can’t remember where I read it, but I recall reading that the router requires a stable 12v power supply. Higher voltages (such as 13-14 volts often seen from leisure batteries and solar chargers) can apparently damage the router. A voltage regulator was installed for the router to overcome this

Problem 3

According to the RemoteRig manufacturer, the Yaesu FT-857 creates a very brief short circuit (or very close to a short circuit) during power on. This can reset the RemoteRig box when you turn the radio on, causing several problems.

Sure enough the radio tried to turn on, then turned itself off when the RemoteRig box lost power. It was impossible to turn the radio on with the radio & RemoteRig box on the same power supply.

According to the manufacturers, the fix for this is to use a separate power supply. For this reason, the RemoteRig box is powered from the regulated power supply that runs the router. This is taken from a separate leisure battery

It means that I have to have a second battery, which is a pain but not the end of the world.

In some ways, this is actually a better arrangement as I want the router and RemoteRig box to stay alive even if the radio fails (so that I can maintain control & turn things off remotely if required).

Problem 4

Damn my choice of radio!!!

Don’t get me wrong…….I like the Yaesu radios, and I like my FT-857. Unfortunately it just seems that there are several quirks with them when it comes to controlling them remotely!

According to the RemoteRigs manual, the FT-857 can reach a state where it becomes unresponsive and the only way to recover it is to remove the power from the radio.

So far this has not happened to me yet, but given the problems if the radio becomes unresponsive (not least the 45 minute drive each way to get to it) I didn’t want to take the chance of this happening and have no way of resetting it.

I had to find a way of doing this remotely without shutting of either the router or the RemoteRig box.

RemoteRigs recommend a relay controlled via the I/O port on the RemoteRig, which can be turned on/off remotely.

According to Yaesu, the radio can draw up to 20 amps, so a reasonably heavy duty relay was added to switch the power to the radio.

Problem 5

The equipment would be outside in some fairly harsh weather conditions, so would need to be protected.

The really expensive or delicate equipment (radio, RemoteRig box and antenna tuner) was built into an old military ammunition box, which is sealed. Any holes that I drilled for cabling were resealed with sealant or rubber grommets.

A separate box was put together to contain the router, solar charger, and possibly later a Raspberry Pi (to run digital modes such as FT8).

The entire system (the two batteries with solar chargers, and the two equipment boxes) is housed inside a large salt bin with a padlock to keep the worst of the weather off of the equipment and hide it from opportunist thieves.

If anyone is contemplating setting up a remote station like this, I feel obliged to include one word of caution for if you are going to enclose batteries like this. Batteries can give off explosive hydrogen gas when charging. The battery bay should be well ventilated for obvious reasons. Just look at what happened to the Hindenburg to see what history teaches us & to understand why this could be a big problem!!!

Problem 6

Powering the system.

The system will be installed on a 3 acre piece of farm land with no utility power or services.

Batteries and solar panels it is then!

After measuring the current draw on the system (from both batteries/power sources) and several calculations later, factoring in significant inefficiencies in the solar panels for our British weather to give me some reserve, I came to the following conclusion:-

I need a 110Ah battery for both the radio & the router to get meaningful use from it. A 150 watt solar panel and a solar controller capable of charging two batteries takes care of charging up the batteries each morning.

With the current setup I get between 1 & 2 hours of use depending on how much power I run (longer if I only receive but don’t transmit).

I plan to add another 110Ah battery for the radio (so a total of 220AH on the radio, and 110Ah for the router) to give me more operating time. Probably also another solar panel as & when budget allows.

The teething problems

Upon initial installation, things seemed to be working well, until the batteries stopped charging and the whole setup started to discharge the batteries. A drive to the field found that the brand new solar charger had failed. That’s what you get for buying cheap from abroad!!!

A replacement solar charger and the system went back to the field. Faultless operation for about 2 days (the estimated duration that the system would stay alive before the batteries died if they were not charged by the solar) and then it died. Not the bloody charge controller again?!?!?!

Another trip to the field with a volt meter revealed that both of the batteries were fully charged. Maybe a fuse had popped……No, the fuses were good. Good voltage was being supplied to both boxes……….continuity along all of the power cables. What’s gone wrong this time then!!!

I stood in the middle of the field scratching my head in total bewilderment. I was just starting to remove the system yet again to take it home for more detailed inspection when I heard some relays start clicking randomly when I juggled the wires. Another check with the multi-meter confirmed that one of the earth wires was bad.

It wasn’t a complete break but the resistance in the earth wire was rising from 0 Ohms between the battery and the negative side of the control (which you would expect to see 0 Ohms), to several Ohms. This was resulting in a voltage drop to around 7-8 volts, causing the system to shut down!!!

I was able to replace the earth wire on site as I had brought plenty of tooling and spares with me.

About a week later, having completed some on air tests with several friends near London, several SOTA chases and numerous contacts around the UK & across Europe on both 40m + 80m, the system now seems to be working flawlessly.

I’m a happy bunny!!!

Next steps

Initially I started with a trapped dipole for 40m & 80m at around 6 meters above the ground. This was always intended to be a temporary measure to iron out the teething problems.

The antenna is actually resonant further down the band on the CW portion, not the SSB portion where I’m trying to use it. This is taken care of by the tuner, but it’s not ideal (as the antenna isn’t as efficient as it could be).

With a bit more time to plan, having proven the basic system & after a couple more paydays have passed, I will think about changing the antenna for something a little better.

My current thinking is a 160m sky loop at around 10 meters above the ground. I’m considering putting up a ¼ wave vertical for 20m and some kind of antenna switching arrangement, maybe also a vertical for 2m………one step at a time though.


#62

A big electrolytic across the rails close to the radio to provide the switch on current.

I hope it didn’t smell of vinegar whilst curing.


#63

Congratulations, James! :clap: :clap:
If I were you, I’d go for a multiband antenna for HF (dipole or vertical with elevated radials) and a dualband vertical for 2m/70cm. You may not have the best performer antenna in the world but asuming you will trim/adjust it correctly for low SWR on all the band sections you are going to work on, that way you’ll be able to get rid of antenna tuner and an antenna switch, which are 2 potential failing things less.
Good luck and keeps us informed with your next steps.
73,

Guru


#64

A big electrolytic across the rails close to the radio to provide the switch on current.
[/quote]

I considered this but wasn’t completely sure if it would work. After all, doesn’t a 110Ah battery act as a large capacitor which can supply a fairly large belt of current in one go?

I could be completely wrong about that!

Either way, I wanted to be able to keep the router and the control (switching) side of things alive even if the radio battery is depleted, so felt more comfortable having a second battery and keeping the two parts powered separately.

Especially as the internet connection may eventually get used for other applications (possibly security or control of other equipment such as irrigation).


#65

Obviously not in your case :wink:

Having 2 supplies is probably easier than having to have some kind of load shedding to stop the radio depleting things so it all ends up broken.


#66

Hi James,
This is why I recommend you a multiband antenna. See below the SOTAs I have just chased in multiple bands within a few minutes using my remote station.

The antenna is far from being a good performer on any band but it’s got low SWR on all bands and it performs good enough as to chase SOTA activations in Europe. When it comes to DX activators, my inverted vee broadband folded dipole is too deaf and I very rarely can copy any from North America. Let alone JA and VK-ZL.
73 and have a nice weekend.

Guru


#67

Hi Guru,

I’ve yet to set up the permanent antenna (time & budget constraints).

For test purposes I have temporarily set up a trapped dipole for 80m & 40m, so technically do have duel-band capability with it. Unfortunately I can’t operate remote on 20m at the moment, which is a shame as that is probably my favourite band.

The plan is to put up a 160m full wave loop at about 10 meters above the ground, which should also be usable on 80m, 40m & 20m. So I will eventually have multi-band capability.

In the long run, I plan to use the switching capability on the RemoteRig to operate an antenna switch. I would ultimately like to set up a vertical for DX chasing on 20m & maybe also 40m.

I’m thinking that it might be possible to set up a vertical element which would be a half-wave vertical for 20m & a quarter-wave vertical for 40m. It’s then a case of switching between the matching circuits (which should be possible by using the switching capabilities of the RemoteRig to switch relays). I’ve yet to sit down and do the maths, but it’s a theory.

I’ve been impressed with the results so far though.

I wouldn’t consider myself to be a heavy chaser. If a spot comes up I will chase it if I have a few minutes spare. In the two weeks that the remote system has been operational, I have collected around 50 points from “extremely casual & relaxed” chasing. That is a quarter of the total number of points that I collected in 2018, in just two weeks!

All food for thought. I think that the 160m loop is the next big project though.


#68

Hi James,
That seems to be a good move. Since I believe you are not a CW operator, you don’t need to bother with 30m. I have the impression that 80m is an interesting band for SOTA in your area with quite a good number of activations working that band.
We very, very rarely hear any activators on 80m here. I think I might have only chased 1 or 2 activators and I’ve never activated on 80m.
I have started to activate on 60m this year from time to time and I have also chased a few activators on 60m. It seems to be a quite interesting band in these days of very difficult conditions for short skip contacts on 40, 30, 20m
Will that loop you are planning to install be able to work on 60m too?
If so, you will cover the most interesting bands in these days for SOTA chasing.
73,

Guru


#69

Not yet, but im in the process of learning CW.

I occasionally run FT-8 on 30m from home but don’t plan to set up the remote system for CW or digital modes in the near future.

In the long run I might try to set up a Raspberry Pi to run FT-8 remotely but that will be quite some time before I start working on that.

To that end, as you rightly said, it’s not really relevant to the remote setup at the moment.

Absolutely. We do seem to have quite a mix. Most UK activations seem to happen on either 2m, 60m or 80m.

I would say that most of my chasing is on 40m, with 80m not far behind.

There’s only a few local summits that I can get on 2m but I do try to catch them when I can.

80m is probably the main band for UK activations, with 60m not far behind.

60m is a lot quieter (no contest activity and less people use it for reg chewing) so it makes a very good band for SOTA as you tend to get less QRM with high power stations on adjacent channels.

40m brings in a lot of European activations but the skip is a bit too long for it to be much use for chasing UK activations.

It certainly won’t be resonant. I reckon that it could be made to work with a tuner though.

Unfortunately my FT-857 isn’t currently capable of transmitting on 60m. I believe that there is a modification that can be done to wide-band the radio. It’s something that I need to look into.


#70

Hi James,
If you are currently working on learning CW, you should be able to start making some QRS QSOs in a few weeks or a month aprox. so I believe 30m will become a very interesting band for you. Would it be possible for you fitting a second loop for 60 and 30m inside the one you are planning to install for 80, 40 and 20m, both sharing a common feed line?
Perhaps it will be a bit tricky to adjust such setup for low SWR on all those 5 bands but I believe it should be possible and it should work like the fan dipoles do. I’m pretty sure someone had probably tried that before and there might be on the web something written about it.

Regarding the FT-857 ability to work on 60m, there’s a site or a forum I was reading on the web where a ham explains how to check whether your rig not having specifically the 60m band as a default selectable band can or can’t work on 60m. I can’t find it now but in a nutshell this guy said that if you go on turning your tuning knob from 3.8 MHz upwards towards 5 MHz, depending on when you can hear the click of the low pass filter relay switching, your rig will or won’t be able to work on 60m . It said that if you hear the click before reaching 4 MHz, then your rig can’t work on 60m. If you hear the click after 4 MHz, then your rig will be able to work on 60m without problems.
73,

Guru


#71

Someone else also suggested exactly the same thing to me, except we both overlooked the fact that a 60m loop would also likely be usable on 30m (may need a bit of tweaking with an antenna tuner as the two bands aren’t perfect harmonics of each other).

I believe that a Cobweb antenna works on the same principle, as does your example of a fan dipole.

It’s a very good suggestion and would be interesting to try.

I think I should get the basic 160m loop up first and then maybe throw up another loop for 60m later.

As I understand what I’ve read online (if you can trust what you read online), adding another loop will tend to cause the resonant frequency to drop, meaning that the 160m loop may have to be shortened slightly to get it tuned when the 60m loop is fitted.

This was certainly the case when I experimented with a multi-band nested (“DX Commander” style) vertical.