[VHFcontesting] ROVER Power Needs And Solutions during a VHF Contest.

[K7XC Tim Marek]

For what its worth...

I was a very competitive Single and Multi Op Mountaintop Portable in the
June VHF contests for over 20 years. In that same time period during the
Sept and January events I elected to be a highly motivated ROVER, Placing
in the Top 10 USA many times. As such I learned things along the way you
might find useful.

As to how to power your ROVER station I did all the wrong things possible
and most of the time got away with it... Most of the time... Those times
when it didn't go my way are very memorable, not to mention life changing
as in each event I had to think my way out of the situation, learning from
my failures, and never repeating them again.

With that background in mind, I recommend a pair of 6 Volt Deep Cycle
Batteries in Series, The kind that are used in Golf carts and such, as your
primary means of DC power, and here is why.

When I was a full time RVer (IE: Lived full time in a 5th wheel trailer for
2 years in TX) I had the regular 12V deep cycles replaced with a pair of
the 6V units Increasing the capacity by at least a factor of four for only
a 25% increase in Cost. We were able to dry camp for 7 days before they
needed to be recharged where a pair of standard 12V RV Deep Cycle batteries
would barely last a weekend.

As to charging them while ROVER, I would install a second 12V DC Alternator
and wire it to only charge the golf cart batteries, including its own High
Current Fuses to prevent fires as you can literally Arc Weld with this much
available Current. Some would say my plan is too extravagant and costly to
be realistic but ask yourself this... Would you even stop to think "Is it
worth it to add a new band your Rover station?"  We all know the answer is
Hell Yes, Full speed ahead, Costs be damned as I want those high value Qs
and Mults. Adding 222 almost doubled my score with all those Points and
Mults it made possible. Yet all of that is at high risk of failure if your
main source of DC power is not up to the task.

All those radios, rotors, keyers, etc are all powered in most cases with
the vehicles main battery while never shutting down the engine, which by
the way is what Ambulances do to maintain A/C and Power. Do you know why
they switched over from gasoline to diesel powered engines? Too Many Engine
fires from idling in the hot days of Summer while staged around the city
waiting to be dispatched.

What do most of us drive? Gasoline powered vehicles with charging systems
barely able to maintain the current necessary to keep it going during a
winter evening when the cars electrical system is maxed out powering
Headlights, Heater blower, A/C pump to dehydrate the air, the car stereo,
interior and running lights, not to mention the engine itself and charge
the battery. Add to that Ham Radios with aftermarket amplifiers and you
soon will find any weak link in the system and fry it.

Depending on where you breakdown (ALL vehicles will breakdown at some
point), what supplies you have on hand, and the ever changing weather, your
life may be placed at risk over the chance to play radio... Ponder that a
bit as I have been there... The vehicle dead on a tall mountain without the
needed parts on hand to effect repairs and move on. Luckily I planed ahead
and had two coolers filled with bottled water on ice and a container of
food to last several days as I waited for a friend to deliver the needed
parts to get going again.

In a Sept contest long ago I found myself  on the side of the road with a
toasted Alternator & dead battery after 3 days of driving 1700 miles while
operating an impromptu ROVER station after our Mountaintop Operation in
Central Nevada was rained out.

The truck died as I pulled into Western Reno leaving me stranded on the
side of the road till I came up with the idea to use the generator and
battery charger to get me the rest of the way home. I ended up hanging my
EX650 Honda Generator on the back of the camper shell with 16 bungee cords,
a short extension cord went over the shell in through the passenger wing
window to the 35 amp battery charger while its DC cables ran out the same
window, under the hood to the new battery I bought earlier in the day.
After 30 minutes of charging I was able to start the truck and continue.
The head lights were dim but it got me to my driveway. I'll never forget
turning off the engine after 3 days on the road, beat-up and exhausted...
only to take a few seconds to realize something was still running... The
generator dancing on the back door of the camper shell! I stopped and took
a picture before turning it off and dragging myself up the stairs and into
the house where I fell into bed fully clothed and didn't move for 8 hours.

Again I was lucky that I had in the early planning stages made sure to have
the battery charger and generator with me as part of my Emergency Tool KIt
or I would have never got home without a costly tow bill or a long walk
while exhausted to get the parts and repair it on the side of the road in
on and off rain showers, Not a fun prospect.

If I was to EVER rove again. I would have a pair of Golf Cart 6V batteries
with me in bolted down metal battery boxes running off their own Alternator
under the hood.

Just a few observations from someone who has been there and rode that style
of contesting long and hard. Being ROVER isn't for everybody... it is one
of the most demanding physical and mental forms of contesting ever known.
Lots of challenging planning, building, traveling and operating go into
each ROVER trip with no two ever being even remotely the same. I certainly
miss it but now, over 30 years since my first effort, Growing older (58)
has certainly slowed me down so I stay home and appreciate the hard work
put in by the new crop of operators who carry on the tradition.

Best of luck guys!

73s de Tim - K7XC - DM09jh... sk

Adapt, Overcome, Succeed!


On Thu, Sep 14, 2017 at 3:41 PM, Terry Price <terry at directivesystems.com>
wrote:

> On the K8GP rover we use a pair of Interstate 4DM's in parallel, about 120
> lbs each. These feed a Jacobs Electronics 100A DC-DC inverter to maintain
> 14.0 V to our TE Systems bricks which are very voltage sensitive. We also
> feed a couple of MFJ super boosters which have been very problematic and
> I'm
> planning to replace them with N8XJK regulators. These are charged by an
> aftermarket 200A alternator on my old Dodge van when roving. We have a
> commercial 200A solenoid relay that isolates the radio power system from
> the
> vehicles battery during operation so we don't kill the vehicle battery. We
> have a third marine battery from Walmart that can be switched from parallel
> to series to give us 24v for certain items.
>
> If you have unlimited funds, I would suggest Trojan batteries, probably
> some
> of their 6v units. They seem to be about the best next to the BIG UPS
> batteries used in commercial UPS's that are actually re-buildable. Keeping
> the batteries well maintained is the key to long life. I use a
> microprocessor controlled 40A charger/conditioner when the vehicle is not
> in
> service. The other end of the spectrum is to use the marine batteries
> branded by Walmart. They are about $100 each but there is a Walmart just
> about everywhere and their exchange/warranty isn't too bad. The ones I've
> used have been satisfactory in service.
>
> For roving service, as detailed in other posts, the CCA rating isn't the
> important thing, it's the reserve capacity. The 4DM's I use are rated at
> 15A
> draw for 12 hours each. Our rover idles at just under 20A with everything
> turned on and running. Peaks current during transmit is just under 100A
> (SSB
> and CW). We typically operate 2  1/2 to 3 hours per stop and make 100+ QSOs
> during that time.  We are down to 12.3 volts usually when we move to the
> next stop. If we have little drive time between stops, we augment the
> charge
> with a small generator running my 40A charger.
>
> I'm not sure our system is optimal but it's been working for two years and
> the batteries seem to be as good as they were new. If you are interested to
> see what true sickness is, checkout
> http://directivesystems.com/wp-content/uploads/sites/2/
> 2016/05/Building-the-
> super-rover-Dayton.pptx
> <http://directivesystems.com/wp-content/uploads/sites/2/2016/05/Building-the-%0Asuper-rover-Dayton.pptx>
> which is our rover version 1, we are up to version
> 2.0 which now has pneumatic masts on both front and rear and a new desk
> layout.
>
> 73,
>
> Terry - W8ZN
> K8GP Rover
>
> -----Original Message-----
> From: VHFcontesting [mailto:vhfcontesting-bounces at contesting.com] On
> Behalf
> Of Steve Stahl
> Sent: Thursday, September 14, 2017 9:39 AM
> To: Steve (K1IIG)
> Cc: vhfcontesting at contesting.com
> Subject: Re: [VHFcontesting] BATTERIES
>
> In my current rover setup I'm using 2 group 24 deep cycles that I tie into
> my truck with a rv charging relay.
> Then I use a battery booster (N8XJK )to draw from the deep cycle batteries.
> My main rover radio is a Yaesu 847 which is very voltage sensitive.
> This works great, I never have a issue as far as power goes during a
> contest.
> MURPHY on the other hand. ....
>
> On Sep 14, 2017 6:01 AM, "Steve (K1IIG)" <stephen.tripp at snet.net> wrote:
>
>  Barry,
> FYI, Car batteries are not the best choice for Roving but will work. Car
> batteries are designed to be charged and discharge just like in the car.
> They also do not like to be float (trickle) charged. To get around this
> people use a smart charger that removes the charge when it reaches full
> charge and then kicks in when it drops below a certain level. Car batteries
> are designed for CCA cold cranking and not designed for reserve usage.
> Marine batteries are designed for that type of service and can be float
> charged with no ill affects hence are a better choice for Roving. Running 2
> car batteries in parallel might not be the best choice either. When not
> being charged, they will drain against each other if not disconnected. They
> do make a dual deep cycle marine battery that can perform as a car battery
> and reserve battery. I probably did not explain this clear enough so check
> out this site for a better description. https://marinebatteryguy.com/
>
> Years ago I was told there are only 6 manufacturers of wet (flooded) cell
> batteries, Gould, Exide and a few others. Here is an interesting cut and
> paste I found.
> How many car battery manufacturers are there in the world?
> As of May 1, 2013, there are three major automotive starting flooded
> battery
> manufacturers in the United States. There are four absorbed glass-mat (AGM)
> starting battery manufacturers and there are four flooded deep cycle
> battery/major deep cycle battery manufacturers in the United States.
>
> There are dozens of brands of batteries made to different specs. Interstate
> seems to be one of the most popular car battery.
>
> 73's
> Steve
> K1IIG
>
>
> Interesting battery discussion. Also interesting that the IC-910 seems to
> take significant d.c. power.
> I've recently acquired an Icom IC-9100 and I'm trying to choose the 13.8v
> portable power source. Last weekend in the Sept VHF contest the rig was set
> up for the first time with my SUV, and I discovered that my usual single
> automotive (Sears Diehard) sealed lead-acid battery is insufficient. This
> battery has worked well with an FT-897 and an IC-7100, but the larger power
> drain of the IC-9100 causes the rig to reset itself on xmit.
> Is there a way to calculate how long two car batteries in parallel would
> last?
> I already have a small Honda generator although I don't usually bring it
> along unless I'm using an amp.
> Thanks in advance,
> Barry K7BWH
> Seattle CN87us
>
> -----Original Message-----
> From: VHFcontesting [mailto:vhfcontesting-bounces at contesting.com] On
> Behalf
> Of Alan Larson
> Sent: Wednesday, September 13, 2017 3:42 PM
> To: vhfcontesting at contesting.com
> Subject: Re: [VHFcontesting] The digital modes and the Sept contest
>
> > Hi Alan.  That is useful info re the ic910.  I'm just curious what
> > type of batteries are you using.
> >
> > I've had considerable success running my ic7300, FT736, multiple
> > Icom706MkiiG's, an icom 735 IF radio, 300 watt amps on 50 and 144 MHz,
> > transverter, etc..  from two 12 V 100 AH Agm style batteries.
>
>   Over the years it has varied, but typically I would have 25 - 30 amp
> hours
> of sealed lead-acid batteries in parallel with the starting battery of the
> diesel VW.  Solar would be attempting to hold that up.
>
> > I took another 100 AH battery with a solar panel with me during the
> > June contest and used it to run an inverter that in turn powered the
> > battery chargers for the computers and also powered another charger to
> > top off the two radio batteries.  I had ample power for approx 6 to 8
> > hours of operation including some MSK144 at close to full power on 50
> MHz.
>
>   When operating from a small motor home, I have used 200 AH of battery
> feeding an inverter feeding a switching power supply to run the rig.  In
> the
> more space limited Volkswagen, a small Honda generator has proven to be the
> most convenient option.  (This includes consideration of the difficulty of
> getting all the items inside the Jetta.)
>
>   For low power operation, I would still choose solar if available, but I
> wanted full power from the rigs.
>
>         Alan
> _______________________________________________
>