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#248859 Telescopes

Posted by ckent323 on 24 February 2021 - 08:49 PM

I have been designing and building telescopes for spaceborne instruments for 45 years.  I have been involved in amateur astronomy on and off for decades.  

There are a lot of telescopes of various sizes collecting dust in peoples garages because many telescopes are not very portable and are a bit too specialized to use for much else besides stargzing. After the viewing of the panets and the moon and a couple of galaxies wears off they tend to get used rarely due to that lack of versatility and portability.

If you do not aleady have a good pair of 8 x 50 or 10 x 50 binoculars I recommend starting there.  Portability, ease of use and versatility are maximized in that range and they can be hand held (anything with more magification must be supported by a tripod).  Either of these sizes would give sufficeint light gathering capability to do some star gazing as well as be handy for use on a boat, while hiking bird watching, wildlife viewing, etc..

I recommend buying a good quality pair with at least 15mm eye relief (more if you want to wear your glasses while using them).   You will pay over $200 but you will be happier with the preformance than a cheap pair.  Canon and Nikon are good brands,  Steiner and Bosch & Lomb, even the higher priced Bushnells, are good enough.  I see Vortex popping up on a lot of lists as a top pick - I am not familiar with that brand so don't know about the quality.  Do some research on quality and shop around.

For a step up from there my recommendation is to get a decent pair of 15x - 20x binoculars and a sturdy tripod (if it is light enough to take hiking it is probably not sturdy enough) that is at least 72" tall (better if 80 " to use while standing).  High power binoculars are more versitile than a telescope and can also be used for viewing distant landscapes and wildlife, etc.  You can also buy adapters so you can take pictures through your binoculars.

You can buy a decent pair of astronomical binoculars new for under $400 and used for $200 - $300.  Like anything else there is a broad range of prices and quality.  The cheaper models (under $700 models) will probably have plastic parts (particularly for the eye piece focus) and because they are relatively heavy you will need to handle them carefully but the Optics should be good enough.

Check ebay for used Zuhmell, Celestron, Meade, Orion, and Oberwerk to name a few.


If you decide skygazing and astronomy is your thing you can always buy an astronomical telescope later.  You will probably have a better idea of what you want too.

Aperture size and field of view for telescopes are an important consideration depending on what you intend to do. 

There are entire web pages devoted to helping beginners get started in the hobby.  Below are links to a few of the many sites out there.








In all events opinions will, of course, vary.  ;-)



I hope this is helpful,



  • 6

#247400 So, you want to setup a good electrical system in your camper?

Posted by Vic Harder on 01 February 2021 - 03:12 AM

So you have a camper shell… or are wanting to start all over with wiring up your camper?  This guide/thread should help.  Technical explanations and even terms like “current” “voltage” and “watts” are not used unless absolutely necessary.


If you have questions or comments, please post them in this other thread instead of here, to keep this one cleaner and easier to read.


Questions regarding "So, you want to setup a good electrical system in your camper?" - Electrical, Charging, Solar, Batteries and Generators - Wander the West



Charging your camper from the truck?

The wiring that comes with your truck for a trailer connection is too thin to carry enough power back to your camper batteries to do much good.  That includes wiring that your camper installer may have put in when you picked up your brand new camper.  This needs to be upgraded to at least 4AWG wire.  Copper wire is expensive these days!  The wire should also be rated to handle automotive (read: greasy and hot/cold).  I use 2AWG welding cables in my builds.


This wire goes from the engine bay, under the truck and back to the truck’s box or flatbed tray to a heavy duty “Anderson Power Pole” connector.  Be careful when you route the wires/cables to make sure they don’t rub or interfere with anything.  When going through metal surfaces, ensure you protect the cable from any sharp edges.


You need two cables, one for the positive wire, and another for the ground.  Using a “frame” ground is not recommended.  The positive wire leaving the battery has to immediately go to a fuse/breaker to protect the wire (and you) in case it gets shorted somehow.  I use 100A Blue Sea 285 breakers.  Its nice to have a breaker (vs a fuse) that you can use as a “switch” to disable the alternator charging function or to remove power during maintenance work.


You will also want to make a new hole or two in the wooden “floor pack” part of your camper and route the wires into the battery box of the camper.  I used a ½” drill, and sealed it with a urethane caulk.  Butyl rubber tape works well as a sealer too.


Just before these hefty cables connect to your camper batter(ies), you will want to add another 100A breaker to the positive wire.  This way the cable is protected on both ends.  From there a short run from the breaker to the positive battery wire completes the basic circuit.


What this means is that the camper/truck batteries are now linked, unless you trip one of the breakers manually, and the truck will charge the camper battery if it running and the camper will charge the truck battery if you have solar and the sun is shining.   Cool, eh?  (yes, I’m Canadian!)



If you do not want to charge the truck from the camper (via solar for example) and the charging function will only ever flow from truck to camper, then you might want to add a DC-DC charger into the mix.  I say might, because an older truck with a “dumb” alternator will now happily charge your camper batteries.  My truck is a 2006 Chevy 1 ton, and I can saw 90A going over the wires (I have a gauge for that) into the AGM batteries in my first FWC.  That’s lots.. like over 1200W!  That usually ramped down very fast (10 minutes) to more like 40A for the duration of the charging time.


BUT, now that I have LiFePo4 batteries, they have a different reaction to charge current, and will take whatever my alternator can through at them.  I was afraid that my alternator would burn up.  So I added a DC-DC charger to LIMIT the charging current to a nice stable 30A.  I’ve used both the Renogy and Victron brands.  The Victron is smaller, but runs quite hot.  I added a cooling fan to keep it happy.

On the other hand, if you have a truck with a “Smart” alternator (almost all have those now) they tend to “manage” themselves and reduce how much power they put out, in order to reduce the load on the engine, and thus improve fuel economy.  As smart alternator will not charge your camper batteries much at all with the stock trailer plug sized wires, and likely not much more with 2g wire.  In this case, a DC-DC charger will make sure you do get a decent amount (30A) of charge whenever the truck is running.


The DC-DC charger goes between the 100A breaker in the camper and the camper battery.  It will likely not fit into an already full camper battery box, so you need to find a well ventilated spot for it nearby.  The closer the better.


If you want to charge the truck from the camper, then you can’t use the DC-DC charger wired like this.  Instead, you will want to use an Automatic Charge Relay (ACR).  I use the Blue Sea ML-7622.  It is robust enough I could actually start my truck with the camper batteries if necessary.  This relay can sit anywhere in the circuit between the truck and camper, as it automatically senses the presence of enough power on either side of the ACR to connect the two systems together.  Meaning, if the sun is shining on your solar panels, you are charging both the camper and the truck.  Or, if driving, the alternator is also charging both the truck and the camper.


More later ...

  • 6

#243750 Mysterious Metal Monolith Found In Utah

Posted by buckland on 27 November 2020 - 07:16 PM

I hate selfies....it's hard enough to look in the mirror to shave.... what do people do with all the shots of themselves? 

  • 5

#242924 Two week quarantines in CA, OR, WA - no recreation travel

Posted by Ted on 14 November 2020 - 03:35 PM

I have taken a jaundiced view of government scientists ever since they had elementary school kids hide under our desks to 'protect' us from a nuclear blast.


attachicon.gifScreen Shot 2020-08-18 at 10.16.43 PM.png


The difference in the masks shown is the first five are to protect you from breathing something in. The last one is also to protect others from what you breathe out. Most people that catch this flu don't even know it for a week or so, but they are contagious during that time. The mask is to help stop them from spreading it as much as it is to protect you.


I get it, wearing a mask is a PITA. As a cancer patient receiving chemo twice a month, I have a "compromised immune system".   And since my cancer has spread to my lungs, it is sometimes a pain for me to breathe without a mask. But I have no choice but to wear a mask when I go to my appointments because so many others aren't wearing one. And while wearing a mask won't kill you, you not wearing a mask can kill me.

  • 5

#242906 Two week quarantines in CA, OR, WA - no recreation travel

Posted by eyemgh on 13 November 2020 - 11:48 PM

My concern in all this is that the recommendations/mandates simply say face covering/mask is required.


There is no mention of any mask ratings/specifications that provide a suitable level of protection for the wearer to avoid infection or to not spread infection. I find no standard for masks or which masks have been tested and proven effective for the purpose. That information is available for dust/various chemicals or pesticides for agricultural/industrial uses and is typically printed on the package. It is missing on packaging for masks being sold for compliance with face covering requirements. 


This has made me very skeptical of the face covering requirements especially when seeing neck gaiters or bandanas accepted as meeting the face covering requirements. Far too many times, I see people at half-mask covering the mouth but not the nose and that is accepted as complying. 


I use KN95 rated masks without exhalation valves when available and the “TV show surgical masks” when KN95 are in short supply. I suspect that the mask requirement is for show or to keep our stress level high. Oregon was just issued more restrictions to start immediately for individuals but in 5 days for businesses.  Why the delay for businesses? Are they less likely to spread the virus?

The governor did tell us that camping is OK unlike this spring when they closed the campgrounds. Either they are not all that smart or we are not all that smart. YMMV, I guess.

By the way, the quarantine period is 4 weeks in Multnomah county but just 2 weeks in adjacent counties.



There is indeed good data on this. It comes out of Asia from institutions that were primarily measuring pollution, but pivoted their particle counter work to smaller particle sizes. Essentially nearly anything helps some. N95s and most real KN95s block 95% or more. Standard three layer procedure masks block 80%. Single layer cloth...60% give or take. Remember though, that's what's coming IN. The primary purpose of the mask is to reduce the distance of what is being exhaled. If you can reduce the distance the particles travel from 6 feet to 1 foot and watch your distance and time exposure, all is good. There's a reason Japan, a densely populated nation with 126 million people has had fewer cases total than we had yesterday alone. This is not that complicated. 

  • 5

#227083 Blue Ribbon

Posted by teledork on 05 January 2020 - 12:12 AM

Only about 2% of our public land is wilderness where motor vehicles are not allowed. I drive on dirt roads some of the time but I have a hard time supporting a group whose users are inclined to threaten me with things like - oh, death -  when I speak in defense of wilderness. 

  • 5

#223762 Thank You

Posted by Mighty Dodge Ram on 24 October 2019 - 03:34 PM

I just want to say thank you to the WTW owners, admin, moderators, and members for providing a friendly and civil forum. I used to spend more time over on another forum...you know which one...but over the years it has become more difficult to post anything without inviting the wrath and nastiness of someone who might disagree with you. Not everybody, of course, but enough vitriolic responses to make it unpleasant. It just seems as if more and more people feel free to post comments that they would never say to someone in person. Perhaps this mirrors the polarization we see in politics these days?


Anyway, really appreciate the tone, manners, and content of this forum. 👍

  • 5

#211370 New batwing awning

Posted by jimjxsn on 01 February 2019 - 11:47 PM

cvant, I just bought a Batwing and am replicating much of what you did here. I too don’t want to add holes to the camper. Have you made any changes to the design? Also wondering what you came up with for the tightening system at the end. They send what looks like a plastic boat cleat that you would hook to and pull the whole system taught at the end. I’m hesitant to use it and not sure where to mount it anyway. Did you come up with anything for the pop up latch? I’ll try and post pics of what I come up with as mine is being fabbed in steel. Thanks in advance, I know it’s been a while since the last post but there ain’t much out there in terms of a fabbed setup for a 270° awning on our rigs.



Here are some pics of my install, different awning and camper but might give you ideas.  I used 1x2 aluminum for the uprights to clear the roof so that it could be placed higher to clear the camper door.  The rear is solid aluminum bar and the front upright is tube.  Then, 1x aluminum angle for the awning attachment pieces at the top of the bars.














  • 5

#202216 Outside Kitchen, Mark II.

Posted by rando on 25 August 2018 - 09:22 PM

Packed up:





It mounts just like the rest of my under tray tool boxes.   It is also right next to the propane hatch, so it can be run off one of the 10lb tanks.   I use the 1lb bottles on the odd occasion that we have a picnic table so you can just carry the stove over to the table.  

  • 5

#53762 Camping USA State Updates

Posted by DirtyDog on 13 July 2011 - 06:57 PM

More Updates (December 23 2011):

Arizona Campgrounds

Idaho Campgrounds

New Mexico Campgrounds

Latest Updates:

Northern California

Southern California

Utah Campgrounds

Colorado Campgrounds

Nevada Campgrounds

Washington Campgrounds

Some city highlights (since I love this new feature): Boulder Campgrounds Las Vegas Campgrounds Seattle Campgrounds


We have updated all the Oregon campgrounds and entered every Forest Service campground in Oregon. The result 868 campgrounds total. We also changed this page to a clustered map for faster loading and easier viewing:


Also note that the city pages (seen below the state map) now have a map layout:


The hope is that in less than a year all states will look as good as Oregon.
  • 4

#249594 Sure Can

Posted by Wandering Sagebrush on 08 March 2021 - 05:18 AM

I use Tide laundry detergent bottles because they're compact, sit upright for transport, easy to fill, and simple to clean and sanitize.  They're also "free" once I use up the detergent.  I used to carry one to use as a hand wash station and a separate one for the dog when he was still alive.




It’s time for a war story, a genuine war story...  In 1968, as a young Marine Lance Corporal, I found myself stationed at a small Marine airfield near Da Nang, Republic of Vietnam.   Certain perquisites, such as the rationing of distilled spirits, followed rank centric protocols.  Said more plainly, you had to be a Sergeant to purchase or possess booze.  

After pleading with the home front, I received a care package that included a one quart plastic bottle of “dish soap”.  The name lost to time, but probably Ivory.  I soon discovered the contents were indeed not dish soap, but rather some of Mr Daniels finest sipping whisky.   We lived in a tin shack, commonly called a hootch, the inhabitants of which were my hootchmates.  After legally (not really, we stole it) procuring ice from sickbay, the hootchmates and I set about to toast the night, the Corps, and all things good with the smuggled spirits.  Tin cups clinked, cups met lips, and...  we all gagged on soap flavored whiskey.


There is a moral to this story.  Well maybe just a lesson...  soap when ingested  with any liquid really doesn’t enhance the flavor of that fluid.  

My advice...  don’t, just don’t, use a soap container for your water supply or booze without trying it prior to setting out afield.

  • 4

#245060 ISS Sightings

Posted by Happyjax on 22 December 2020 - 02:22 AM

I managed to get this nice moon shot with the ISS :) 8 shots in just under a second :)

Attached Thumbnails

  • ISS 7 shot composite 3 2019 web.jpg

  • 4

#228348 How do you plan trips?

Posted by Wallowa on 01 February 2020 - 05:50 PM

Others will give you better advice than this, but for getting there:


#1  Take more time for the trip than you expect to.  Don't rush to get anywhere; "enjoy the ride".


#2  I avoid frwys and heavy populated areas, bad for the nerves. Again, slow down and soak up the experience.


#3  Plan your overnight stops based on camping sites that meet your criteria.  For us, it is, no traffic, no neighbors and dark nights.  Dispersed camping sites in the boondocks are our first choice.




#1  Do searches online and cross-reference what is said about each location you wish to visit.  How much hype, how much reality. We also have a ton of books covering the areas we are interested in.


#2  Are these locations open and available in your time frame.  Consider weather and optional destinations.


#3  Don't try to "see too much" [a shortcoming of mine..] but rather plan kick-back time and several days at one location exploring.


SW Washington?  Well that means you at some level are exposed to a population glut of hypertensive folks....so plan on taking your favorite libation to decompress once on the road!


All good....we are in Southern Utah and Northern AZ in March...take a look at Tuweep Campground on Grand Canyon rim, remote and permit needed....too many of the areas down there require permits which are often limited and handed out by a lottery of some sort.


Good luck!




Ps...Obvious, but prep your vehicle for the type of terrain you plan to travel in.


PPs...You mentioned "apps'; don't rely on electronics, also have backup maps.   Paper is good!

  • 4

#199744 Building a Thinsulate thermal pack

Posted by Lineman on 16 July 2018 - 02:33 AM

I needed more insulation in my camper for the climate right AC to keep up here in the hot and humid Midwest.  I considered the factory thermal pack, but I question how much it would help in this situation and hesitant to try it because of the price point.  I think Reflectix would be effective, but I don't want the hassle of put up and take down.  I wanted a light weight thermal pack with insulation that could be left up full time and allow my 5k btu AC to cool the camper to a reasonable temperature.


So, I started looking at fabric options at Seattle Fabrics and ordered a bunch of samples.  They stock Thinsulate in three thicknesses, the thickest is 210 gram.  I decided this should work, it seemed to compress really well and even folded over on itself a couple times it compresses down to very little.  With the insulation chosen I needed a facing material, it needs to be very thin and synthetic to keep it from soaking up any condensation we don't get wiped up in the morning.  I found a 1.1 ounce ripstop nylon, also from Seattle Fabrics, that seemed to fit the bill.   All together with the insulation, nylon, velcro and shipping totaled $350, inexpensive enough to gamble a home build on.


Over a week later (I used the really cheap shipping) a surprisingly small box arrived and I got started.  After remeasuring everything I rolled out the Thinsulate and started cutting.  Unfortunately this has to be done on the floor, I don't have anyplace else large enough. 



The thinsulate comes 60" wide so two 26" side panels will be cut from it.




This is the second cut and the remainder, these sections are cut 26" wide and long enough to reach well behind the lift panels and will be cut to the exact length later.  Next comes the facing nylon, it is incredibly thin, nearly see through.  It is rolled out and the insulation laid on top.



 An inch and a half margin is allowed for and the whole thing is folded over itself.




The excess is trimmed off, the edges folded in and pinned every three to four inches.  This nylon is so slick I'm afraid it move all over when it is run through the machine.  The 1.5" velcro is also pinned on.  It is only applied where it is needed.  I would normally not pin velcro on, but I want to make sure I get these really long pieces where they need to go.  Here it is all pinned up and ready to go through the machine.



I ran a stitch across each end and two down the long sides on each edge of the Velcro.  Then it was taken out to the camper and installed in place (I first had to install the loop side of the Velcro on the camper wall since my camper was ordered with out a thermal pack).  With it in position I traced the window locations directly on the nylon with a pencil.  You can barely see the marks in the picture below.



Secure the nylon to the insulation with pins all the way around the opening to keep everything in place, then take a deep breath and hope this plan works, it would be a shame to ruin hundreds of dollars worth of material here.



All the windows came out no problem and even in the right spot!  A really sharp knife helps to cleanly cut the nylon, I tried a box blade, but had cleaner cuts with the polished edge on my pocket knife.  The edges of the window will need to be trimmed out with something.  I cut a 5" wide strip of the nylon, folded it in half and stitched it, turned it right side out and then folded in half again and ironed to form the edging.




Pin this all the way around the opening, overlapping the corners.




There is no need to pin the 1/2" Velcro on here, it can be applied when the stitching is done.  After running it through the sewing machine it looks like this, note there is no Velcro across the bottom edge.




Now we need window flaps.  These are built just like the rest of the walls, start with a piece of insulation large enough to cover the window opening plus the edging, I my case that worked out to 36" x 15", then wrap it in the nylon and pin every 3-4".




Velcro is added on the three required edges when it is stitched.  Then the stitched window is stuck in place on the wall panel.



Secure the bottom edge to the wall panel and run a couple stitches across the bottom and bam a window!




Then then whole thing is hung in the camper again to mark the button hole location on the windows for the bungee loop and to mark the whole thing for length.  I decided to make the over all length long enough to tuck behind the lift panel to the first rivet between the lift panel and the soft wall of the camper.  The insulation puffs up enough to pretty much seal the gap between the wall of the camper and the lift panel, so it should help slow the thermal loss there even without running really far behind the lift panel.


1.75" button holes are then sewn on the window flaps, the dark spot is where I marked the location with a pencil when the pack was hung in the camper.




Don't forget the stopper pin across the button hole when it is ripped.  It would really sting to ruin it now, so close to the finish.




All that's left is to cut the pack to length and finish the ends.  I trimmed the pack down just a little longer than the desired finished length, I just used the width of my yard stick, the rolled the facing material back and trimmed the insulation to the correct length.  This allows enough material to create a finished edge.



Here it is stitched.




The top and bottom seams will have to be repaired where I had to rip them to create the finished edge, and then it is time to install it in the camper!






With the thermal pack installed the roof was lowered and buckled no problem.  I rolled the camper out of the garage and raised the top to test the effectiveness.  Missouri blessed me with a couple of 105 degree test days, if it works in this kind of weather it should work anytime we camp.  I left the camper out in the direct sun for two days with the AC on the whole time and checked the temperature every few hours.  The AC kept the inside 13-15 degrees cooler than outside while the camper was in direct sun, it did better of course with a little shade and shortly after the sunset with the ambient still in the nineties it pulled the temperature inside down to 73.  So far I think it is a success!  I look forward to testing it in much cooler temperatures.

  • 4

#153790 I need more power Scotty!

Posted by Vic Harder on 11 October 2016 - 08:34 AM

I hope this thread will help us gather most of the info out there on powering our campers into one place. 


In short, I hope it will address how much power we need, and how to reliably get it.


To start with, I want to acknowledge the work of others in this space.  Forgive me if I miss a few, and please do point them out:



HandyBobSolar -  http://www.w8ji.com/...ging_system.htm


Hawk Solar Upgrade - LINK

Running heavier wire for solar panels - LINK

Rice Build - LINK

DrJ on DIY Solar/Trimetric - LINK

ACR – improving your battery isolator - LINK

Modeling Small Solar installations – CarlD - LINK


How much power do I need?

The first bit we need to look at is how much power is needed.  DrJ LINK indicates about 60 AH/day is typical for FWC use.  If you want to run the numbers yourself:


This calculator can confirm some of that, although it is designed for home alternative energy use - LINK


I went at this in some detail, reviewing each of the appliances I intend to use, which are:


TruckFridge 130L – 24w/hr, 60w input, 5 A; 53 lbs; Size - H x W x D 29 ½" h x 20 ¼" w x 20 ¾" d  (estimate 14hrs/day at 24w/hr)


Shurflo 4009-101-A32 pump 12vdc @ 3.5A (max) = 42W/hr (estimate 2hr/day)


ProPex 2200 heater – 1.4A = 16.8W/hr (estimate 5hr/day)


LED lights total = 1A  (estimate 6hr/day)

Overhead lights = .8A

(Flood lights = 2.8A)

Porch Light = .2A


Fantastic Fan = 1.5A at full speed (.2A at low) (estimate at 4 hrs/day)


USB chargers (negligible?)

-          Iphone


Inverter (120 v to 12v) (estimate running small one of 50W for 2 hrs day)

-          Camera battery charger

-          MS Surface 3 Pro laptop


Total of 60 AH/day.  That’s exactly what DrJ figured out for himself, and also worst case.  For example, the if the heater needs to run for 5 hrs a day, then it is likely cold out and the fridge won’t be running for 14 hrs, and vice versa, meaning my draw could be as little as 53Ah, assuming no furnace is needed on warm day.


How much battery do I need to support this load?

And you can use this to figure out your battery bank size



This Crown website has lots of good sizing info too: http://american-batt...olar-batteries/


To put it in words, Crown and others suggest no more than 30% of discharge for maximum battery life for Flooded Lead Acid  (FLA) batteries, while 50% is possible with Absorbent Glass Mat (AGM) batteries, but that will reduce the battery life.  Plugging in the numbers to the capacity calculator (LINK), or spelling it out like this for my case:


60 AH * 50% and 2 days =   240 AH.  That means I need at least a 240 AH battery as the smallest I can get away with.  If I want to have 3 days between charges, even at the maximum 50% drain the number is 360 AH.   Hmmm, maybe I need to adjust my expectations.


OK, so let’s go for 2 days between charges, but keep the batteries healthier, allowing only a 40% draw... that yields a need for 300AH of total capacity.  OK, let’s run with that.


Crown’s 6CRV330 model battery looks like a good fit here.  Fit being AH.  Size is another matter... it is 14.6” tall.  I will have to design my battery box to fit that. 


Now here is a really strange thing.  A bigger battery (or a lower load) get you more AH of daily use and a longer life per battery than you might expect.  The relationship is non-linear.  Lowering your AH draw or stuffing in more battery will lead to better than expected battery life.  This is reflected in the warranty on batteries, which is often stated as 2/5 years.  Two years of hard use, or 5 of gentle use.  Draining them 50% every day, or just 30%  every day.


What kind of batteries should I get?

OK, so more battery is better.  What kind?  FLA or AGM? 


Apparently you can tilt the FLA up to 45*.  That would be significant pucker for me, so that isn’t really a limitation.

AGM batteries are spill proof.  You can even mount them sideways. That could open up some interesting mounting options in a FWC.


AGM’s can be charged up to 5x faster than flooded lead acid types. 


AGM’s can also handle vibration, because they were designed for military aircraft and the shaking they go through, so wash board roads should be no problem.


FLA batteries need maintenance.  Lots of it, to stay healthy, whereas AGM’s need none.


Finally, FLA batteries are about 50% of the cost of AGM’s. 


OK, so cost favors FLA; everything else favors AGM - vibration, charge time, zero maintenance.  AGM it is.  How to charge them up?


If you want to learn more about batteries, check out this awesome site - LINK or this one - LINK



How do the batteries want to be charged?  There are right and wrong ways to charge AGM batteries.  Battery capacity and life are critically impacted by how they are charged.  Guys like HandyBob are very passionate about the fact than almost NOBODY does it right, and that almost ALL batteries in campers are chronically under charged.


Let’s not be part of that crowd!


First off, there are 3 different types or stages of charging an AGM battery:


Bulk (when you can dump practically unlimited amps into the battery at a pretty high voltage)

Absorb (when the battery is about 85% full, and it gets harder to “push” the amps into the battery)

Float (when the battery is basically fully charged and you want to keep in there)


Manufacturers list a lot more parameters about their FLA  batteries than they do for their AGM batteries.  I suppose the FLA batteries need more maintenance, so that makes some sense.  So , I had to do a bit of digging for this info:


Rolls/Surrette says the max charge rate, or bulk rate, is c20 * 0.35, but more typically c20 * 0.25 - LINK


What does that mean?  The c20 rate is how many Amps the battery can provide before it is completely dead after 20 hours of use. If you want more on AH ratings, go here - LINK.  The c20 rate is the most commonly quoted one, so my chosen 330 AH battery just happens to have a c20 rate of 330 AH.  Running the numbers, I get 330 * 0.25 = 83 Amps, and 330 * 0.35 = 115 amps.  These are the amps these batteries want to see while charging.  Whoa.... that’s a lot of juice.


More importantly, our AGM batteries have a minimum charging current, that being C20 *0.10 = 33A for my 330 AH Crown batteries - LINK


So, now we know that we don’t really want to draw more than 30% of (c20) AH capacity, but can go to 50% in worst case settings.  And we want to charge at least 10% of C20 (330AH) = 33A, and can go up to 115A during the bulk charge phase. 


How to do this?  A FWC will usually have three options – the truck’s alternator, shore power and Solar.  And we introduce another factor here besides the charging current, namely the VOLTAGE at which the battery is charged.  This is really important stuff.  Read on below, but before getting to charging, let’s look at measuring your batteries STATE of CHARGE (SOC)


How do I know what the SOC is of my batteries?

I think many folks have already sung the praises of the Trimetric 2013 Monitor.  I think the simple answer to this question is get one of these.  Done.  As for why, this POST is very relevant – showing essentially that many folks measure their battery SOC when there is no load on it.  That’s a sure way to kill your batteries.  Apparently you need to measure the battery under load.  The last two pictures on this post are perhaps the most important.  The meter shows the battery at 12.1v when at a 49% SOC – the lowest you should ever take an AGM battery.  Disconnect the load, and it bounces back to 12.32V, or 70% SOC.  If you think you still have 70% left in that battery, you will be majorly disappointed in the battery life/performance you get out of it. 


Even this site that has this handy table is mistakenly calling this a no-load table.  The marine folks above think it should be considered a full load table.


Oye, sometimes this stuff makes my head hurt!


Charging via your truck’s alternator

Since we are looking at alternators first, let’s consider what the manufacturer (Optima 75 AH Yellow Top) of my truck’s starting battery has to say about how it should be charged.  LINK


They say it wants from 13.65 up to 15V (up to 15.6 if you can monitor the battery temp), at unlimited amps for the bulk charge, or 13.8 to 15v via a charger for 10 hours for an absorb charge, and 13.2 to 13.8 for float charge.  The min/max amps for optimal charging (c10 and c35) are 7.7A and 30A.

When your truck is running at more than idle it is outputting its nominal alternator rating.  My truck has a 135A alternator. Thanks to the car audio SPL wars, many higher power alternators are now available, and  I can upgrade that if need to.  These guys make BIG alternators LINK


Assuming my Optima Yellow top starting battery is fully drained, my stereo and headlights are on, the draw would be:

Battery = 30A

Stereo (500w amp plus head unit) = 35A

Low beam 2 x 35w bi-Xenon Headlights = 5A

Misc small lights = (10 x 10w each) = 7A

So I have 77A being taken by the truck, leaving 58A for the camper batteries.


To get better charging rates, I can turn off the stereo and headlights.  Assuming I do that and can get the max charge amps out of my alternator, the other key factor to consider is the voltage at the camper battery.  As we saw for the starting battery, AGM batteries want different voltages depending on where they are in their charge cycle.  Assuming for just a second that the alternator can deliver these, Crown says that this is what you want for a 12 volt system (which includes 2x 6v batteries in series):


Bulk v = 15

Absorb v = 14.52

Float v= 13.5


Note: Trojan lists an alternate value of 14.4v for absorption charge. http://www.trojanbat...ry-maintenance/


Anything less than these voltages and the batteries will not charge properly.  They will work, they will take some charge, but they won’t be at full charge, and will drain faster and ultimately fail completely well before their time. 


So we need to get those volts to the camper battery, which means we really need to consider the voltage drop that arises from the resistance in the cabling/wires between the source of the power (alternator) and the batteries.  Voltage drop depends on the specific length and gauge of the wire, for a given current drawn across it.


So, back to my 330AH batteries.  As we saw, they want between c10 and c35 during the bulk charge phase, at 15V.


OK, so can I even get 15V from my alternator?  I just went out and measured my alternator’s voltage output.  To do that, I measured the battery when the truck was not running (11.5v – whoa, that’s pretty discharged, and that after normal short runs for groceries and such... seems like maybe I need to hook up my trickle charger!).  This low state of charge for the starting battery is great for our testing purposes, as it means the alternator will be in bulk charge mode when I start up the truck.  So, I start it up and Woot!!! I see 15.2V!   Remember that Optima says they can take up to 15.6 for short while during this phase.


Now, what do I need to do to get at least 15V of those volts to my camper batteries, with at least c10 levels of current, as per Crown’s recommendation?



I will be hooking up the wires to my alternator (not the battery posts) and I figure that the distance will be 20’ from there to my camper batteries.  This includes all the short little sections between the breakers, the ACR and such.  I will want less than 0.2v of loss, or around 1% so I get the full 15V at the camper battery.


Let’s see what the stock – as supplied by FWC – wiring will get us.  Using this calculator LINK, and assuming:


10 AWG (stock FWC wire)

15.2 VDC from my alternator

With a SET of wires this size (no frame ground)

20’ away

And 33A (c10) minimum for bulk charging


(pic didn't come through)


It looks like I will get 13.88v at my batteries.  That’s an 8.7% voltage drop, or 1.32v.  That only gets me to slightly above a float charge level, not absorb, never mind bulk level.   Clearly, those folks on this forum who have upgraded their wiring from the truck to camper and gotten better results are on to something.


What if I want to get closer to a c25 level of current for my bulk charge?  That’s 25% of 330AH = 82.5A.  Aside from melting my wires, that would result in a 21.7% voltage drop and only 11.9v getting to the camper batteries.  Ouch.


BTW, use this link to figure out your fuse size for a given AWG, so you don’t melt your wires! - LINK


So, what AWG wire SHOULD I use? You can use this calculator from Blue Sea (Link), although it generalizes the voltage values too much.  I prefer to use the original calculator I linked to and use trial and error with the numbers to figure this out


I figure I should be running 1/0 AWG.  That will get me 15V with 50A:



(pic didn't come through)



Let’s think about the implications of this for a minute. 


First, I’ve seen a few folks here upgrade to 4AWG, which isn’t big enough according to our calculations, and yet it seems to work for them.  Why? 


Well, for one thing, they are using smaller batteries.  220 AH or smaller.  C10 for those batteries is only 22A.  Using the calculator and changing the wire size to 4AWG, I get 14.98V at 22A to the camper batteries.  That’s enough to get us well above “absorb” charge state and good enough for a bulk charge even.   Given enough time, that will charge up your camper batteries.


How much time?  Going back to the Optima website, they recommend 13.8 to 15v for up to 12 hours for a 75AH battery.  For the 220 AH battery we just ran the calculator for, that means 220/75 * 12hrs = 35.2 hours to fully charge that 220AH battery.  Oh, and if your starting battery is low too, then you have to factor that in too = 295/75 * 12 = 47.2 hours!  That’s a lot of driving!  And if you need to charge your battery daily... well, last I checked there are only 24 hours in a day.  Ooops.


Maybe this is why my nice new Optima only read 12.0 v this afternoon when I tested it.  The trickle charger goes on NOW.... stay tuned for results on that.  OK, after charging for 18 hours at 10A and 15v the battery reads 13.0 v this morning.  Much better.  How much better?


According to this graph, at 12v I was at 20% of charge before.  Darn near dead.  Now, at 13 v (my analog meter needs to be replaced!) I am at 100% charge.


A quote from HandyBobSolar’s website might be appropriate here:


“Get the battery manufacturer’s charging specifications and pay strict attention to them.  The charger manufacturers are nearly all not setting their equipment up for the voltage that the battery manufacturers specify.  The difference between 14.4 & 14.8 volts is not 3%.  That difference is nearly 20% of the charging range (12.2 to 14.8 volts).  That 20% makes a huge difference in how full the battery gets before the charger shuts off.  You can eventually get the batteries full by charging at 14.4 volts, but it takes hours, not minutes.  We have related industries that are not talking to each other and the outcome is that the majority of RV’s are running around with weak batteries.”(emphasis added)


In short, without some other charging method, your truck will never keep the camper batteries (or the starter battery for that matter) at full charge.


See this LINK for a good write up about how to check your vehicle battery and alternator.


Another implication – and a quick note about battery isolator/charge relays:

Many folks have noticed that the battery isolator prevents their alternators from charging the camper batteries.  Upgrading the wiring and/or using a BlueSea ACR seems to help.  Why? 


The isolator is designed to protect the truck starting system so you don’t get stranded with a dead starting battery.  It monitors the camper battery, and if it is TOO low, won’t connect to it.  What voltage is that?  12.4v.  So let’s imagine that your camper batteries are actually at 14.5 volts and would benefit from a long absorb charge cycle, and they want 20 amps for this purpose (about right for a 100 to 200 AH battery).  The wire feeding the isolator is the same one running to your batteries, and 20’ long or so.


The ACR will sense that it can charge the camper battery (sense voltage implies no current movement).  So it connects.  Current starts to flow across that FWC stock install 10 AWG wire.  As soon as it does, it incurs voltage drop from trying to stuff all those electrons through that tiny wire.  The voltage it now sees is only 13.7v.  So it disconnects.  After a bit, it notices the batteries are back to 14.5 and connects again... click, click, click.... and no charging is really happening.  Sound familiar?


Bigger wire is the answer.


Shore Power:

Folks, there is only bad new here, as the voltage output cannot be easily adjusted to meet manufacturers requirements.  Even so, a lot of members here have the IOTA DLS-30 with IQ4 as their charger.  There is a lot of discussion about the Iota DLS series and IQ4 on the net.  The unit is frankly no good at all for FLA batteries – see post #32 in this thread: https://www.solarpan...a-charger/page3.


That said, it might work for AGM batteries with the IQ4, which also appears to be conservatively set, with bulk/absorb only 14.8v (should be 15) and float at 14.2 (should be 14.52). 


If you are willing to forgo the automatic features of the IQ4, you can use a trim pot inside the DLS-30 to tweak the output voltages, and use the two separate output voltages to manually do (enabled via the Two-Step Voltage Jack) bulk and float charging.  But you have to be careful, or you will boil your batteries to death. Iota DLS manual here http://www.iotaengin...lib/dlsmanl.pdf  and the IQ4 manual here: http://www.iotaengin.../#/products/iq4


Info on the trim pot in this thread - http://forum.solar-e...r-potentiometer


My understanding is that when you adjust the higher voltage – to say 15v from 14.8, the normal output voltage will also go up .2v, to 13.6.  This would give you a good two stage charger, for bulk and float levels.  I don’t know what happens if you adjust the voltage up to 15v and then plug in the IQ4.  IDEALLY, it would stay at 15 for bulk, and scale the other voltages too.  I will have to try that, or maybe someone who already has a DLS30 and IQ4 wants to try this (at their own risk)?


Conclusions re Alternator and Shore Power

My conclusions about shore power are the same as those reached by HandyBob, who says “Therefore, you can’t expect your converter to charge [your batteries], either.  You are actually lucky to ever get your batteries over 80% full with a converter that is plugged in for several days unless the rig is stored and no electricity is being used.”


Oh, and a generator makes no difference here either.  If you are feeding your batteries through the DLS30/IQ4 you would have to run the generator for several days also. 


There is just no way around it.  You have to get the charge voltage up to 15v to get into that bulk charge state, and then once that is done keep it at absorb for many hours to get the last 15% of charge done before you go to float charging.  Shore power through an IOTA unit won’t do it if you are using your camper while attempting to charge it, it just can’t keep up.  And we don’t have enough hours in a day to drive enough to charge fully via the alternator either.


That said, if I was to camp for two days in the winter in Banff NP, and no charging took place, I could get away with my 330AH setup.  My batteries would be down 38%.  That’s acceptable.  They would get partially charged on the 2 hour drive home from the park, and then the IOTA with IQ4 would likely get them up to a full charge during the week before I headed out again.  Boon docking is another story...



In short, we need properly set up solar when boon docking.  And what does that look like?


How many AH do I need to recover?

You want enough solar power to recharge your batteries to full power after the number of days you decided (above) would be how long you will go between charging.  In my case, that was 2 days, bringing my 330 AH batteries down to 40% to a 60% SOC.  Now, on the third day, the sun is out and I need to recharge my batteries, and provide enough power to supply my daily needs to I don’t continue discharging my batteries.  Basically, I need to have enough power coming from my solar panels to run my daily load with enough left over for the battery charging. 


That’s 60 AH plus 330*40% = 60 + 132 = 192AH.   


Sizing your solar panels

You need to know how many solar hours you have in a day at the location where you are camped.  This map gives you a good idea - LINK.  I myself will often be in zone 5, sometimes in zone 3.  That’s between 4.2 to 5 hours a day, at solstice.  In the winter, that can be up to 50% less! Winter also adds snow cover considerations.  Right now I am not planning to camp in winter, so I’m just going to go there right now.  And to keep it simple I’m going to estimate 4 hours of solar a day for my three season camping.


192AH needed with only 4 solar hours available means I need to generate 194/4 = 48.5A when the sun is shining, worst case.


Best case, my system never gets that loaded down, and I just need 60AH every day to keep up with my consumption = 60/4 = 15A 


I suppose it would make sense to assume that a typical scenario would be to go 1 day without sun, and then have sun to do a recharge.  That means 120/4 = 30A are needed every other day during my available sunlight.


The size of solar panels is usually given in watts.  Watts = volts * amps.  I would use 15v for the voltage number to make sure I get the needed voltage to bulk charge the batteries, so the watts needed are 30*15 = 450.


OK, so I will need two 225w panels.  I think I will mount one on the roof and use another in a portable setup.  And I will want to use 24v panels to keep the size of cables down.  Why?  Well, I understand that the wires to the roof are about 10’ long, and that the stock FWC is something like 12 or 10 AWG, depending on the vintage of the camper.  I think mine has 12AWG.


Let’s say I put 3 of the 100W GrapeSolar panels from HomeDepot on the roof.  I would be trying to feed 16.68A at 18v back to the controller.  Plugging that into the voltage drop calculator (LINK) I get 17.47v, a 2.94% loss.  If I use a 265W Canadian Solar 24v panel, I will be trying to move only 8.66A but at 30.6v to the solar controller.  That yields 30.32v, a 0.92% loss.  Much better.   To get the equivalent efficiency from a 12V panel I would need to upgrade the wiring in my FWC to 6AWG, and that is not easy to do.


It gets even more important when considering the portable panel voltage drops, as the wires are much longer to this panel.  I figure that panel will be 50’ or more away from my camper to catch the sun while I am parked in the shade.  Using the commonly suggested 8 AWG wire over 50’ yields a 5.83% loss with that 12v GrapeSolar panel, and only 1.76% with the 24v panel.


24v seems like a no-brainer to me, except that I can’t use the highly recommended Trimetric 2030 charge controller, and have to get a MPPT type instead.  The cost difference is substantial ($300 or more).


I’ve put together a spreadsheet of my costs for this solar setup, and the number is a bit scary, actually.  So I am hoping someone can point out that I made a mistake in my calculations or something.... ;-)



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#226493 Blue Ribbon

Posted by RicoV on 19 December 2019 - 12:30 AM

To quote the BRC website:   "The BlueRibbon Coalition was born in 1987 shortly after Clark Collins, Founder and first Executive Director, was told by then Idaho Governor John Evans that recreationists were not politically significant and implied that Wilderness was more important than motorized access to public lands.  Clark gathered and worked with other recreationists in a huge undertaking to educate all users of public lands in Idaho just how our resources were not being preserved FOR the public, but rather FROM the public. Thus, we have the seeds of what would ultimately become the BlueRibbon Coalition".
Imho, the BRC doesn't come close to embodying the spirit of what wandering the West is about, so I'll join the others above in declining to lend my support to the organization.  I believe there was/is much truth in what Gov. Evans (allegedly) stated.  Again, my $0.02, let the flames begin, hehe...

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