Fenix CL20 Lantern Field Use Review.

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,433
Location
New England woods.
Fenix CL20 field test review.


I spend a a good amount of time with a light strapped to my head. It gets old fast when in camp so am always on the lookout for lantern options. Also lanterns have some pros to headlamps and flashlights within a group setting be it during blackout conditions or around the campfire. Head lamp courtesy is a term for when people blind each other with their headlamps. As technology increase the output of headlamps and flashlight so does the level of aggravation in some settings. One solution is a lantern. Here are the features of the CL20 as listed by the manufacture.


Features:


Utilizes nine neutral whte LEDs and two red LEDs with an even and smooth beam
White light with four output options
Turbo: 165 Lumens (2 hours and 23 min using AA Ni-MH; 3 hours and 10 min using AA Alkaline; 2 hours using CR123A
High: 100 Lumens (5 hours and 15 min using AA Ni-MH; 4 hours and 9 min using AA Alkaline; 3 hours and 31 min using CR123A
Mid: 50 Lumens (11 hours and 28 min using AA Ni-MH; 9 hours and 8 min using AA Alkaline; 7 hours and 32 min using CR123A
Low: 8 Lumens (71 hours and 40 min using AA Ni-MH; 56 hours and 40 min using AA Alkaline; 46 hours and 50 min using CR123A
Red light with two output options
Regular: 1.5 Lumens (27 hours and 10 min using AA Ni-MH; 24 hours and 15 min using AA Alkaline; 20 hours using CR123A
SOS: 1.5 Lumens
Powered by one CR123A Lithium battery or two AA (Ni-MH, Alkaline) batteries
Built-in magnet for easy attachment
Digitally regulated output - maintains constant brightness
One-button switch for easy and fast operation
Reverse polarity protection guards against improper battery installation
Made of quality plastic and high-transparency material
Waterproof to IPX-6 Standards: Protection from heavy splash and rain


So lets take a look.


It easily fits in my hand.





The UI operates from a single button which is placed in an ideal position for access when hanging.





Can hang from the same loop which turns to open the battery compartment. There are two reasonable strong magnets on both sides. The proper turning diction is shown for access to the batteries.





Magnets don't seem to have any difficulty supporting the lantern.





Open. On a side note I am not recommending Goal zero batteries rather that's what was charged and available at the time. The top or bottom depending on perspective is held in place by a simple lever.





Duel fuel capable however I tend to use this lantern when running 2XAA. Everyone in my bag is on the same diet be it GPS, camera, headlamp or flashlight.





It does feel noticeably lighter with 1XCR123 rather than 2XAA NiMH.





So how does it look compared to another Fenix lantern the CL25R in actual use? Not bad! The CL25R runs 1X18650 or 2XCR123 and is brighter but IMO the CL20 preforms better when hung and the 9 lumen mode is really nice. Both are winners each with their own pros and cons. I normally only pack one depending on the prevailing battery type of everything else. If running a Surefire/Malkoff and Fenix HP12 or Nitecore HC30 then the CL25R gets taken. If I am running the Fenix HL30 and 4/7 mini 2XAA then the CL20 goes.








But then again why pack a lantern at all if solo? On a recent outing I had the following electronics.





Notice the DIY lantern/diffuser which fits on the 2XAA 4/7 mini. I normally try to reduce pack weight whenever possible. I don't always pack a dedicated lantern when solo though do if within a group. However excess gear within my pack must be multi purpose or it doesn't go. This applies to both camping and preparedness aka BOBs etc. Granted a water filter need only be a water filter etc etc etc. That said something like a lantern had better do more than just sit on a log. So what else does this do?


1. Extra battery carrier. Two extra batteries can be robbed to power the GPS or anything else which might be more critical at any given moment. The ability to use CR123 only increases this versatility.


2. Backup flashlight. If only packing the headlamp this roll is important. Here is one area which the CL25R struggles (however it wasn't designed for it) but the CL20 does ok. The CL25R produces too much glare unless a glare shield is field expedited for extended use as a flashlight. The CL20 emits light from a top dome much like a flashlight throws from it's bezel window. Granted it's a pure flood light but actually works just fine as a backup flashlight. Heck even the switch is in a good position for easy access. The hanging loop makes for a nice finger loop.





3. Camp marker. Sometimes it's necessary to forage water and wood at night. A lantern makes for an deal camp marker as the floody glow can be seen far off from any angel though a tree can temporarily block line of sight however unlike a reflector it's not dependent on an external light. Useful for fast camp finds if the headlamp/flashlight should fail or outside their range. Believe it or not people have been turned around from their camp even from a short distance at night if conditions and situations conspire.





4. Goes without saying the CL20 makes for a great lantern. The mode spacing and neutral white tint are very good for my needs. Often most of my headlamp use is within camp. The position of the dome and 9 lumen low output is really about perfect for most camp work. This saves my headlamp from use.








Other features tested:


1. Drop test. I never really need to do an intentional drop test as always drop stuff. This time I forgot to lock the top in place with the lever so the bottom fell. It struck the ground tossing the batteries. No problems!


2. Water test. It's rated for heavy splash/rain. There is an o-ring on the tight fitting lid which worked just fine through multiple storms. No dunk test was done as it's not rated for that but there would be no problem in heavy rain based on my use.


Pros and Cons:


Pros.


1. An fantastic lantern. Everything about it works great in this role.


2. Multi fuel.


3. Makes for an ok backup pure flood flashlight.


4. Not all that heavy at 3.6 oz empty.


5. Nice mode spacing and tint.


6. Red light modes though I don't use them.


7. The magnets are strong. I don't use them in the woods but rather nice around the house.


Cons.


1. A bit expensive. Priced from 30-40 dollars.


2. The low mode might be too high for some people. The CL25R has a 1 lumen low mode which could be preferable in some situations.


3. I worry about the thin plastic the metal lever slides into holding the two parts together. So far it held up but seems like a potential failure point. That said the bottom of the light runs interdependently from the top.


4. A lantern in a solo setting is a luxury item IMHO. When doing a gear shake down to drop weight even with the multi use applications it would be high on my removal list.


Here is a video review of the CL20.





For those who haven't seen my video review of the CL25R as talked a bit about it within this review.





Thanks for looking!
 

ven

Flashaholic
Joined
Oct 17, 2013
Messages
22,533
Location
Manchester UK
Great review, thanks for sharing:) your uses are a little more exciting than mine! I use mine in work.................very handy when you need to light up a close area and need both hands.

Not sure how long i have had it now, maybe around the time it came out to now so coming up to 12m or so, issue free in this time and fed eneloops.

To nit pick, getting the cells out is not too easy, a tap on the palm drops them out though. Also if nothing is tied around the metal hanger on the base, this can be a bit of a pita to get out.
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,433
Location
New England woods.
Thanks for looking!

I agree. The CL25R is much easier to remove the batteries and I trust the twisty cap more than the CL20 lever locking thing.
 

tritan

Newly Enlightened
Joined
Dec 27, 2005
Messages
98
How does this work under a tarp playing cards? I have a streamlight lantern that I take the globe off so I can hang it and have light shining straight down for cards.
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,433
Location
New England woods.
How does this work under a tarp playing cards? I have a streamlight lantern that I take the globe off so I can hang it and have light shining straight down for cards.

Never played cards under a tarp but the light shines down very well. Thanks for looking.
 

Mr. Tone

Flashlight Enthusiast
Joined
Jul 2, 2009
Messages
2,350
Location
Illinois
I have recently lost my CL25R. :banghead: So.............., I ordered three of these from Fenix Store this weekend. One for me, one for my daughter and one for my son. My daughter and I got the olive but my son wanted the blue. There are definitely some cool design features to this light. My CL25R was used often by me next to my bed on moonlight mode the most. I wish the lowest mode on the CL20 was as low as the CL25R. This shape should provide an ideal light for hanging from the center of a tent or attaching to a vehicle hood on the inside, etc.
 

Subterrestrial

Newly Enlightened
Joined
Jul 20, 2016
Messages
187
Location
The Mountains (they were calling....)
Thanks Woods Walker, this review helped me pull the trigger on this lantern. I got the blue one. Plenty of light and a good range of light modes. I like the magnets, just stick it on the fridge in a power failure and you've got plenty of light in the kitchen. The low mode is low enough IMHO. I can't wait to take this thing backpacking!
 

LED_Power_Forums

Newly Enlightened
Joined
Mar 15, 2017
Messages
75
Have an olive version one as well. Generally is a very good lantern with pleasing neutral tint. It is just...that recently I discover the unit whines with high pitch/frequency noise especially at lower mode, making me suspect if the electronic being used is of lower quality than before. The lower the level, the louder the whining noise. I have another cheapie 3xAAA neutral lantern PLD 8506 which behaves exactly the same, just louder. Not sure how long these lanterns can last with them behaving like this? Both of them have pretty good neutral tint though.

Any of the CL20 owners experience this? I mainly use eneloop in mine.
 

ven

Flashaholic
Joined
Oct 17, 2013
Messages
22,533
Location
Manchester UK
My daughter has took over mine, but no driver whine at all on any mode. It is also fed a loop diet, tend to swap out cells every 2-3 days for fresh.
Have you tried it on a single 16340 cell, see if you still get the whine?
Maybe try cleaning contacts up, Q tip/alcohol or alike on the contacts/springs..........just a thought.
 

Subterrestrial

Newly Enlightened
Joined
Jul 20, 2016
Messages
187
Location
The Mountains (they were calling....)
I have the blue version and it has driver whine, but I have to hold it right up to my ear in order to hear it (and I have "dog hearing"). It goes up in frequency as you go higher in modes so it's just the usual, ever pervasive PWM. I'm pretty sure the CL25R doesn't use PWM, but the clones do apparently.

Also, wouldn't a 16340 be way too much voltage?
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,433
Location
New England woods.
True sub, it is cr123 and not rcr123! i thought it supported both................

Yup. Lithium ion isn't supported as Fenix has 16340 listed as "banned". That said I often use NiMH though have packed 1XCR123 when winter camping. I just tested for whine as never hear anything before. I needed to open the case up and stick my ear inside like a sea shell but did hear something. I am sensitive to whine and PWM so it must be very slight for me to have missed it.
 
Last edited:

LED_Power_Forums

Newly Enlightened
Joined
Mar 15, 2017
Messages
75
My daughter has took over mine, but no driver whine at all on any mode. It is also fed a loop diet, tend to swap out cells every 2-3 days for fresh.
Have you tried it on a single 16340 cell, see if you still get the whine?
Maybe try cleaning contacts up, Q tip/alcohol or alike on the contacts/springs..........just a thought.

Well, I don't have any CR123 battery to begin with so can't test using that. About cleaning the contact, will try it soon but I guess won't help much since the contact still looks shiny gold and clean. Might be the component inside which limits the current that's giving out the noise I guess, since the lower the mode, the louder it is. My other cheapie 3xAAA lantern also behave exactly the same, so the lowest mode has the loudest whine. Guess I just got "lucky" with my lanterns huh.

Mine I can hear it pretty clear, that's how I noticed the whine. The cheapie one is even louder and the noise can be a little annoying when holding close. I see you swap the cells every 2-3 days so that means you use it regularly. Mine tends to last weeks so most of the time it is on the standby mode, with the batteries loaded inside. A rather off topic phenomena but might be somehow related: my air-con remote which has quite some age to it, hanged one day. So I thought it was broke and unloaded the batteries. After many days, I re-inserted the batteries and it magically revived! If I left the batteries in it for too long, like few days, it would hang again. So I guess letting batteries sitting in electrical device idle for too long might not be good to the device?

I have the blue version and it has driver whine, but I have to hold it right up to my ear in order to hear it (and I have "dog hearing"). It goes up in frequency as you go higher in modes so it's just the usual, ever pervasive PWM. I'm pretty sure the CL25R doesn't use PWM, but the clones do apparently.

I thought the CL20 does not have PWM in all modes?
 

Subterrestrial

Newly Enlightened
Joined
Jul 20, 2016
Messages
187
Location
The Mountains (they were calling....)
I thought the CL20 does not have PWM in all modes?
I thought so as well, but what else could be causing the whine? Also, the fact that it goes up in pitch with light level makes me suspect it is PWM. As the light gets brighter, the on cycles of the waveform would need to be longer which could be causing the higher pitches.

Anyway, how can we even hear this? Are we dogs? :thinking: I do have some cheapie lanterns as well and the whine is more noticeable from farther away.
 

LED_Power_Forums

Newly Enlightened
Joined
Mar 15, 2017
Messages
75
I thought so as well, but what else could be causing the whine? Also, the fact that it goes up in pitch with light level makes me suspect it is PWM. As the light gets brighter, the on cycles of the waveform would need to be longer which could be causing the higher pitches.

Goes up in pitch in higher mode? Interesting. Never really notice this but what I clearly heard is louder in lower mode. Have to try picking up the noise again in the next light up. Right now my CL20 is unloaded so will try it out if I have the time to load it up.

I can't notice PWM with hand waving method, so not sure about it since I have no equipment to test the presence of PWM. I can notice PWM of the fluoroscent lamp but not on the CL20, so if there is any, maybe it's at high enough frequency which can hardly be detected?

Regarding the source of whine, my guess is either the electronic component used is not of proper quality or lack of heatsink causes the component inside to degrade quicker. Since it is tightly sealed for waterproofness and the whole unit is made of plastic, I see no proper airflow to free the heat from this little snail light. I remember seeing someone open up the CL20 and there is only a piece of white board with nine neutral leds and 2 red leds on it, and no heatsink seen. On higher mode it can heat up quite a considerable amount with the heat trapped inside, which might affect the other components inside. This might be less of a problem if used at extreme cold situation like snowy places but at hotter place like bathroom, prolong use might bring out the whining problem quicker. Above is just my guess so any electronic expert can feel free to correct me if I'm wrong.

Anyway, how can we even hear this? Are we dogs? :thinking: I do have some cheapie lanterns as well and the whine is more noticeable from farther away.

Hey doggy, pick up the bone I throw at you! :D Ok, joking aside, I think the reason we're being able to hear it is not because we have elvolve as a species to be able to tap into the higher frequencies only accesible by other animals naturally, but the electronics used these days have enabled us to hear it. In other words, lower quality, maybe.
 

hiuintahs

Flashlight Enthusiast
Joined
Sep 12, 2006
Messages
1,840
Location
Utah
I thought so as well, but what else could be causing the whine? Also, the fact that it goes up in pitch with light level makes me suspect it is PWM. As the light gets brighter, the on cycles of the waveform would need to be longer which could be causing the higher pitches.........
I think this is probably inductor whine. I doubt that the LED is driven with PWM. Fenix tends to go the route of current controlled drivers. But even a step up (boost) or step down (buck) switching type of power supply for constant current regulation utilizes the technology of pulse width modulation (PWM) of a fixed frequency to regulate a constant load. It's more efficient than a linear method. An inductor is necessary for boost and buck type switching power supply type of circuits and that inductor has to be turned on and off at a certain frequency in order to translate input voltage to a different level at the output. So while there is PWM of the inductor, this in not to be confused with PWM of an LED.

I tend to hear inductor whine on switching power supplies that aren't quite tuned right in respect to how the circuit board is layed out in regards to noise and ground plane or if the stability feedback isn't quite right. It could also be that the inductor used just so happens to emit harmonics due to its physical design at the particular chosen switching frequency. I think there are other variables that could come into play. I wouldn't worry about it as long as the lantern functions properly and the noise doesn't bother anyone. Naturally from a purist standpoint, the driver would have been a little better of a design if there was no audible sound. But that doesn't necessarily mean more reliable.

I own one of these lanterns also and I can only hear the noise when its 3 inches or closer. So it's a very low noise. The pitch (frequency) goes up with higher output and at the highest it must go out of my audible range as I can't hear it then. It doesn't bother me at all since its so faint. I still really like the lantern.
 
Last edited:

LED_Power_Forums

Newly Enlightened
Joined
Mar 15, 2017
Messages
75
I think this is probably inductor whine.

Pretty much nailed on. I am guessing of something like that, whining caused by at least one of the electronic component. I have no electronic knowledge to boot but my initial guess on the electronic component quality portion is something like using a lower cost copper coil with some impurity in the mix instead of 100% pure copper for instance. From your explanation of PWM, if I understand it correctly, there is PWM going on in between the battery and LED in the circuit but the final electricity when reached the LED is constant without PWM, right?

I think more powerful lights have higher tendency of having the whining noise. Small lights like single AAA ones I don't notice any whine in any of them but bigger lights like single AA ones, some of them tend to develop the whining noise after few years. While the CL20 deploying 2xAA, the whine seems to be there even on the first day I obtained it. And the 3xAAA cheapie lantern with 4.5V being fed into it, has even louder whining. Normally no whining noise is noticed when in the max mode, so I kind of suspect the component which is responsible for limiting the current into the LED is the main culprit.

While the lantern is still usable it's reliability still worries me though. I had a sanyo quick charger which was bought 7 years ago went down after it developed the whining noise. Initially there was no whining noise and all was good. Recently it developed whining noise and got louder after each consecutive uses. The last switched on ended with a light popping sound and that's when it met its end.
 

hiuintahs

Flashlight Enthusiast
Joined
Sep 12, 2006
Messages
1,840
Location
Utah
......... if I understand it correctly, there is PWM going on in between the battery and LED in the circuit but the final electricity when reached the LED is constant without PWM, right?

.........I had a sanyo quick charger which was bought 7 years ago went down after it developed the whining noise. Initially there was no whining noise and all was good. Recently it developed whining noise and got louder after each consecutive uses. The last switched on ended with a light popping sound and that's when it met its end.
Yes, you are right, no PWM to the LED. And definitely if the noise changes over time such as your Sanyo charger, something is failing, however, the consistency of the CL20 lantern tells me its just the way its designed, but not necessarily a reliability problem down the road.

So a switching type of power supply (which a good efficient current regulated driver is composed of), usually has a fixed frequency to turn an inductor on and off. Since the frequency is fixed, then pwm or duty cycle of the on-cycle of that fixed frequency is what is used to keep the output steady as the load varies. So this is not PWM to the LED but PWM within the confines of making a switching power supply regulated based on output load. But what you are hearing isn't that PWM either but is the variance of the switching frequency called jitter and causes the inductor whine.

TI has an application note explaining why it happens for those that want to know more.
Understanding jitter in switching power supplies: http://www.ti.com/lit/an/slua747a/slua747a.pdf

"In practice, however, no converter topology or control scheme is capable of producing 100% ideal switching. Such a scheme would require in finite noise margin. Real DC/DC converters always include some variability in the on-times and off-times they produce, regardless of the stability of their control loop. This variability is referred to as jitter."

I've seen situations where the design had a flaw and as such, the on & off of the inductor had jitter, meaning that the duty cycle was varying even though the load was constant. If the jitter frequency is in the audible range you could hear it. Most switching power supply frequencies are way above the audible range and you won't hear it. When you can hear it .....it likely means jitter or inductor whine.

I have purchased many USB adapters both 12v and AC, and I've heard a low faint hum or buzz on some of those of the same model and others of the same model are quiet. (Or lets say the harmonics produced by the jitter frequency are above the hearing threshold). Even the Samsung brand for the Galaxy cell phones. Not all will do it. Some will. When I want one of those inexpensive USB chargers, I buy several, test them all out, and keep the quiet and less noisy ones for myself. I also test the outputs with load and measure the ripple voltage with an oscilloscope. Most will be consistant. Some will be out of the norm. They vary, but for the most part they work.

I've even had a hard time getting the jitter out of some of my own designs. Sometimes I have to give up due to the nature of the combination of all the parts going together, or call it acceptable. Or I will switch to a different topology or switching IC. With the CL20 lantern if you like it, I would not worry about it as long as the whine isn't bothersome. I still think it will be reliable and isn't a function of a failing component. If the noise increases, then I'd get worried, but I think in the case of the CL20, it's just the way its designed.

Sorry, probably too much information :).
 
Last edited:
Top