Hello,

I am currently putting together a 2M Vanquish and I was wondering why it seems people prefer the linear voltage regulators rather than the switching regulators. I have been using the Castle BEC on my .60 sized planes (off the main powerpack) without any issues. In the case of the Vanquish, I intend to use a 2S lipo regulated to 6V to power the radio system.

I am aware that the switching regulator will generate a ripple but I am wondering if it is significant enough to be noticed.

Thanks,

Teo

At the end of the day, for your purposes (running off a 2S lipo) there is very little difference between the two. A switching regulator "should" run a bit cooler than a linear regulator and for a well designed switching reg the ripple is a non-issue.

So it comes down to comparing size, weight and amp rating.

I've always run the Castle 10A switching BEC in my small electric stuff and can't say a bad word about them, but I run linear regs (homebuilt) in my IC F3A ship, 10A for the plane and 5A for the cdi running off the one battery. I also tend to think that if something does go pear shaped with the regulator voltage source (??) that a linear reg is a little more electrically robust but I've got nothing to back that feeling up with.

Oh, a linear reg set to 6V will need a minimum 6.5V input (0.5V overhead) to be able to regulate, I've never tried to figure out the overhead the Castle switching BEC needs?

Thanks for the information. For the linear regulator, I was looking at the Jaccio which is rated at 5 amps. Although labeled as a 6v regulator, I believe its actual running voltage is 5.7 volts. The 2S lithium pack should nominally provide 7.4 volts under load, so I believe that I have adequate overhead. I have several of the 10 amp Castle BECs, so I will have to take a look at the specs to see how much overhead it needs. I suspect that I should be OK. It seems to me that most people are using linear regulators, so maybe I will try the Jaccio. From what I have read, a 5 amp regulator is adequate for pattern specially if using electric power rather than IC (no vibration for the servos to contend with).

Thanks,

Teo

Switching regulators create RF noise and it was enough to degrade receiver performance back in the 1990s. I suspect that is not a problem with modern receivers operating on 2.4 GHz. Linear regulators have fewer components and are very stable and reliable. They are almost indestructible, they can even be shorted out and still survive. One very important feature is their ability to isolate the power sources if operated in parallel as in a redundant battery pack system.

The Jaccio is available at both 5.7 and 6.0 volts as well as 5.1. They only require .2 volts overhead. The 5.7 was selected for 5 cell NiCd packs so they could operate down to 5.9 volts. With 2s LiPo packs down to 7.5 volts there is plenty of overhead so the regulated voltage should be as high as the servos can take. I'm running 6.3 on JR servos. With LiPos there is a potential of overheating if your average current is too high, but that is not a problem in pattern planes with 5 or 6 servos, especially if it is electric powered with low vibration.

Jim O

Jim,

Thank you for the info. I think that I will go ahead and order a linear regulator.

Teo

try powerbox sensor switch. it features double redundancy power and failsafe switch. Hobbyking sells it at $100 only 35 grams

I use the magnetically actuated switches sold by EMCOTEC out of Germany (available in the US from HKM-USA). They make a variety of switches, some regulated, some not, and with different plug types. I use the dual input dual output regulating model. 2x2S (730mAh) lipos in, regulated to 6.0 volts out.

http://shop.rc-electronic.com/e-vend...=6&c=541&p=541

http://www.hkm-models.com/Emcotec.html

I have several of these in use and I love them. Never had an issue. They fail in their current state, but I have never had one fail, even in giant scale vibrating monsters (150cc plane). They are solid state devices. They have no moving parts to fail.