To BEC or not to BEC...

[Kailee71]

... that is my question! Now, I have been getting some trouble from my 2s receiver pack and am inclined to blame the BEC, as others are reporting trouble with it too. My dad has very kindly built me a cute little 5-pack of NiMH cells, which should have somewhere between 6.2V and 6.7V when flying. Is this out of range for my kit? I'm mainly worried about my GY-401 and 9254, but for my dark-brown see-though no-name servos I got in the set with my CF 550 from flying-hobby.com I can't find any documentation either. My receiver is a JR/Graupner R16Scan (7052)...

I would like to fly without a BEC if people say it's safe, but will probably get a new one otherwise, as the one that came with my 550 goes low on the LED's far too quickly (I get a maximum of 20-30 mins flying out of my 2s lipo before it goes RED) - or is this normal behaviour? I'm dumping the 2s in any case as i don't want to risk my bird to something stupid like saving 20$!

Any thoughts on just hanging everything straight on the 5 cell NiMH?

Many thanks in advance,


Kai.

[mjdee14]

...
, as the one that came with my 550 goes low on the LED's far too quickly (I get a maximum of 20-30 mins flying out of my 2s lipo before it goes RED) - or is this normal behaviour?


Many thanks in advance,


Kai.

20 or 30 minutes seems close to normal to me.....at 6 mins a flight that's 5 -6 flights...depending on what size lipo your using.

i'm using a TP 1320 and usually get 4 -5 flights before I start to see the lights going out....I have never run it down to red and have a spare 2s 1000 mah lipo if needed. I usually run out of main lipos long before I run out of rx juice.

Get another 2s lipo they are cheap .

[Wazzer]

I use an Aplus 1000mah RX pack and get a days flying 5-6 flights no problem still one green showing.

But i always carry the spare batts from my Coax Heli which are 2s 800mah so i have fully charged spares

JB always forget to charge something before he goes flying, good job i got him covered!!

Ben

[istandalone]

running a bec is better (at least in my opinion) because if you have a main battery failure, with a bec you'll still have swash and tail control to auto. with no bec you might have power, you might not depending on the problem. plus you'll get slightly higher run times. i'm going to switch my 450 over to an external bec soon i think.

[Kailee71]

Thanks for your thoughts all,

I would of course always fly with a seperate rx battery, but my question really was whether or not it was safe, volts-wise, to just stick a 6+V pack into my rx and fly with it. I have even heard that some servos like to be pushed a little, in that they are quicker when running on slightly elevated voltages...
Does anyone here fly with a seperate rx pack but without a bec between the pack and the receiver?

Thanks in advance,

Kailee.

[ukgroucho]

The GY401 can cope with 6V but not the 9254... you can use a Trex 600 step down unit (5V output) or other similar device for the rudder servo if you're confident that the cyclic servos can cope. Cannot comment on that Rx.