Thread Tools
Jan 28, 2020, 05:00 PM
Flying R/C since 1964
kallend's Avatar
Quote:
Originally Posted by sabreflyer
Thanks for the replies. Sounds good.
Is it still ok to use fuel tubing to protect the antennas?
I use coffee stirrers.
Latest blog entry: Make your own EDF afterburner
Sign up now
to remove ads between posts
Jan 29, 2020, 02:58 PM
Registered User
JPJI's Avatar
Quote:
Originally Posted by sabreflyer
Thanks for the replies. Sounds good.
Is it still ok to use fuel tubing to protect the antennas?
My favourite antenna tube is to cut down an empty bic pen cartridge. Exactly the right size, and nice and rigid if sticking out the side of the model.
(note: any residual ink left in the cartridge can easily be cleaned out with methylated spirits)

They remind me of the old antenna tubes supplied with Tamiya r/c cars back in the old 27MHz days
Feb 04, 2020, 03:24 PM
Registered User
nhk750's Avatar
Hey Andy, so I am thinking it might be a while before we see the SPM9747 become available due to the Corona virus in China now? It sounds like they are cutting back on shipping and manufacture due to concerns.
Feb 04, 2020, 03:45 PM
AndyKunz's Avatar
That's factory stuff, so I have no idea.

From what I see on the news, it looks like a disaster over there for their economy, though, since that province is so industrial. Imagine shutting down the highways around Detroit or Birmingham or NYC, and then all the fall-out. They've got 50 million people locked down, ten thousands of them sick/dead and more happening all the time! Sadly, I expect it to get worse before it gets better.

Andy
Feb 10, 2020, 12:36 PM
Registered User
Can any one confirm that the spm4651t can be used as a remote for the ar6610t and is it just plug and play or do you have to change any thing...
Feb 10, 2020, 03:33 PM
AndyKunz's Avatar
https://www.rcgroups.com/forums/show...&postcount=220

Make sure they both have the latest code in them, which you can do using the SPMA3065 USB cable and the PC-based Programmer software.

Andy
Feb 10, 2020, 03:41 PM
Registered User
Thanks for that Andy. The spm4651t is not in the registration list yet so can i assume that it will have the latest code in it?
Just checked and the spm4651t has version 2.37...
Last edited by Island Heli; Feb 10, 2020 at 03:59 PM.
Feb 10, 2020, 04:05 PM
AndyKunz's Avatar
Try now to register. We had forgotten to check a box so you could see it.

You should see also that there's a version named "Spektrum™ SPM4651T Version 2.37.0 (December 17, 2019)" available. Your programmer will let you know if that's the right one.

THANK YOU for mentioning this!

Andy
Feb 10, 2020, 05:10 PM
Registered User
And Thank you also....
Have now registered it and downloaded the firmware you mentioned.
Also read up on the thread you linked....
Last edited by Island Heli; Feb 10, 2020 at 05:18 PM.
Feb 26, 2020, 06:40 AM
Registered User
doug14's Avatar
is there any risk of running a li-fe pack and esc power into RX at the same time. ?
at first I was thinking of it as a backup like a bec and was going to pull the red wire from esc plug. but then thought.hey why not both. ? can run servos at 6.6v if that pack fails I still have the 5.5v from esc.
gain a bit more power for servos and less draw from flight pack.
are there any risks doing this ?
thanks
Feb 26, 2020, 06:45 AM
Flying R/C since 1964
kallend's Avatar
Quote:
Originally Posted by doug14
is there any risk of running a li-fe pack and esc power into RX at the same time. ?
at first I was thinking of it as a backup like a bec and was going to pull the red wire from esc plug. but then thought.hey why not both. ? can run servos at 6.6v if that pack fails I still have the 5.5v from esc.
gain a bit more power for servos and less draw from flight pack.
are there any risks doing this ?
thanks
Receiver specs quote a voltage range of "Voltage Range: 3.5-9V"

You will need diodes to prevent the BEC and the LiFe pack from interfering with each other.
Latest blog entry: Make your own EDF afterburner
Feb 26, 2020, 12:38 PM
Registered User
Quote:
Originally Posted by doug14
is there any risk of running a li-fe pack and esc power into RX at the same time. ?
at first I was thinking of it as a backup like a bec and was going to pull the red wire from esc plug. but then thought.hey why not both. ? can run servos at 6.6v if that pack fails I still have the 5.5v from esc.
gain a bit more power for servos and less draw from flight pack.
are there any risks doing this ?
thanks
I wouldn't just plug them in at the same time, the battery will feed into the ESC and probably damage the BEC.
In the heli world we often do this sort of thing, however use a backup guard type of product like this one...
https://www.amainhobbies.com/optipow...rbg002/p676086

It monitors the BEC and switches in the battery if the BEC fails, keeps the battery charged from the BEC as well.
Some ESC's have some protection for this type of condition, others even need the additional BEC guard shown...

Tom
Feb 26, 2020, 02:17 PM
Registered User
Kambalunga's Avatar
I use the dual Schottky diode MBR30H45CT.
Voltage regulators can be destroyed if the output voltage is higher than the input voltage. To achieve redundancy, two diodes are required. Otherwise a short circuit in the battery will also cause a crash.
Feb 26, 2020, 06:27 PM
Registered User
doug14's Avatar
ok good to know.
I figured the specs on all receivers were 6.6v for some reason. I use these li-fe packs on my large scale gas plane and never had an issue.
strange.
I was looking at servo specs and they show a decent increase in oz ft torque from 5.5-6.6 so I was hoping to get a little more power out of servos.

so I should remove the red wire from esc and just use the pack. ?
i was going to test it on one plane first and if i get any kind of issues i wouldn't trust it on a better plane.
Feb 27, 2020, 06:10 AM
Blue Skies
hifinsword's Avatar
Quote:
Originally Posted by doug14
is there any risk of running a li-fe pack and esc power into RX at the same time. ?
at first I was thinking of it as a backup like a bec and was going to pull the red wire from esc plug. but then thought.hey why not both. ? can run servos at 6.6v if that pack fails I still have the 5.5v from esc.
gain a bit more power for servos and less draw from flight pack.
are there any risks doing this ?
thanks
As Kam said, you need to isolate the different power inputs. If you're handy with electronics and soldering, here's A LINK to a DIY circuit using Schottky diodes that should do what you want. Or that Opti-Power system will work. For anything larger than a park flyer I normally use THIS SBEC with dual outputs, and 20A output ($15.65 + shp). It's jumper selectable for 5V/5.5V/6V/7V/9V. You pull the red wire from the ESC throttle wire so there's no conflict from separate power sources.

I have seen posts by pilots using 2 power sources without any isolation. And they vow they work fine. I just don't want to take that chance with my planes and hope they will continue to fly. Best practices say isolate each power source.
Don
Last edited by hifinsword; Feb 27, 2020 at 06:26 AM.


Quick Reply
Message:

Thread Tools