R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 08-11-2009, 05:10 AM   #1
Tech Champion
 
Core Creations's Avatar
R/C Tech Elite Subscriber
 
Join Date: Sep 2001
Location: Back in the booth
Posts: 5,749
Trader Rating: 95 (100%+)
Send a message via AIM to Core Creations
Default Is Quantum 1, 2 or 3 with Spektrum sill a problem?

I used to run a QC2 and a Spektrum 3000 Rx...I remember it would drop power to my personal and I had to run a cap in my reciever. Is this still an issue.?..I now have the mini 3500 Rxs.
__________________
Core Creations paint thread

Mini Mafia Kansas Chapter - where the monster minis grow!
Core Creations is offline   Reply With Quote
Old 08-11-2009, 05:35 AM   #2
Tech Elite
 
niznai's Avatar
 
Join Date: Feb 2009
Location: All over the place
Posts: 2,940
Default

I'd be interested to know what the problem you experienced was. I am running a QC3 at the moment with a spektrum DX3 and a SR3500 receiver and didn't have any problems I can identify. I felt a couple of times like the car had lost reception for a fraction of a second but I wasn't sure. Could this be a symptom? Where did you run the capacitor?
__________________
Team Greasy Weasel

The best upgrade to any car is some driver skill.

Last edited by niznai; 08-11-2009 at 06:03 AM.
niznai is offline   Reply With Quote
Old 08-11-2009, 05:45 AM   #3
Tech Addict
 
Skitee's Avatar
 
Join Date: Jul 2005
Location: Johannesburg, South Africa
Posts: 745
Default

Probably in the RX so that the BEC doesn't drop out
__________________
Xray T4 2018 ~ HobbyWing Xerun XR10 Pro ~ Motiv RC 4.5
Xray X12 2018 ~ ORCA Vritra VX3 1S ~ Speedzone 4.5

POWERED BY SPEEDZONE USA
Skitee is offline   Reply With Quote
Old 08-11-2009, 07:15 AM   #4
Tech Addict
 
Jam-ehz's Avatar
 
Join Date: May 2005
Location: Toronto, Canada
Posts: 592
Trader Rating: 6 (100%+)
Send a message via ICQ to Jam-ehz
Default

The QC2 I had cut out with the SR3100, the 3500, and even a regular airtronics rx. A 3300uF cap fixed the issue, but I traded it for a GTX, which has been flawless.

I still use an old QC1 in my Mini, with the SR3100 and JR4750 servo, but I need to use a 10,000uF cap in the Rx for that.. Thankfully there's plenty of room in the back of the chassis!

The issue was very evident when I flicked the steering really quick. The AMB and Rx lights would dim or go out, and then the Rx takes a second to reestablish a connection. Not good when racing!

I'm sure the QC3 has resolved the problem, as it's brand new and there's no excuse to not have a decent BEC current for today's electrics. My Sphere TC works fine with anything.

Quote:
Originally Posted by Core Creations View Post
I used to run a QC2 and a Spektrum 3000 Rx...I remember it would drop power to my personal and I had to run a cap in my reciever. Is this still an issue.?..I now have the mini 3500 Rxs.
__________________
-=≡ Tamiya TA05 TRF415MSX F103R M-03R M-04 M-05 ≡=-
-=≡ CRC Carpet Knife 3.2 OFNA LD3 Pro Fastcats Spektrum ׀ווlı ≡=-
Jam-ehz is offline   Reply With Quote
Old 08-11-2009, 07:19 AM   #5
Tech Champion
 
Core Creations's Avatar
R/C Tech Elite Subscriber
 
Join Date: Sep 2001
Location: Back in the booth
Posts: 5,749
Trader Rating: 95 (100%+)
Send a message via AIM to Core Creations
Default

What the problem was is the Spektrum reciever (at least the 3000) was that it draws more than a typical reciever. And the LRP BEC is lower voltage than most high end escS (I believe 5v) and when you have a high power servo, personal and the Spektrum upon accelleration the voltage will be too low for everyhting to run at once and your personal may not count, or the servo may stop suddenly.
__________________
Core Creations paint thread

Mini Mafia Kansas Chapter - where the monster minis grow!
Core Creations is offline   Reply With Quote
Old 08-11-2009, 07:24 AM   #6
Tech Elite
 
niznai's Avatar
 
Join Date: Feb 2009
Location: All over the place
Posts: 2,940
Default

So the fix was to stick a capacitor in the receiver in one of the unused channel pins between the + and - pins?
__________________
Team Greasy Weasel

The best upgrade to any car is some driver skill.
niznai is offline   Reply With Quote
Old 08-11-2009, 07:34 AM   #7
Tech Champion
 
Core Creations's Avatar
R/C Tech Elite Subscriber
 
Join Date: Sep 2001
Location: Back in the booth
Posts: 5,749
Trader Rating: 95 (100%+)
Send a message via AIM to Core Creations
Default

Yep...I just didn't know if that was still an issue with the newer Spektrum recievers.
Quote:
Originally Posted by niznai View Post
So the fix was to stick a capacitor in the receiver in one of the unused channel pins between the + and - pins?
__________________
Core Creations paint thread

Mini Mafia Kansas Chapter - where the monster minis grow!
Core Creations is offline   Reply With Quote
Old 08-11-2009, 09:27 AM   #8
Tech Addict
 
Jam-ehz's Avatar
 
Join Date: May 2005
Location: Toronto, Canada
Posts: 592
Trader Rating: 6 (100%+)
Send a message via ICQ to Jam-ehz
Default

I think it's more the current drawn from the ESC than the voltage itself.

I'm sure I've read the QC1/2 do 5.5V (which is fine, since the Spek Rx can operate at under 3V) but only at a rate of 1.8A sustained. The Rx on its own likely brings it nearly to the limit, add the AMB and some servo movement and the current drawn is easily too much to sustain without a capacitor, so the voltage drops out.

The GTX and current ESC's all sustain 3.0 to [email protected]

Meanwhile my "crappy" LRP Runner had absolutely no problems running the same equipment.. go figure..
__________________
-=≡ Tamiya TA05 TRF415MSX F103R M-03R M-04 M-05 ≡=-
-=≡ CRC Carpet Knife 3.2 OFNA LD3 Pro Fastcats Spektrum ׀ווlı ≡=-
Jam-ehz is offline   Reply With Quote
Old 08-11-2009, 09:38 AM   #9
Tech Elite
 
niznai's Avatar
 
Join Date: Feb 2009
Location: All over the place
Posts: 2,940
Default

QC 3 BEC does 6V/3.5A
__________________
Team Greasy Weasel

The best upgrade to any car is some driver skill.
niznai is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 09:54 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net