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Old 01-06-2009, 09:52 AM   #511
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The ENTIRE Industry is diluted....

Last edited by John St.Amant; 01-07-2009 at 12:38 PM.
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Old 01-06-2009, 12:39 PM   #512
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Hobby King has boosters back in stock. I have one of these and it's been working fine. I did rewire it to have a switch on the input side and I redid the wire length on the output. Been working like a champ and cheap enough to get a spare or two.

http://www.hobbycity.com/hobbycity/s...idProduct=7884

My Tekin is rather unhappy without the booster also. You'll need some kind of booster or receiver pack to have a reliable personal transponder signal anyway. I would also suspect that some of the systems that "work" are limiting the power some due to radio priority circuits.
I just ordered 4 of these. (being so cheap). I am curious on how long they will last with such a low current of 1.5A as a peak. From my calcs 2A was the min peak for these kind of boosters taking into account digital servos, 2.4ghz receivers, transponders, and the control electronics in a ESC.

I got 4 so If I kill one I can play around with running two in parallel. I think these should be quite light without the heavy shrink wrap an replacing the connectors with something more functional in a 1/12th.
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Old 01-06-2009, 01:14 PM   #513
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I haven't had any issues with the 1 amp booster. It doesn't even get warm during an 8 minute run even when I ran modified (makes the servo pull more). You might need something a little bigger for a 10th or oval car but it seems to be fine in 12th.

Just be careful when you rewire the booster because the caps need to be held down by the shrink tube. I think mine weighs about 25 grams or so with all the wires and a switch.
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Old 01-06-2009, 01:53 PM   #514
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I just wanted to chime in with the difference between 17.5 4 cell and 1c 13.5. They are very similar, and if anything i think the nimh car still feels better, however is much more work to setup and maintain. Here is my basis for comparison: Over the past few weeks i have driven Donny Lia's cars several times during his testing stages. I would say at this point that his lipo car is well dialed in and obviously his 4cell car is good. I have been able to drive both cars back to back, and done the same lap times with both. This past weekend i raced his lipo car, and we were even matched power wise, to the degree that we would go down the straight away within 6 inches of each other. The car i raced weighed 706grams.
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Old 01-06-2009, 02:47 PM   #515
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Originally Posted by Fred_B View Post
I haven't had any issues with the 1 amp booster. It doesn't even get warm during an 8 minute run even when I ran modified (makes the servo pull more). You might need something a little bigger for a 10th or oval car but it seems to be fine in 12th.

Just be careful when you rewire the booster because the caps need to be held down by the shrink tube. I think mine weighs about 25 grams or so with all the wires and a switch.
The Caps? as in capacitor? is being held in place by the shirink wrap? I dont quite follow, but I will see whats what when I get mine in hand in a few days.
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Old 01-06-2009, 03:23 PM   #516
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You'll see what I'm talking about when you get the shrink wrap off. I reshrunk mine and it looks like new.
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Old 01-06-2009, 03:45 PM   #517
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Quote:
Originally Posted by Fred_B View Post
Hobby King has boosters back in stock. I have one of these and it's been working fine. I did rewire it to have a switch on the input side and I redid the wire length on the output. Been working like a champ and cheap enough to get a spare or two.

http://www.hobbycity.com/hobbycity/s...idProduct=7884

My Tekin is rather unhappy without the booster also. You'll need some kind of booster or receiver pack to have a reliable personal transponder signal anyway. I would also suspect that some of the systems that "work" are limiting the power some due to radio priority circuits.
Got any pics of that installed??

DK
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Old 01-07-2009, 12:18 PM   #518
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I would like to see some pix and some wiring diagrams as well.
(lipo and booster and switch)

thanks
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Old 01-07-2009, 12:27 PM   #519
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Back in 1979 or so, when dinosaurs still roamed the earth, we didn't have ESC's or BEC's... in a 6 cell (7.2v) 1/12 scale car, we ran one or two diodes in line from the battery to the receiver to drop the voltage and not fry the receiver or servos. Seemed to work fine. For 4 cell indoor racing, we just took the diodes out of the wiring.

Losi sells a fairly cheap 7.4 LiPO for the 1/36 scale Micro-T that could make a good rx pack, can anyone think of a reason why simply putting a diode or two in line to the receiver wouldn't be a cheap, easy, effective way to drop the voltage and not have to find a regulator? If it worked in '79 it ought to work now... At least until Novak's booster is available...

I know today's digital servos draw more current than the servos did back in '79, but back then we ran two servos... so I don't think current draw from one small digital should much of an issue...
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Old 01-07-2009, 12:34 PM   #520
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I'm just running a 7.4 volt receiver pack direct into my Spektrum receiver. The servo works great, the receiver works great, and the transponder works great. I'll let you know if I see smoke or anything blows up; but right now I'm just going to keep pumping 7.4 volts into it.
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Old 01-07-2009, 12:37 PM   #521
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lol U rock rcterp
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Old 01-07-2009, 03:48 PM   #522
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Originally Posted by rcterp View Post
I'm just running a 7.4 volt receiver pack direct into my Spektrum receiver. The servo works great, the receiver works great, and the transponder works great. I'll let you know if I see smoke or anything blows up; but right now I'm just going to keep pumping 7.4 volts into it.
Which servo are you using? Spektrum has stated that their receiver doesn't care about the voltage on there site. So i'm not worried about that one.

Thanks,
Paul
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Old 01-07-2009, 03:55 PM   #523
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Which servo are you using? Spektrum has stated that their receiver doesn't care about the voltage on there site. So i'm not worried about that one.

Thanks,
Paul

I emailed JR about that and they said simply that my servo (3550) is safe to 6v. You hear of people running it oK, so it really comes down to who you want to believe. I'm to the point of just needing to blow my own stuff up trying things because there seems to be two sides of the fence on everything. Seeing is believing. Good luck finding an answer you want to hear.
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Old 01-07-2009, 04:03 PM   #524
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Well my boosters just shipped from HK... I expect them by next monday or so. to me it seems the safest route to go to not over volt your gear. But to each their own. I think in the end the booster not only will be lighter but remove a major maint headache of needing to charge 2 packs for 1 car.
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Old 01-07-2009, 07:29 PM   #525
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Originally Posted by rcterp View Post
I'm just running a 7.4 volt receiver pack direct into my Spektrum receiver. The servo works great, the receiver works great, and the transponder works great. I'll let you know if I see smoke or anything blows up; but right now I'm just going to keep pumping 7.4 volts into it.
just dont do it with an airtronics/sanwa.... it fries them

my KO is fine at 7.2V

I now run two diodes in line on the positive battery lead from the lipo to drop the voltage
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