Do I need a step-down???

[Whichway]

After a class on familiarising more functions on the DX7, I overheard a couple of the more expereinced fliers talking about the need to have a step down regulator when running a Futaba S9257 (4.8 vdc), via GY401, in conjunction with the Aligns' BL-35X ESC (6 vdc). I am in the process of putting my T-Rex 450SE V2 all together for the 1st time, and would like to have everything as perfect as possible, and don't want to burn anything up!!!! If I do need one, where can I get one ??? The LHS isn't sure!!!!:WOW

[simian]

You definitely need a step down or the servo will probably burn out - expensive if it happens in flight. They are available from www.heliproz.com (http://www.heliproz.com) for $7 - search for part K10381A. Fit between the gyro and the servo.

[Whichway]

Thanks for helping me.:noteworthy It would be real bad if the servo burned in flight. The servo was recommended because of it's speed and torque characteristics, but I guess that the voltage requirement was a slight overlook...thanks also for the part description, because I've looked at some of the more favored online sites but could not find one that dropped the voltage below 5.1 vdc.

[Pinecone]

That's why I prefer the JR DS3400G.

But there is a thread in the Finless area about making your own step down. For about $1.

[Whichway]

Pinecone,
Thanks...I did find an Align voltage dropdown for about $4. I was told at the LHS I visited, that the servo spec of 4.8, and the dropdown spec of 5.1 vdc, was not a big deal at .3 vdc difference. I wasn't really sure at just how sensisitive the servo is/was...and can say that I would not like to replace because I suppllied it with too much power.

[Pinecone]

The 4.8 rating is based on a 4 cell NiCd/NiMH pack. Fully charged they are up around 5.6 volts. So 5.5 or lower is fine.

BTW the actual stepdown is just a diode. You can get a pack of 1N4001 diodes at Rat Shack or an electronics supply and make your own.

[Whichway]

I've been looking at quite a few of finless vids, but had not come across the actual procedure for making the stepdown. Really appreciate the input though. Before you told me that, I was toying with the idea of ripping the heatshrink off the one I purchased, and finding out what they were using. I know that you can also run resistors to drop voltage, but at a higher consumption rate. Do you suppose that an electronics store ( i.e. rat shack, as you said) would have those male/female pins that go to the servo connections at a better price than the LHS?

[Pinecone]

Simple way is to buy a 3" servo extension and cut the middle wire and install the diode. The banded end goes towards the servo.

The lighest way is to just install the diode in the servo wire.

Or you could buy some connectors, pins and a crimper and make your own. www.hansenhobbies.com for everything, or www.servocity.com for connectors and pins. Rat Shack has a crimper that works fine.

[Whichway]

You've been a :clappp help. I must say that you are one " all over the board individual "!!! You've given good, accurate answers and in a pretty decent time. What's more, is that I'm not the only person you've helped...where do you find the time? Thanks again:thumbup:

[Pinecone]

Thanks.

Actually over the last couple of months I have been sick and not going to work. Expcet things to slow down as I get back to work. :)