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I'm entering the world of ghz radio technology for the first time and considering the Spektrum SPM SR200 2-Channel DSM Sport Receiver with one of their stick radios. Since they don't come with servos, can anyone confirm that their receivers are compatible with standard Futaba style plugs?

Also, when using Lipo batteries with an ESC that does not have lipo voltage cut-off technology, is it necessary to use a separate cut-off module between the receiver and ESC?

Thanks for the help.

Spektrum receivers are compatable with all standard servos (made within the last 15 years or so anyway). The only problem you may run into is a futaba style plug with the ear, which the ear will need to be cut off. Also beware of cheap high power servos as Spektrum receivers can "brown out," which if happens you'll need to run a capacitor.

You will need an external LiPo cut off if your ESC doesn't have one built in. You can ruin your battery in one run if over discharged. LiPo's should not be discharged below 3.0v per cell (6v for a 2cell lipo). There are all sorts of devices from "cut offs" to "LED's" to "beepers"

R/Cat wrote:Also, when using Lipo batteries with an ESC that does not have lipo voltage cut-off technology, is it necessary to use a separate cut-off module between the receiver and ESC?

This does depend entirely on what you are planning on doing with it.

I run lipos and old ESCs without a cutout with no worries, because I only use them for racing and I take at most 50% out of the lipos in a race. If I was planning on bashing with them with no time limit controlling how long I run I add an alarm as protection, although as I stop as soon as I notice a drop in speed I have never gone low enough to set off the alarm.

terry.sc wrote:

R/Cat wrote:Also, when using Lipo batteries with an ESC that does not have lipo voltage cut-off technology, is it necessary to use a separate cut-off module between the receiver and ESC?

This does depend entirely on what you are planning on doing with it.

I run lipos and old ESCs without a cutout with no worries, because I only use them for racing and I take at most 50% out of the lipos in a race. If I was planning on bashing with them with no time limit controlling how long I run I add an alarm as protection, although as I stop as soon as I notice a drop in speed I have never gone low enough to set off the alarm.

Ah, good to know. In trying to keep my Tamiya Vonats racer as "Tamiya" as possible so I bought a Tamiya TEU302BK ESC for it because it has forward/reverse plus a forward only/brake racing mode. I was planning to run lipo but purchased it before I knew about the lipo cut off requirement. It cost me $60, can handle lipos but doesn't have cut-off capability so I think the least expensive option is to pick up a cut off module for $20-25 rather then spend at least another $40-$50 on a new ESC with lipo cut off built in. The fact that I'll primarily be backyard bashing with an occasional race here and there tells me that's what I should probably do.

Since all my ESC's are old ones with no built-in cut-off, it's nice to just be able to run the lipo until I first notice a decrease in speed/power and then stop because I really don't want to install a cut-off module in every car. What kind of increase in run time can I expect from Lipo with brushed motors and old ESC's compared to NiCd/NiMH?

RC10th wrote:Spektrum receivers are compatable with all standard servos (made within the last 15 years or so anyway). The only problem you may run into is a futaba style plug with the ear, which the ear will need to be cut off. Also beware of cheap high power servos as Spektrum receivers can "brown out," which if happens you'll need to run a capacitor.

You will need an external LiPo cut off if your ESC doesn't have one built in. You can ruin your battery in one run if over discharged. LiPo's should not be discharged below 3.0v per cell (6v for a 2cell lipo). There are all sorts of devices from "cut offs" to "LED's" to "beepers"

Yep, thanks. While closely examining a picture of the spektrum receiver I noticed that there was no slot for the plug "ear" so cutting it off is no big deal. I think I'm going with a separate cut off module as well.