Need some info re. Cox ICON Radio Transmitters

It must be rated for 12 volts. They usually test them way above that, just to see where they "cook off" at. I talked to a Futaba rep at one of the hobby shows and he said they run most of there transmitters up to 17 volts for redline testing.

I run a rechargable Lipo in my Futaba 7c and it's a 11.1 volt, 1c discharge, 2100mah pack. It reads about 11.8 volts when fully charged and just turned on.

I would imagine Cox/Sanwa? would test them to at least 12-13 volts, just to be somewhat sure that the average consumer would follow the guidelines stated in the manual, (of which you don't have).

Once you click the radio on with disposable nicads, those volts stay steady for a bit and then drop pretty fast once they do.

[quote="PV Pilot"
Once you click the radio on with disposable nicads, those volts stay steady for a bit and then drop pretty fast once they do.[/quote]

yes that is due to a high voltage cut off as upose to some cells that just wind down others drop unexpectedly.

Hi Bernie, I bought one of the Icon tx from you and it seems to run fine on ni-cd rechargables. I use a Futaba charger with it.

Thanks everyone.

That is where I made the mistake. Rechargeable batteries are 1.2 and not 1.5 volts, so we are back to the 9.6v charger. The Futaba one fits the jack nicely, as will undoubtedly Hitec and Airtronics.

A customer claims his charger has as TX output of 9.6v and 50 mAh. That does not seem right as it would take 40 hrs to charge the battery back.

What is he (or I) missing here?

Bernie

Time to charge is somewhat dependent on the total milliamps of his pack. Usually tx wall chargers are about 125-250mah slow charge rate (overnight).

PV Pilot wrote:Time to charge is somewhat dependent on the total milliamps of his pack.

True. Most wall warts that ship with transmitters have a sufficiently low charge rate to reduce the chance of toasting the battery. For Nicds, a typical slow charge rate is C/10, or the capacity of the pack (C) divided by 10. If the pack has a capacity of 500 mAh, slow rate is 500/10 or 50 ma. But, charging is not 100% efficient --- I generally figure a charge efficiency of around 70%. If the pack were zeroed out, 500 mAh charged at 50 ma would take 10 hours, but at 70%, the time goes up to a little over 14 hours.

However, packs are seldom zeroed (if they were, they likely would be ruined from cell reversal), so the charge time does effectively come down. Like PV Pilot posted, most warts are rated higher than 50 ma. I just looked a one of my Spektrum warts and it was rated at 110 ma. The 50 ma sounds more like the RX side.

Even if his pack were rated at a 1000 mAh, it should charge in 20 or so hours if fully discharged, but not zeroed.