View Full Version : DX7 Batteries on Hyperion Duo help please...
ualdrivr
04-28-2008, 04:49 PM
Hi guys,
Has anyone used the Hyperion Duo charger to charge the stock DX7 TX/RX batteries? I have the Hobbico JR charging leads and I am trying to figure out the settings for the TX battery which is Ni-Mh AA1500mAh 9.6V and RX 4.8V 1100mAh NiCd 4 Cell.
The Spectrum manual says that the charging current should be at 110mAh and that what the stock charger gives out.
I got the Hyperion setup and it charges on Auto mode because I am not sure what to setup for Normal mode. Should I setup the Charging current at 0.1A or 1.5A for the TX and 1.1A for the RX? The charger in Auto mode does not go higher than 0.20A:arggg:
If anyone has done that please help....:confused:
Thanks. Panos
HELINHAWAII
04-28-2008, 05:06 PM
Set your DUO for NiMh 9.6V 1500mAh. Charge rate should be 1.5A.
I charge mine up that way and it works just fine.
EatMorePizza
07-20-2008, 11:44 PM
Just a thought. You should check out the lipo pack for the dx7. Some helifreakmember here sells them. I got it and I charged it only once so far. Its great not to worry about the tx battery when Im messing around with high capacity lipos.
HELINHAWAII
07-21-2008, 02:18 PM
Might not want to do that...
Cut and pasted directly from the Spektrum website:
Heads Up, Use the right batteries in your Spektrum transmitter for best results
Monday, March 17, 2008
Warning concerning use of non-standard transmitter batteries
Spektrum transmitters are designed to be operated on 9.6 or 4.8 volt Ni-cad or NiMh batteries only. Use of Li-Po or other power devices operating at higher voltage can add heat to the system, possibly overloading the power regulating transistor for reduced output. Despite what aftermarket battery manufacturers might suggest, use of non-standard batteries offers decreased reliability of your Spektrum. Our service department has received failures associated with Li-Po packs.
For increased flight time, please use increased capacity NiMh cells, like the JRPB5011 2500 Sanyo pack. Charge these packs with the JRPC223 9.6 volt 270mAh output charger.
TheBum
07-21-2008, 03:25 PM
I think that concern is overblown. I find NiMH packs to be a nuisance because of their self-discharge tendencies, i.e. they never seem to be charged when you need them. I can fly for several weeks on one charge of my Kong Power TX 2200 mAh pack. If it really concerns you, just insert a couple of series-connected diodes in one of the pack leads to drop the voltage.
If you don't care about your warranty, you can replace your voltage regulator with a Dimension Engineering 3.3V switching regulator and eliminate the potential overheating issue completely. I wish Spektrum/Horizon would use these instead of the linear regulators they use.
EatMorePizza
07-21-2008, 06:29 PM
I think that concern is overblown. I find NiMH packs to be a nuisance because of their self-discharge tendencies, i.e. they never seem to be charged when you need them. I can fly for several weeks on one charge of my Kong Power TX 2200 mAh pack. If it really concerns you, just insert a couple of series-connected diodes in one of the pack leads to drop the voltage.
If you don't care about your warranty, you can replace your voltage regulator with a Dimension Engineering 3.3V switching regulator and eliminate the potential overheating issue completely. I wish Spektrum/Horizon would use these instead of the linear regulators they use.
Resistors you mean:thumbup:
TheBum
07-21-2008, 08:42 PM
Resistors you mean:thumbup:
Nope, diodes. The voltage drop with resistors is dependent on current. The voltage drop with diodes is a fairly constant 0.6-0.7 volts each. Two of them in series will give you a fairly constant 1.2-1.4 volt drop.
HELINHAWAII
07-22-2008, 05:14 AM
I think that concern is overblown.
Just throwing it out there. Not a lot of folks here seem to have a great understanding of electronics. Me, I'm past my warranty period and have the parts to do the mod. Just waiting for a rainy day!
EatMorePizza
07-22-2008, 05:09 PM
Nope, diodes. The voltage drop with resistors is dependent on current. The voltage drop with diodes is a fairly constant 0.6-0.7 volts each. Two of them in series will give you a fairly constant 1.2-1.4 volt drop.
Sorry your right. In electronic classes we werent concerned about the .7 volts lost when were working with higher voltages. We needed it to limit the direction of currant and only worry about the foward biased condition . For this situation its definitly better than resistors.
Cant be to worried. How many people on this forum purchased a heli and left it completely stock. Its a crap shoot, you may encounter problems or you may-not. Ill take my chances. I love not having to recharge that tx battery everytime I fly. But I guess for someone who doesnt want to deal with warrenty issues or soldering new rectifiers on the tx board and popping diodes when over heating solder joints it might be safer to leave it alone.
HELINHAWAII
07-22-2008, 05:55 PM
That was my thought too. Might as well let the warannty serve it's purpose, and it did, before modifying it. I plan to use one of my old lipos when it's no longer suitable for flight duty.
TheBum
07-23-2008, 01:31 PM
Me, I'm past my warranty period and have the parts to do the mod.
I don't see how you could possibly be past your warranty period. The warranty on the DX7 is 3 years and I don't think it has been on the market that long.
HELINHAWAII
07-23-2008, 03:21 PM
Oh really! That's cool!
Do I really need to install a voltage regulator to use a LiPo on a DX7 or can I just charge it, pop it in and fly? I saw this one and just want to take the plunge (http://www.readyheli.com/Kong_Power_2200mAh_TX_Pack_for_Spektrum_JR_p/tx-2200-3.htm)
At the same time, I'd prefer not frying my Tx.
TheBum
08-18-2008, 06:03 PM
I've been running mine with a lipo and without a switching regulator for several months and have had no problems. If you really want to guard against too much heat, use my diode idea, which requires no mods to the TX, just to one of the battery power leads.
I have to change a lead on the Tx even if the battery has the same type of tab? This one looks perfect for my DX7: http://www.helidirect.com/product_info.php?cPath=31_593&products_id=7867
EatMorePizza
08-18-2008, 08:59 PM
I've been running mine with a lipo and without a switching regulator for several months and have had no problems. If you really want to guard against too much heat, use my diode idea, which requires no mods to the TX, just to one of the battery power leads.
Ditto .
Iv'e been running it for a while now. I will never change back. I've charged it ONCE in 5 months. I dont fly often but its nice to know when you pick up your TX its still at 11.5 volts.
TheBum
08-18-2008, 11:33 PM
I have to change a lead on the Tx even if the battery has the same type of tab? This one looks perfect for my DX7: http://www.helidirect.com/product_info.php?cPath=31_593&products_id=7867
No need for any mods with that pack. Just be aware that the extra voltage of the lipo will make the regulator in the DX7 heat up more. The extra heat shouldn't be significant as there are many people who are running these types of packs successfully.