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-   -   Lithium Polymer batteries for Futaba 9ZAP (http://www.rcuniverse.com/forum/rc-jets-120/3372430-lithium-polymer-batteries-futaba-9zap.html)

mr_matt 09-19-2005 10:29 AM

Lithium Polymer batteries for Futaba 9ZAP
 
Hello,

Does anyone know a source of Tx packs for the 9ZAP? I already have the spare plastic battery cases, I just need the right battery in the right form factor.

THanks!


DrScoles 09-19-2005 10:32 AM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
duralitebatteries.com


Mike

Gordito Volador 09-19-2005 04:04 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Mr. Matt,

I was talking to David Shulman not too long ago and he had mentioned that they (Shulman Aviation) had a lithium pack solution for Tx packs. You may want to check with them.

Regards, Bill

seanreit 09-19-2005 04:32 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt, I've tried them all and have done my own packs, I'm liking this pretty good. More than twice the capacity of a duralite:

http://www.hangtimes.com/


CHeck out their transmitter packs. Capacity is capacity is capacity. Only advantage to LIION over NIMH is that you can go months, pull your transmitter out and fly on LION but NIMH you'll have to charge if you go a long time in between use.

mr_matt 09-19-2005 06:02 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Thanks for the tips.

YIKES....100 bucks for a TX battery??

Anyway the main reason I am looking at lithium batteries is the cell voltage, I would like to run a 3 cell pack and set at 11.1 volts as long as possible, I have studied my TX module schematic, and it should have higher TX power output at higher supply voltage (in other words the supply voltage to the Tx module is not regulated, and the output amplifier should put out more power at higher voltage)

A NiMH would have basically the same voltage as a NiCad is this application (8 cell NiMH vs 3 cell Lithium). The lithium voltage vs discharge curve is very flat, so it will have a better load match over time that trying to fly some sort of 9 cell NiCad.

Thanks for the help.


seanreit 09-19-2005 07:24 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt, I'm told that due to FCC stuff we are limited to 1/2 watt output, can anyone confirm/deny this? Also heard the Graupner 24 is putting out 3/4 watt.

This is the first I'm hearing that increase in voltage is increase in Transmission watts. Very interesting.

Maybe Doug can look into this?

FWIW, I believe our tiny cell phones are 1/4 watt. I know the old bag phones are 3/4 watt, lots of people in the back country, rural NEW Mex etc still use bag phones cause it's all that will give them any converage, but they are paying for it in analog service.

A10FLYR 09-19-2005 07:45 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 

Quote:

ORIGINAL: mr_matt

Thanks for the tips.

YIKES....100 bucks for a TX battery??

Anyway the main reason I am looking at lithium batteries is the cell voltage, I would like to run a 3 cell pack and set at 11.1 volts as long as possible, I have studied my TX module schematic, and it should have higher TX power output at higher supply voltage (in other words the supply voltage to the Tx module is not regulated, and the output amplifier should put out more power at higher voltage)

A NiMH would have basically the same voltage as a NiCad is this application (8 cell NiMH vs 3 cell Lithium). The lithium voltage vs discharge curve is very flat, so it will have a better load match over time that trying to fly some sort of 9 cell NiCad.

Thanks for the help.


Matt, the LiPolys will come off the charger at 12.6 volts when fully charged, drop to 12.4 in a little while and stay flat for a long time. At least that's how they work in our "E" stuff. I don't know why they wouldn't do the same in a TX.

A10FLYR 09-19-2005 07:48 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Sean,
I was told by our freq. co-ordinator that 72 meg was limited to 750 mw. and 27 meg was allowed to go to 5 watts. This was some time ago so I don't know if that is still, (or was) true.

Tom Antlfinger 09-19-2005 07:57 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
You are right on the output Matt......been running LiIons in both my 10 X's for about 2 years........never measured the output directly, but get 75-100 more paces of range check by just swapping out the original NiCad.......I am using the Duralite 1300maH packs......I wired my own in, since when I got mine, they did not have replacement cases for the 10X.....now you can get them either way.......either as a prewrapped 4 cell pack with one dummy cell, or fully installed in a new case......at least that's the way it is for 10X's......

The 3-cell LiIons come off the charger at 12.6v and stay above 12.0 v for about 6 flights.....by that time the OEM pack is down in the mid 10 v range......when I originally did my swap, I talked to one of the service techs at Horizon and he told me the RF modules were not regulated as you noted......he also said 12.6 was O.K.......I think he said the output stage was good for about 15.0 v. max......

Tom


A10FLYR 09-19-2005 08:24 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt, go to watt flyer. they are discussing it there. I don't know how to link to the site or I would post it.

mr_matt 09-19-2005 08:38 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Quote:

ORIGINAL: Tom Antlfinger

......he also said 12.6 was O.K.......I think he said the output stage was good for about 15.0 v. max......

Well I hope the heatsink on the JR tx module is better than the Futaba. Honestly I was a bit surprised at the somewhat archaic looking board in the module compared to the inside of the Tx. I have always been impressed with the Futaba TX design (internal) compared to the JR, but that module looks like a pretty old design.

As for the output, I am not sure what the rules are, I would be worried less about total output (it would go from maybe 500 to less than 700 mW, MAYBE) that I would about spurious emmisions. I am not sure all of these Tx's would stay narrow band if you put the power up that high. Not sure if it is legal either, for me I am running on amatuer frequencies so I can do what I want as long as I stay within the frequency limits.

GManning35 09-19-2005 09:28 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Mr. Matt
I think I will add my 2 cents in here. I too have Futaba 9Z radios. I know that it sounds like a lot of money to pay $100 for a TX pack however I did it at least 3 years ago with Powerflight. Never any problems and when the weather goes south and you can't go flying when you're already charged there is no need to top off the next time you plan to go. I have Ion packs in my planes too and they're ready any time I am to fly. The charge time is very short too, so after flying, once you get home put everything on charge and you're ready to go in no time at all. I have had a plane set for at least 8 weeks and it's still charged.
As for the Hang time hobbies batteries. They are about half the cost and twice the capacity however they loose there charge faster than ni-cads just sitting around. Also I hate to open a can of worms however against my better judgment I purchased 4 packs from Hangtime back in April two for me and one for a friend all for 9z radios I figured they would be OK since they are Sanyo batteries. Three out of the 4 have had problems I contacted Hangtime and got no reply. I have no time to deal with this so I ordered a new pack from Duralite and now both my 9Z radios will be Li-Ion powered as soon as the Duralite pack arrives. One of the Hangtime packs seams to be OK since it was cycled. The second one had a cell quite about 3 min. into the first flight after a full charge while I was flying my helicopter, fortunately I was hovering in front of me and landed without incident. The third cooked during a charge my fault for not having a temp probe on it (My Ions never get even a little warm during chargeing). I would suggest that if you decide to go the Hangtime route charge at 300mAh since the charger can detect a peak easier than at the recommended 150mAh. Charging at the fast charge rate is not worth it since the batteries get too hot too quick. So overall I say spend the $100 you can be ready at any time, recharge way quicker and virtually no loss of charge during the time between flying sessions.

Sorry to more or less put a company down but they had a chance to contact me first since I e-mailed them twice. I am sure many have great luck with there NiMHs. This is just something that's not for me. So far I just love Ion's and Futaba must too since the 14Mz comes Ion powered from the factory.

mr_matt 09-19-2005 09:55 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Hi George,

Thanks for the feedback.

What kind of charger will charge these Duralites? I have all kinds of Orbits (microladder, etc) can they charge one (they have Lithium on the menu)? What about the charge safe circuitry, do you need a special charger to interface to that? A 100 dollar battery is one thing, a 200 dollar charger with a 20 dollar bill of material is another !!

Thanks in advance,


seanreit 09-19-2005 11:52 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt, the charge safe circuitry makes no matter for the charger. Any LION safe charger will work fine. I usually set the rate at 500 mah on my Triton when charging the trans pack. The duralite charger charges at 500mah.

The charge safe circuitry is basically just an overload on volts and maybe amps as well.

Interestingly, the duralite charger has "charge safe circuitry" as well. So many of my LION packs that aren't duralite but are 7.4 volt, I charge them on my duralite pack.

I have temp sensors on my triton chargers that I hook to my batteries, you can set a high temp (I set mine at 20 degrees above ambient). If that temp gets hit, the charger goes into a pause state till the temp comes down. Nice feature.

turbine guy 09-20-2005 12:06 AM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Does the higher TX voltage REALLY equate into a stronger output signal?

I remember reading this on Horizon's website years ago regarding range testing and variables, http://www.horizonhobby.com/Explore/...ID=1079&Page=6

Maybe a good Question for George Stiener to answer.

IF higher voltage is going to increase signal strength -that by itself is good for you and your aircraft but, are you likely to swamp adjacent freq. if slightly out of tune?

This could be more harmful to those that fly while you're up.

Something to consider before we all start increasing our TX voltages.

Jake

Silver182 09-20-2005 12:18 AM

RE: Lithium Polymer batteries for Futaba 9ZAP
 

Quote:

ORIGINAL: mr_matt

Quote:

ORIGINAL: Tom Antlfinger

......he also said 12.6 was O.K.......I think he said the output stage was good for about 15.0 v. max......

Well I hope the heatsink on the JR tx module is better than the Futaba. Honestly I was a bit surprised at the somewhat archaic looking board in the module compared to the inside of the Tx. I have always been impressed with the Futaba TX design (internal) compared to the JR, but that module looks like a pretty old design.

As for the output, I am not sure what the rules are, I would be worried less about total output (it would go from maybe 500 to less than 700 mW, MAYBE) that I would about spurious emmisions. I am not sure all of these Tx's would stay narrow band if you put the power up that high. Not sure if it is legal either, for me I am running on amatuer frequencies so I can do what I want as long as I stay within the frequency limits.
Matt,
72mHz transmitters are limited to 750mW by FCC. I have been told that transmitter output today with newer equipment is less than 450mW because of 3IM and other cost / capacity / run time factors of batteries. I can tell you from experience transmitter output can make or break and otherwise marginal R/F link. In fact just this last weekend we reduced a 50% loss in range turbine powered up range check to less than 20% loss by just changing transmitter modules and nothing else. The radio in question was a JR10X transmitter & module. Same frequency but a major difference in output.

I don't have a way of checking modules / output quickly with my Futaba radios other than careful range checks. For JR's I happen to have an older 10 channel and it has an RF meter rather than a voltmeter! It is surprising what you can learn by just switching modules. Some modules actually show higher output with a couple of stages of antenna collapsed! Other modules just show low output.. and some really peg the meter nicely. Range checks have confirmed what that RF meter shows!

It could be that higher voltage equals higher output in some types of radios. I don't have any lithium packs to try out in my older Futaba 9ZWC or even my newer JR10X. I can tell you that my JR transmitter RF meter doesn't begin to show lower outputs until the voltage is below 9 volts!

I do have one of the new 14MZ that does come with a 7.4 volt lithium pack. I would suspect Futaba is regulating voltage and they have designed the output around the 7.4 volts. It range checks very similar to my 9ZWC and JR10X. Doing a baseline range check, 200 paces is what they all seem to get. My new method is antenna mounted but collapsed to equal 7 inches: One because the range check distance is more manageable 200 paces or 600 feet, more manageable than full antenna and 1/2 mile! Two because all brands of transmitters can then be compared with the one stage or 7 inches of antenna showing! Anyway 200 paces baseline is what my JR's and Futaba averages. Those distances compare directly in proportion to a 9Z fully collapsed inside the case, and a JR 10X antenna removed which in each case average 100 paces or 300 feet baseline best! The (one stage check 7 inches) comes out to be double the distance or 200 paces still manageable by one person!

I have changed my method of range checks now completely too the one stage transmitter antenna (7 inches) no matter what type radio. Baseline / powered up less than 20% loss is OK, more than 20% loss change something... minimum baseline is 150 paces powered up 120 paces...

If you do a very careful range check changing nothing but your transmitter battery pack you should be able to measure a difference if there is one. I can confirm all transmitter modules are not equal!
Lee H. DeMary
AMA 36099


Tom Antlfinger 09-20-2005 12:31 AM

RE: Lithium Polymer batteries for Futaba 9ZAP
 

Quote:

ORIGINAL: mr_matt
I am not sure all of these Tx's would stay narrow band if you put the power up that high. Not sure if it is legal either, for me I am running on amatuer frequencies so I can do what I want as long as I stay within the frequency limits.
Good point Matt.......I never did a spectrum analysis comparing the two packs......I also run on the 53 Mhz band......conceivably could be a problem with narrower channel separation on 72 Mhz.......


Tom

EddieWeeks 09-20-2005 09:50 AM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt

I have done what you are trying and its worked fine for a Profi 4000... I went from a 6 cell 3000mah to
a 7 cell. I drive an RC car with a TV camera all around the hood before and after and range went way up.

There was one problem though.... Because of the higher output when I would place the transmiter near
a large sheet of metal (like the hood of my car or steel table) the radio got stupid. The display would give
voltage reading all over the place. The way it was explaned to me is, because these are base loaded transmiters
as you increase the power output, you need to increase the base (Ground of the battery).

It was not a problem because I did not sit my transmiter on a metal plate while I was flying.

I think its a good idea, let us know how it goes.

Eddie Weeks

GManning35 09-20-2005 07:50 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Matt
Concerning the charging everything seanreit said is right on. Personally I have used a charger from Powerflight also a Triton and now my favorite is the Accu-Cycle Elite, I have not used the Duralite one myself but understand that it's good and safe. I would say that if you already have a Lithium type charger available that you like using it will be fine as long as you can control the settings. If you use the automatic programming on a given charger I would suggest checking it quite often to make sure that for some reason a 3 cell pack doesn't get recognized as a 4 or a 2 as a 3, miss-charging is where all the bad things happen with our batteries.
As for range changing due to power, I haven't done any testing and didn't give it any thought however I fly on both 50 mhz and 72. Normally I'm on 50 Mhz however quite often I use 72 for my little electric 3D planes along with some sport planes. I have never had any problems with overpowering other flyers in any way I have not noticed a gain or loss of range during my normal range test but once again I was not looking for minor differences and didn't notice anything unusual.
Futaba modules for years only came in two types FP-TP and FP-TK with the TK being the better version. I have both and have never noticed a difference in range. I am sure something is improved in the TK but I have never been concerned since I have never had a failure with either. I can tell you this about modules; don't leave your antenna down while your transmitter is on. At least have it up a little, especially if you are working with it for a good amount of time setting up something. I have experienced what happens if you leave it down a long time first hand. There is a good chance you will damage the module and reduce your range substantially. I have all too often seen people doing this and saying it does nothing. If that's so why does the temp of the module go up so much when the antenna is down? I would suspect that is what happened to the JR module from the Silver 182's post but can't say for sure.

GManning35 09-20-2005 07:54 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
One last input I have had my radio with the Li-Ion pack spectrum anayzed and it was fine.

mr_matt 09-20-2005 08:28 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Thanks for the tips, and yes Eddie I have a different kind of ground plane anyway (long story)

Lithium TX batteries worry me less as I would take them out anyway for charging and maybe get one of those urns to burn th...I mean charge them in.

And boy oh boy I cannot emphasize enough not to run the TX without the antenna for very long, having seen the inside of these modules (talking about the 9ZAP, have no idea about any others). The output amplifier transistor is very low end made for CB radios and they are not heatsinked at all.

The gain (the amount the transitor actually amplifies) has a 4 to 1 variation (min to max), so every module can have a much different output.

But I have to say that while Bob and I were evaluating the spread spectrum radio ground range, the Futaba 50 MHz module had the best range we tested BY FAR.

Malcolm Kay 09-21-2005 04:00 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
MATT I CONVERTED MY 9ZAP TO LI-PO USING A THUNDER 3 CELL 11.1 PACK I SIMPLY CUT OF THE CHARGING SOCKET/ PIN PLUG END AND SOLDERED THE LI-PO TO IT FITTING IT IN THE RECESS WITH SPONGE, ITS TOTALLY SECURE AND IN THREE WEEKS I HAVE HAD TEN FLIGHTS WITH THE TRANSMITTER AND IT STILL READING 10.3 TODAY......DEFINATELY THE WAY TO GO MALCOLM KAY, TEAM FUTABA.

seanreit 09-21-2005 04:28 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 
Malcom, the duralite guys are recommending that the "stop fly" voltage is 10.8 on the duralite LIIon transmitter packs. Don't know what that translates to for LIPO and Futaba, but just thought I'd throw it out there as food for thought. I have heard that duralite is way conservative on their "stop fly" voltages. But with as many flights as I get, I can live with the conservative.

Sean

mvigod 09-21-2005 04:34 PM

RE: Lithium Polymer batteries for Futaba 9ZAP
 

Quote:

ORIGINAL: seanreit

Matt, I've tried them all and have done my own packs, I'm liking this pretty good. More than twice the capacity of a duralite:

http://www.hangtimes.com/


CHeck out their transmitter packs. Capacity is capacity is capacity. Only advantage to LIION over NIMH is that you can go months, pull your transmitter out and fly on LION but NIMH you'll have to charge if you go a long time in between use.
I agree with sean. I've used replacement NiMh packs and cartridges from NOBS Batteries ( www.hangtimes.com ) in both my 9Z, 10X and 9C. I got more time out of my 9Z then my buddy did with his Duralite lipo replacement when we compared runtimes. Charging is of course easier with NiMh and the only downside as mentioned above is that you have to top off the NiMh's if you let them site for a long time while lipo's will hold their charge.

On my 9C I have got over 4 1/2 hours out of one charge on the NOBS Nimh pack. I charge it once and use it for one or two weekends before bothering to top it off again depending how much I fly.

Here is a video of how to replace a 9Z pack by NoBS that Steve did for us some time ago. I was trying to convince him to do another one for the 10X which is basically the same so not sure if a 10x specific one is worth it.

http://www.rcuniverse.com/magazine/a...article_id=333


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