I have a Hitec Laser 4, and when I charge the TX battery the LED shows a green light indicating
100% charge.

The problem is when I hook the TX into an ESV to double check, I get a reading of .3v
way down in the red.

The model range checks ok at about 50'.

Is it time for a new battery,or is the radio in need of repair?

I just took this gear out of a spad plane, and I was never able to fly the plane, it would take off and get to about 30' altitude and then just take a hard dive for the ground.

All the time I thought it was something that I had done wrong during the building of the spad, but now I'm thinking that it was the TX all the time. I finally gave up on the plane and was putting the gear into another project when I discovered this.
The only reason I did was because I just got a new ESV in the mail from tower, and I was checking all of my batteries.
Before that all I had to go on was the led lights on the TX.

I bought the TX from a guy here on RCU did I get ripped off?

Anyone with a thought on this situation?

The transmitter has a diode in the charge circuit. You can't get a reliable ESV rading through the charge jack. (you also can't do a good fast charge with a peak detect charge through that jack.)

If you want to get an ESV reading on the TX... pull the battery out of the TX. Use the RX cord. The black wire on the battery is the same as the black wire to the ESV (or the quick charger) the RX cord should fit the TX battery (but use the TX jacks on the ESV and charger...)

Never fast-charge a TX battery in the TX. the battery can't get cooling airflow and culd overheat. This can vent the battery or explode it. Either ruins the battery and can ruin the TX.

I have no idea why they don't just give you two RX cords instead of an RX and TX cord with the leads package... you essentially never will use that TX cord for the ESV or the quick charger. [&:]

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Your experience with the SPAD... you were climbing too fast for the airplane... it stalled dropped the nose and never got back enough airspeed to fly before it hit the ground.

Your balsa/ply trainer can do the exact same thing.

Fred, I looked at the TX battery connectors for all of my radios and none of them would plug into the RX leads. They are a totally different style of connector.

You are right half of the charge leads that I bought are useless.
I cant charge my TX batteries at the field, or even check them with the ESV.

I wish I would have known this before
Now what do I do?

Did you PULL the TX battery comletely out of the TX? (on that model can you access the plug on the battery pack's wires inside the TX case? There's a couple of Futabas that you can't [&:] I don't know HiTech well enough... but they are usually Futaba clones.)

What you should do is... trust th LED's on the TX. The HiTech led's are pretty accurate about battery status.

You almost never need to field charge a TX battery. Just when you forget and leave the thing on all night when you were going to fly in the morning.[&:] You can get 2 to 3 hours operation from a 600 mah TX pack in a 4 ch radio. (that's about all the flying you'll do in 6 to 8 hours at the field if there's only 2 or 3 others there with you and no frequency conflict.)

I talked to a guy at the field yesterday and he told me that you can field charge a TX battery with the TX charge leads through the plug in on the TX.

He said to just take the battery cover off and take the battery out leaving it hooked into the TX and charge it through the plug in. He also said that you just cant cycle a battery through the TX plug in.

Any truth to this? I am getting confused.

The diode in the charge circuit has the potential to confuse the peak detecting chargers.

You can get the field charger to put power back into the battery, however if the peak detection does not work because of the diode... you can damage the battery.

The diode can make the peak detection circuit think the battery has appx 1.2 v less in it than what it really has... or it can prevent the charger form detecting anything about the voltage. (depending on the peak detection circuit design.)

For this reason, it is advisable to not have that diode in the fast-charge circuit. That is why I say...pull the battery out and charge it completely disconnected from the TX when fast charging.

I always prefer to fail on the side of telling you something that will improve the probability that you will not damage your equipment, rather than give any unnecessary risk, even if it might be small. Especially when it is so easy to avoid the potential problem.

Fred, thank you for the help.
I was just getting mixed advise on this subject.
I agree with you that very few people will fly out a fully charged TX in one day.

For me I will just charge it on the wall the night before.

The only reason this came up is my TX battery was dead and I needed it to set up some servos in my newest plane. I wanted to do it quick so I could get on with my project.
Not something I would do on a regular basis.

Thanks again

By the way, the new Futaba plugs suck. They're set up so that you have to remove the back of the transmitter to access the plug, and it's different than any other connector out there. [:@]

You can easily make a connector out of a standard connector (the side with the pins) by simply breaking off the outer housing. I'll be making up some adapters for my transmitter packs so that I can remove the pack without opening the Tx case.
Dennis-

Or... you can clip the battery's wires, clip a servo extension and solder in a plug set that works.

I do this to my Futaba radios that have the battery plug buried inside where you have to pull the entire back off the case to get at the plug. Its easy to do... and hard to do wrong if you have ANY soldering skill.

EveryTX I own has the same style plug on the battery pack.

If you WANT... you can do this connection with the male-female plugs of the servo cord reversed... making it impossible to plug an RX pack into the TX... (and making it necessary to make a custom charger cable... again)