Pa-18cub150

I got a chance to range check the Hitec optima 7 and eclipse 7 setup tonight . I could only get 35 feet away before I lost signal. The instructions say I should be able to get 100 feet away in power down mode.
Can any one see any thing I may be doing wrong in my set up?

Pa-18cub150

tx

speedracerntrixie

My Feedback: (29)

I suspect it may have something to do with the antenna close to and running the same direction as your rudder cables.

JohnBuckner

My Feedback: (1)

If your Optima 7 Receiver is updated to at least ver 2.02(0) and your module is updated to at least ver 2.01(0) then perhaps its time to send the three components in to be checked out. This includes the Eclipse, the module and the rx.

John

Pa-18cub150

Unfortunately I don’t have access to a hpp-22 pc interface. So I haven’t had a chance to update the TX or RX firmware.

I have the afternoon off today and it is suppose to be nice. I was looking forward to a test flight. Guess I just as well work late. ( bummer [&o] )

speedracerntrixie

My Feedback: (29)

I suspect it may have something to do with the antenna close to and running the same direction as your rudder cables.

JohnBuckner

My Feedback: (1)

It is strongly suggest by Hitec that all Optima Receivers, 2.4 Spectra Module and if you are using the Aurora it also should be updated.

I am only an individual but will not attempt to fly any of mine that have not been updated period. Now I have seven six channel receivers that are not current and I currently am getting them all ready to return for updating. I have many others but all those are seven's and up and update them as it comes time to fly them a few at a time with my HPP-22.

I recently got in six more Receivers and its interesting that there is a sticker on the box's that indicates these newest are the latest update and gives the actual update code so you can fly with confidence without updating.

I consider having the ability to update ourselves a real and viable asset to using this 2.4 technology and definately do not consider this a problem its a hugh asset. I know Futaba has updating ablity also for certain of their setups also.

There is a high population of Hitec systems at our field and in some cases the HPP-22's have been shared but at thirty bucks or so I definately want my own and am confident in continued support in update by Hitec.

Bottom line for me is I not only will not fly any of my own systems that have not been updated but also will not fly any of my students stuff either teaching or just testing that is not updated, period.

Sorry I know you did not want to hear that but it is my opinion.

John

Pa-18cub150

Thanks John,
I value the advice I get hear on RCU. If it weren’t for the support I’ve gotten hear I think I would have only lasted in the hobby about 6 months .

I broke down ordered the Pc. Interface this evening.
My next step is moving the antenna to a vertical location and removing TX stand.
I hope I dint have to send this things in!

speedracerntrixie

My Feedback: (29)

You want the antenna to be horizontal just keep it away from anything metal

Pa-18cub150

I got the HPP-22 and updated the TX Module tonight. I am also going to pull the stand off tonight. Hopefully I can get the RX updated in the next day or two And do another range check

Pa-18cub150

This is where I am at.

Updated the receiver and the module.

Removed transmitter stand.

routed antenna out the top away from every thing.

Results :

Range increased from 35 feet to 65 fee in the power down mode still 35 feet short.

Suggestions ?

speedracerntrixie

My Feedback: (29)

Is the antenna horizontal or vertical? It should be horizontal. Here is a pic of my setup. Post more of yours and I can give more ideas. Just had another thought, I get 200 ft with the pictured setup. You may want to pop open the case and make sure the antenna is plugged in correctly. The connector is quite small and there is no real strain relief. Not sure but is that your RX battery right next to the RX? If so you may want to seperate them a few inches and try again.

opjose

Also remember that the range check function is for use out at your field, not in a residential area where you are VERY likely to get signal noise from WiFi and other devices.

Even though 2.4's are said to be immune to interference, that does not mean something else that is chatting on the same frequency range, cannot lower reception range due to noise being generated.

speedracerntrixie

My Feedback: (29)

He will get the same range regardless of where he is. 2.4 is immune to nothing but the signal hopping keeps the system on a clean signal at all times. If this was a 72 MHZ system I would agree with you. This is a shot of where I did my range check. I am standing where the model was and I made it to the other side of the black car and still had good connection. Lots of signal reflection in that situation but todays equipment does a great job of filtering out the weak signals.

JohnBuckner

My Feedback: (1)

OK PA-18, By the way I used to own a J3-C85 lots of wonderful memories. It seems to me that you have reached the point that there really are only two choices and that is to either return the complete package for a check out or installing in a beater and flying.

Now before I get roasted for saying that lets examine another simple form of range check and one I used on only one airplane and this was an important one to me where I had converted a forty five year old Orbit Tx to the Hitec 2.4 system.

That range check was simply a full power check, The power down mode for range checks to me seems to be quite varible and not an exact science. Now I ain,t no scientist or brain surgeon but it was a simple matter to find a nice straight section of highway (in my case it was good old Route 66) and to plop my butt down in the wheelchair on the side of the road with the airplane and a cardboard sign that said 'will fly for food'. Then my buddy proceeded down the road with a new fangled cell phone thingie all the while driving and wiggling sticks. Man, talk about multi tasking. Well guess what when I could no longer see which way that big old pickup truck was heading I figured that was just fine.

Now confession time, I am in a wheel chair and as you can imagine that is not condusive to range checks that are very far away especially in the dirt. I seldom do range checks and go much beyond fifty feet or so in the power down mode. This has netted me with just over fifty (now) Hitec rx's installed and checked (All Optima 7's except seven 6's and one 9) zero problems in the air.

What Oppose mentioned of course could be some issue with your check i.e. the location of your range check but the vertical/horizontal orientation of the boda or the proximity to the battery I doubt are really problems as I have violated those considerations many times especially on the small ships where packaging is so much more difficult. What I have always done however is to observe keeping that boda as far from the engine as possible.

So if you like do a full power check, just return it or fly it in a beater Perhaps all three.

John

opjose

Not true.


It "keeps" hopping within a rather narrow range of frequencies, that often get swamped by other 2.4gHz devices, especially in residential areas.

I've seen this happen with these particular systems when both multiple WiFi access points are fairly close by and things like Microwaves are turned on.

The other devices swamp the entire spectrum that 2.4 devices use.

Don't assume that "hopping" solves all of the problems.

At normal flying sites the risk of this happening is MUCH MUCH lower because you are not as close in to the emitters.

speedracerntrixie

My Feedback: (29)

There are over a million frequency combinations that out equipment can lock onto. Not exactly a small spectrum. I would love to know where you are getting your information. To interfere with our systems at all a signal has to have the same frequency, encoding and power level! That just really dosent happen in the real world. The bodas do have to be horizontal for full range. That way they are most exposed to the signal. Imagine running water in a rain gutter being the signal now position a slender object into the water lengthwise with the direction of the water. Not much exposure. Now turn it sideways, much more exposure. Now the battery issue, most batteries emit a low frequency electro magnetic field. Having it that close the the RX is a bad idea. See the way the servo wires are twisted on the Hitec digital servos? Its because of this field and twisting the pos and neg wires reduces it's effect. When I worked for Lockheed, anything we built with DC current had twisted wires and there was even a spec on how many twists per inch per wire gauge.

Jose, please offer expainations on your differing opinions as I have always done. Your findings don't really add up to me. Then again I have 15 years in RF experience and currently work at a company called Randtron Antenna Systems. I suggest you look it up.

Pa-18cub150

Ordered another optima 7 tonight . maybe I can figure out what component is bad

eddieC

My Feedback: (2)

Not sure why you have a bad range check, but I've found even 2.4 doesn't like being near servo or battery wires. Also, don't put the rcvr antenna laterally (pointing at a wingtip. Best to have it oriented in such a way it's pointed directly at the transmitter as seldom as possible, same with the transmitter antenna. Avoids the null point.

opjose

Have you looked at the frequency range allocated to 2.4gHz band that we utilize?

There are not "over a million frequency combinations", rather there is a rather narrow narrow BAND of frequencies from 24.05mhz through 24.6mhz.

The receivers can lock onto thin subdivisions within that range giving us hundreds ( not millions ) of "slots" within that band.

But any wide band transmission can swamp the entire range.

In the vicinity of towers, etc... that is exactly what happens, and in spite of your 2.4gHz FHSS radio, you have problems.


Thanks I did.... and experienced it directly too.


"2.4GHz radio systems are rapidly replacing the older narrow-band systems that we've been using for many decades.

The advantages of 2.4GHz are manifold and include elimination of the "shootdown" problem and (in theory) a reduction in interference.

However, the 2.4GHz band is often filled with the transmissions of many different devices, all competing for valuable space and each trying to make its own signal heard above the noise.

In most cases, good 2.4GHz RC equipment can cope with the signals created by cordless phones, microwave ovens, WiFi, bluetooth and even video transmitters but, at some locations there are occasions when the amount of noise is simply too much for any RC system to cope. That's why a self-contained portable spectrum analyzer (SA) is such a useful part of any club or modeler's field equipment.

With such a unit, you can keep an eagle-eye on the noise levels at places where you fly and even log that data over an extended period.

If a model on 2.4GHz crashes or experiences lockouts, you can quickly check to see if there was any interfering signal present at the time. At last it becomes possible to determine the real cause of those unexplained crashes. "

http://www.rcmodelreviews.com/spectr...zeroffer.shtml

speedracerntrixie

My Feedback: (29)

I emailed the link to this thread to one of our microwave eng. here at work. He replied thanking me for the laugh and to remind me that the break room complete with 2 microwave ovens is located in the same building where we test all our antennas.


With that said, I'm going to let this one die before anyone else gets his feelings hurt, I have given solid advise to the OP and his range issue and that was my intent.

opjose

Hmmm.... Randtron Antenna Systems tests antennas with Microwave devices not factored out of the tests... checked and noted....

overbored77

My Feedback: (11)

I have my 5 different optima 7's with the antenna mounted in all different configurations. None of them have any interference or range issues.
I am using the spectra module in my 9C and have been thrilled with the performance. I am ordering the HPP-22 as JohnBuckner recommended.
I recently used a friends Aurora9 a few weeks ago, I will be ordering one of those also (that will have to wait for TAX season).

speedracerntrixie

My Feedback: (29)

Chris, I have used my A9 in unlimited sailplane, Pattern, IMAC and pylon. In all aircraft it has been bullitproof. I got the HPP-22 and went through the upgrades, very easy to do. Before this I was a JR user of 25 years.

overbored77

My Feedback: (11)

I am 25 year user of Futaba, started with my cars and boats, and when I got into planes I bought Futaba, I was looking at the 10c 2.4 but for that price
I could buy 2 A9's, I liked the feel and for the price it just can't be beat. plus I have 6 hitec optima 7's i love the 3 pack deal. Probably going to go for a
100cc plane this year, guess I will have to get an optima 9 for it