TommyWatson

My Feedback: (1)

I have posted this in the Futaba Manufactuers forum but I would like to get some input from 9ZAP W2 users.

"I would like to know what is the expected range for a 9ZAP W2 TX and 149DP RX. I tried mine today and could only get about 25 paces with the TX antenna retracted. The model was tail on to me and the engine (48cc gas) was not running and the ignition was OFF. I noticed the range improved (doubled) with one section of the TX antenna extended.
What is normal I am on 36.530 Mhz (Australia)

I have tried the RX antenna outside the model up to the fin with no diference. I have tried side on as well as end on. still the same.

I get over 1000 feet with the Tx antenna fully extended and the model on the ground. Is this safe to fly??"


Thanks

rc4flying

My Feedback: (21)

Tom,

On the WC II, the antenna is not engaged unless you have the main section pulled up and locked. Otherwise the antenna is not hooked up and a poor range check will result. Unlike all of Futaba's other Tx's, that have the antennas hard mounted. Also, you should never leave the TX on without the main body of antenna up and locked.
Hope this helps.

huey-pilot

My Feedback: (17)

When you do a range check on the Futaba 9Z transmitter you need to extend the first section only, you should feel the antenna click into place as you completly extend the first thick section, the antenna is disconnected from the transmitter when it is pushed down inside the transmitter. With most other transmitters when the antenna is down it is still connected to the transmitter. Also anytime you turn the transmitter on you need to completly extend at least the first thick section to prevent damage to the module. My range checks with both of my 9Z's are in excess of 150 feet with the synthesized modules.

Phil Cole

I don't know where this antenna connection stuff comes from, but is isn't so. The 9Z uses the same antenna as just about every other current Futaba transmitter.

What is different about the 9Z, compared with just about every other current radio, is that the case is shielded, so with the antenna retracted, not much can get out.

Even so, I generally see over100 ft. on a range test with the antenna fully retracted. Extending the antenna even an inch makes a big difference. This is at 50 MHz, using both R149DPs and R148DPs. At 36 MHz the shielding will work a bit better, but the antennas will be less directional, and the path loss will be lower, so I would not expect a huge difference.

With one segment extended, I'll will usually get 200 ft to 300 ft. I save myself the walk by testing with the antenna fully retracted when doing my regular pre-flight testing.

TommyWatson

My Feedback: (1)

Phil,

How much range do you get whith the antenna fully retracted?, I can only get about 25 long paces till the servos start to stutter.
Bringing up 1 section doubles this.

I tend to agree with you about the connection. The antenna slides inside a metal tube. I assume the conection is maintained all the way down by sliding in the tube. However the futaba web site says to range check with the antenna pulled up 1 (first) section.


Regards

RCPilot100

My Feedback: (4)

Phil,

Futaba specifies that a range check with the 9Z be performed with the main section of the antenna pulled out. I don't remember the specifics, but not doing so can cause problems with the radio over time.

Dan

Phil Cole

Dan,

The modules have insufficient cooling on the final transistor for it to operate continuously with a retracted antenna. However, it does cope with the minute or less it takes me to walk 100 ft and wiggle the sticks. I generally turn it off once I'm done testing if the model has a PCM receiver (I mostly use PCM) since the 9Z is a battery hog.

RCPilot100

My Feedback: (4)

Phil,

You are right about the 9Z being a battery hog. I just replaced my 1100 Mah nicad with a 1650 Mah NiMh. Perfect fit. If and when the new 2220 Mah NiMh are available without nipples, I'll put a set of those in. Now if I could just find empty casettes so I could make several spare 9Z battery packs.

Dan

dave Lucas

Hello Tommy ,
It is true about having the 1st section of arial out and clicked . I range check my 40% arobats with Engine running (DA`s & 3W`s) and get fed up of walking with the Tx . I have not encountered any probs . We are on 35Mhz here in the UK .
Keep on Zapping
Dave Lucas

TommyWatson

My Feedback: (1)

Thanks Guys,

I will do some more tests tomorrow. I usually test with the model on the ground which makes things a bit worse.
I did walk more than 1000 feet with the antenna fully extended with no servo stuttering. I will do another test with the antenna up one section and make this my baseline.

By the way my old 9VAP using the same module and RX has an antenna fully down range more than double the 9ZAP.

The model has a 48cc gas twin. So I can then see if the ignition has any effect.

Thanks again for all your input.

Regards

RCPilot100

My Feedback: (4)

Dave,

This is copied from the Futaba website:

How do I properly range check my 9Z?
Extend the thickest, bottom-most section of the antenna ONLY, then range check as you would with any other radio. Please refer to our general range check FAQ for additional information.


Back to main FAQ/Contact Info page

Here is the link where you can find this and other information particular to the 9Z: http://www.futaba-rc.com/faq/faq-9z.html

Dan

Silver182

My Feedback: (2)

Well, if your 9Z series radio, or for that matter your JR 10 channel series radio is tuned properly you should be able to get 300 feet with the trans ant. fully collapsed (F) or removed (JR). Fully collapsing the antenna does not hurt anything, with the Futaba 9Z, but it does reduce the range dramaticly. Note: the recevier antenna should be raised above the ground level 2 or 3 feet during the range check! Doing a range check with the antenna / aircraft on the ground will reduce the range, but more importantly make the range check results very inconsistent. With the transmitter antenna fully extended the same range check should consistently be good at over 2,300 feet or about 4.5 tenths a mile. In fact I am not satisfied until the receiver and transmitter modules are tune to produce a consistent 1/2 mile range.
Lee H. DeMary
AMA 36099

TommyWatson

My Feedback: (1)

I did some tests in my street today. There were some cars parked nearby and the model was on my front lawn, tail on to me, RX antenna inside the model.
With the first (thick) section of the antenna only extended. I got over 100 good size paces(approx 100 yards), with no evidence of the servos stuttering. I could not go any further in the street.

That is good enough for me. I use this as my baseline.

Thanks for all the responses.

Regards

mr_matt

My Feedback: (10)

Hi Tom,

Well I hate to throw more confusion on this, but I usually get 80-95 paces with the antenna ALL THE WAY DOWN in a 9ZAPS. If you move only a tiny bit of the antenna out of the case (maybe 1/2 inch) the range will jump 20-50%. Also, make sure you do this test without a lot of other transmitters on at the same time.

I guess if you have everything working as you want, you can check it any way you want and look for consistency between tests. The problem with that of course is the first test that establishes this baseline. We like this baseline in turbines as it lets us see if any of the turbines computer electronics or systems are affecting the range.

dave Lucas

Hello Tommy ,
It`s Dave Lucas again from the Motherland (UK) . If you got 100 yds on the ground
multiply that by 6 in the air . Your cooking on gas now so get that plane wafting .
TTFN Dave

JohnW

My Feedback: (6)

Have owned a 9ZAP WCI for five years, but basiclly the same as a WCII.

As noted in this thread, range tests should be done with the first segment extended. While leaving the TX in transmit mode for extended periods of time with only one segement up can damage the R/F module (been there, done that), the 5 minutes it takes to range check is not a problem. The overheating/damage problem really only happens if the TX is left on for a long time, i.e. 15 minutes+, like when you are setting up a model. Jesus, the ZAP technician at the Futaba service center, told me it is best to pull the module when setting up planes. One could also start in non-transmit mode (hold lower button when turning TX on) or use the DSC cord.

On range... I always get much better range checks on PCM RX vs PPM RX. From my experience, a PCM RX will typically have a range of 300+ feet. For PPM, 100 feet is typical.

If you have a synth module and synth RX, it is often a good idea to occasionally check both ends and a middle freq, such as 11, 60 and 35. If you find a large diff in range across the freqs (say more than 20%), thier may be something wrong with either the TX or RX.