SpeedBird

Ok Help Everyone...

1. Went to the field, and at 20 to 25 feet with antenna down on Trakker II, range test failed. All control surfaces jittered.
2. Using all hitec servos at 4.8 volts and a Seeker receiver.
3. Temp 60 degrees, with light drizzle.
4. Two days prior, friend had problem with his Futaba trans and/or rec but could not isolate the prob. He changed rec and seems to work ok now.
5. At the field today, ofcourse I did not fly. But lost 5 hrs trblshooting with the gang.
This is what we did....

a)Changed the bat from 4.8 nmh to 4.8 nicad, jittered
b)Pulled all leads from all channels and tried to see if a single servo was drawing too much by reintalling and checking; jittered
c)Used friends 9c transmitter; jittered
d)Used second Trakker II radio; jittered
e)Used third Trakker II radio, jittered
f)Swapped 4, yes four(4) Seeker receivers; jittered
g)Went home to see if problem related to location; jittered---however, it jittered at night, the next morning it was ok.

Thus was ready to go the field the next day. But prior to heading to the field. IT jittered.

Now, I figured let me rearrange the antenna away from the battery leads: jittered
At the field, jittering occured with the antena down at various 20 30 60 feet. So, we pull the ant all way up and walked...
At 300 feet it started to jitter again.

h)We turned off all cell phones; jittered
i) We used a seeker rec off the plane, with another batterypak and a single servo on the bench; jittered
j) We changed brand of servos to futaba; jittered
k) We eliminated extensions; jittered
l) The plane was on a metal stand, we took it off a metal stand; jittered

Goblins, we figured...
Actually, I'm beginning to think its the path Venus is taking between the earth and the sun.

I remind you this is the second day I'm grounded. After another 4 hours at the field. BTW, the plane is an extremeflightrc 540t.
A beautiful plane, even my wife says so.

Now, my friend and I say lets go home and try it with a crystal receiver. and the futaba crystal radio.

I take to Seeker off, and install the fm crystal futaba rec. NO JITTER and solid control surfaces at 60 feet with futable fm transmitter. NO JITTER and solid control surf at 50 feet with Trakker II.

What's happening? BTW, John Gil at Polk is so far providing excellent service, and said all will be rectified.
But what is happening? Can it be that all four receivers are bad?
So far all is working well with a crystal so far.

SpeedBird

N1903Z

Any progress on finding the problem with the Seeker IIs, Speedbird? Can't believe four bad Seeker IIs. Thanks.

DBCherry

My Feedback: (4)

I guess I'd suspect stray signals from pager services or something. With your Tx antenna collapsed, the Seeker Rx might start seeing other signals and try locking onto a stronger one.

I too would like to know the outcome of this. I've considered the Polk system and want to know if there are issues with it.
Dennis-

SpeedBird

I brought three receivers and my extreme 540t to Polk. We tested inside the facility and out in the parking lot. Jitters all over.

Finally, they kept my transmitters for upgrade to 1.35. But there appears to be nothing wrong with the transmitter. The receivers, however, maybe out of "tune."

And have to be retuned.

I will give results when I get systems back.

Ciao all.

SpeedBird

Lee MRC

Speedbird, sounds to me like a phaselock problem. I know that with synthized amature equipment there is a low level "phase shift" noise when you do not have the receiver tuned to a station. This is to say that with a "hot receiver and low level or no input signal to lock onto, the phase lock loop will "hunt" for a signal within a preset frequency range either side of it's center frequency.

I realize that this a complex answer but it is also a complex situtaion.


Try extending the transmitter ant. when you reach the distance at which the "jitter" begins and reply if you can and I will attempt to assist you if you desire.

The reason that the crystal controlled receiver did not "jitter" is that they do not utilize a phase lock loop for frequency control.

I sure hope you get your problem solved as it is frustating to have a nice toy and not be able to go out and play.

Fly the airplane first,

Lee K5MRC

SpeedBird

Hi Lee,
Thanks for your input.
According to Polk, they told me that the receivers are out of tune. Thus I have given them all nine to "retune."
Whenever I speak to them, they are always willing to help and make things right.

Thus far, I have received two of the receivers back and one transmitter upgraded to 1.35v.

At the field, as I have only used the one receiver, no jitters at 60 feet with the transmitter down.

Polk also said that when locking the rec signal, you must extend the antenna fully when locking in. This will give the rec a narrower channel to lock into.

So far so good. Can someone explain to me why all four receivers (at least) went bad at about the same time?

Thanks
Speedbird

Lee MRC

Speedbird, thanks for the reply not all people do, they are correct in their reasoning and I might add honest. Glad you got your problum solved and can now GO PLAY with your new toy. They sound like a good conpany to do bussines with, I will remember that! Hope that you have a good week.

fly the airplane first

73,

Lee K5MRC

Sander

My Feedback: (2)

Speedbird,

I use the Traker/Seeker T/R combination. I have noticed that the amount of "flutter" will differ from channel to channel. For example, I have no problems using channel 36 but channel 44 us unusable. Check different frequencies (channels) and see if some have less flutter than others.

Cheers,

Sander

rare_bear

My Feedback: (1)

april fools day - polk seeker style


yep, i have experienced the same problem of jitter.

first time seeker user did his range check on his new mustang.
walked 30 feet away with Tx antenna collapsed - jitter
walked 300 feet away with Tx antenna deployed - jitter

noted that jitter get's worse with increasing distance.

end of range test.

==============

a couple of months ago, i was measuring battery consumption on my other airplane which utilized a hitec RCD3800 (7 channel FM receiver) and the 5 hitec servos that are connected to it. i hooked an ammeter (an old fashioned analog style with needle & inductive coil) between the battery and the receiver. measured the current. okie dokie. then i took the same setup over to my mustang just for comparison and i was surprised to see the seeker II jitter with the ammeter connected in the battery line. when the ammeter was disconnected and batter reconnected directly to the seeker II, the jitter disappeared.

hard to believe the magnetics from the ammeter coil could induce instability in the seeker II and yet, the hitec RCD 3800 was immune.

what i wonder, as a practricing electrical enginner, is whether polk has shielded the case well enough or done a good enough job on power supply decoupling.

============

well, whatever. as for this april fools day, i went down to the hobby store and bought a new hitec 8 channel supreme to replace the polk seeker II. i wanna try to do a maiden and the last thing i need is an unstable radio receiver.


hope polk get's their act together - someone in here said that theirs needed to be retuned. tuning my a*s.... i've had 4 reports from a friend of mine today who said 4 other people that he talked to at his hobby shop who have reported the same problem. jitter.

nope - no april fools actually.... unfortunately for polk.

LEWIS POLK - IF YOU READ THIS, investigate the instability i refer to with the DC ammeter connection.

-pw

SpeedBird

Wow, interesting.

Gene Chernosky

My Feedback: (182)

I had a Polk radio system once...ECCH! [:'(]

I wouldn't hesistate to bulldoze every Polk radio product I could get into a pile. They are over-rated 'wonna-be' products.

Campy

My Feedback: (1)

I don't know. As with ANY product, you will have people who swear by them and people who swear at them. I know people that you couldn't GIVE a particular brand/model radio to and other people who would kill if you tried to take away their radio (name a brand ) and replace it with another radio (name a brand).

For myself, I have a Futaba 6XAS and a Tracker II. I really like the Tracker II. I had one problem with the transmitter about 2 months after I had it and it was taken care of promptly at no cost to me.

speedster 1919

My Feedback: (3)

I'm no expert and don't own one. But I think I read they have to have 6volt and will be unreliable on 4.8 volt. Sounds like you did everything but go to 6 volt.

Campy

My Feedback: (1)

I use mine at 4.8 volts with absolutely no problems. In my 8 planes I have had one problem - a servo that "twitched". As soon as replaced the servo, the problem went away.

lewispolk

We have been making Seeker recievers for several years now, with many thousands on the market place. If you have any difficulty with them drop them in a first class mail package to us and we will check it out. It's rare that we can't fix it to everyones satisfaction and it's a no charge deal to you.

More people swear that they love the radio and only a very small percentage swear at it. We have many ordes waiting for the new version and that's the truth. If you can't get your system to work, the please call in for assistance. It is a complicated device, but our tech people can make it work easily for you. Some of the top flyers in the country like Tom Hunt, Bob Aberle and Leion Shulman who can't live without them. Perhaps the person having difficulty should call for help to see why the can't master this device

Yours truly,
Lewis Polk