971wright

Hi Guys Has anyone screened there motors with wire mesh to create a fariday screen to cut interferance with radio? Would it help ?Or would it be a waste of time ?I have a panzer 3 the range is bad tried allsorts of different ariels no change range is about 60ft if this is a none starter will have to change to 2,4ghz was hoping to keep this one 27mhz cost on radios is very expencive .





regards pete

fv432

Hi Pete not sure if this helps mate but one of my PZ3's had crap range also
when i pulled it apart i found the aerial lead had been trapped between a screw fixing and basically cut the inner wire in half[X(][X(]

replaced the wire and back to top range again


Regards Rob

971wright

Hi Rob Tried just about everything new boards different ariels different motors . still stays about the same must be the schurzen blocking the signal or R.F. from motors which cant dispate because of schurzen it looks like will have to change to 2,4ghz when Ifit the dbu /dbc wanted to keep it 27mhz am but needs must dont have any problems with any other tank ,think ill fit a recoil unit at same time .Just thought Iwould ask the Question in case im missing some thing need one of them electomagians to say if it would cut R.F.when you think about it there are 7 motors inside the panzer3. 2 drive motors 1cooling fan 1 smoke unit 1 turret turn 1 elevation motor 1 gun motor . plus radio gear 2 batteries now ive got to find room for the dbu/dbc units and wiring also if another reciever .its going to look like the inside of the wifes handbag .


best regards pete

P.s looks like one of the batteries is coming out to make room .

gigantohawk

Hi Pete, I've been away a while trying to make sense out of this Credit Crunch Nightmare. However, have you tried the Pzrwest Aerial Coil. It worked a treat for my PZIII.

Regards,

Nick

971wright

Hi Nick Yes tried coil ariel started with 1/4 wave length then 1/8 wave still no joy standard ariel still have range of 60ft. this has me scratching my head dosnt mater what I try still the same.thats why Iwas thinking the schurzen was blocking in R.F. from motors and interfering with radio .




best regards pete

heavyaslead

The capacitors on the motor lead provide the interference protection. A Farady Cage will do little to no good for this application.

Wozwasnt

I think that some of it may be down to the transmitter.

I could run my Tiger to about 100 foot without an aerial on the tank. But one day I dropped the transmitter and it smashed, no problem, I thought, I've got others. But my three other transmitters will only work to about 50' even with an arial on the tank.

It's not really that much of problem because I don't run it that far from myself (I'm too lazy to walk to it if it gets stuck).

fv432

Pete
been thinking on this have you tried connecting aerial to the schurzen plates ??

Rob

971wright

Hi Rob yes tried it done about everything different motors new capacitors new boards different transmiter this problem only started after fitting schurzen .so if the schurzen is causing the drop in range must be either stopping signal which it cant be because it works or it is not letting R.F. disipate if you like the schurzen is turning into a fariday cage .so the only way I can see to stop this is make a fariday cage around the drive motors ,then the R.F. will be contained and shouldnt interfere with radio. I cant think of anything else really need a radio ham who knows alot about what causes a reduced signal strength .


best regards pete

fv432

tough one mate but i reckon your right with the schurzen[:@][:@]

probably don't want to do this but why not re-make the panels from plastic instead ??

I'll go away now LOL


Kind regards rob

gigantohawk

Pete mate. Not wanting to disrupt your line of thought on this issue and believe me it's making my head hurt as well. But from my recollection a Faraday Cage needs to be grounded for it to function. In other words if your Schurzen is mounted on plastic and not "earthed" then it won't behave like a Faraday Cage. So your loss of signal range is due to other factors.
Try re-locating the aerial coil to an area within your tank that is away from electro-magnetic forces.

Let me know how you get on.

All the best mate,

Nick.

heavyaslead

You know thinking about it again, the schurzen could act like an RF trap.

If the schurzen is metal and mesh of appropriate dimensions, it could act as a sink for RF signals.

If the schurzen is non-metalic that would aleviate the issue.

971wright

Hi Heavyaslead this is my line of thinking ,thats why Iwas thinking of sceening the motors with mesh to reduce R.F .




regards pete

darkith

I've heard of heli pilots improving range by shielding their RXes with tinfoil (presumably by keeping the RF out). So it's possible that trapping the RF by wrapping the motors might help...but in some ways their already wrapped in cans, so the leakage would only be at the brush housing and through any cooling slots.

Course, if you insulated the RX with electrical tape or something, you could try wrapping it with foil as well.

D.

123Splat

To my way of thinking, Heavy's right about the 'Faraday Shield'. It would have to be grounded, not floating to have any positive effect. Otherwise, it is just an antenna for the RFI from the motor brushes. I think the same logic follows for a recvr shield. IE: you would have to tie it to ground (Batt -) to be effective. If RFI is the problem, best bet is .01 to .02 ceramic caps on the motor leads (one from positive to motor case, or the trans case, and one on the negaive to the case).

A simple field strength meter (a diode, a wire loop, an Op-AMP, and a voltmeter) can be used to see how yout xmitr is propagating.

If you are still convinced that it is the recvr, try replacint the antenna lead on the recvr.

971wright

Hi 123 splat If I fitted brass mesh over the motors and solder in postion soldering to gearbox this would be earthed because its metal drive sprocket metal track . this contain then dispate any R.F. shouldnt it?


regards pete

heavyaslead

ON A SIMPLE NOTE, the small tuning adjustment (inductor) on the receiver circuit board may be just out of calibration.

Who knows what range quality control has to satisfy at the factory? I doubt they do a range test, probably just see if it fires up on the bench at arms length.

darkith

Not sure. I don't recall that those who found it helpful tied it to Batt-, but perhaps.
I think a car blocking GPS signals is a good example of a Faraday-like cage that *isn't* grounded. Affects cell signals to some degree as well, but the towers are more "visible" through the windows than GPS satellites in the sky are.

And according to wikipedia (the fountain of all knowledge....or lies, depending on the last editor), a Faraday cage doesn't have to be grounded to work:
http://en.wikipedia.org/?title=Talk:...be_grounded.3F

D.

Chally2

I'd be tempted to try a new antena cable, HL cables seem to be variable. Some are fine but others are quite brittle and seem to be of poor quality.

Go back to basics, as Sherlock Holmes said:-

“Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.�

This has worked well for me so many times in my life.

123Splat

My mistake, I guess. I thought that the shield had to be grounded to dissipate the assorbed energy, but this would only be viable if you had a metal hull.

Darkith,
I yield to your experience and knowledge.

heavyaslead

Not sure if this point was clear or not from my first response, but the Faraday Cage for the motors could cause even more interference with the RF signal since it can trap incoming RF radio signals reducing range or if not designed properly, can actually act as a feild transmitter or motor noise.

All the years of engineering point to using ceramic capacitors as the best solution to suppressing motor RF noise.