Espritmodel.com Telemetry Radio
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Old Nov 14, 2012, 11:00 PM
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Lakewood, Colorado
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I'd say it's likely your Tx antenna connector is damaged, as described earlier in this
thread. Your signal strength dropped every time you moved your body (as indicated by
various bumping and scraping noises early in the vid). No kind of external interference
will cause the RSSI to suddenly drop to 50% only 1000ft away.

ian
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Old Nov 14, 2012, 11:09 PM
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United States, FL, Marco Island
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Good point Ian, I'll check that but wouldn't turning and reposition my body cause that and when its stable it progressively degrades.
plus my micro power checks are fine.
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Old Nov 14, 2012, 11:48 PM
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Unless you actually set the Tx on the ground at that point, you should still
see higher RSSI than that with the Tx antenna in just about any
orientation. I'd say the Tx ant connection is intermittent, so a micro-power test may not
show it, if you set your Tx up on something and walk away with the model
(which is the normal way we do that test). Try doing the micro power test with the plane
set on something at chest level 20 paces away and then monitor the RSSI in the video
while gently wiggling the Tx antenna, or unscrew it a thread or two. If the RSSI drops
immediately, you've got a problem. If the connector is ok, you should be able to unscrew
the Tx antenna almost all the way before the RSSI drops.

ian
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Last edited by Daemon; Nov 14, 2012 at 11:54 PM.
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Old Nov 15, 2012, 12:07 AM
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Quote:
Originally Posted by Daemon View Post
Unless you actually set the Tx on the ground at that point, you should still
see higher RSSI than that with the Tx antenna in just about any
orientation. I'd say the Tx ant connection is intermittent, so a micro-power test may not
show it, if you set your Tx up on something and walk away with the model
(which is the normal way we do that test). Try doing the micro power test with the plane
set on something at chest level 20 paces away and then monitor the RSSI in the video
while gently wiggling the Tx antenna, or unscrew it a thread or two. If the RSSI drops
immediately, you've got a problem. If the connector is ok, you should be able to unscrew
the Tx antenna almost all the way before the RSSI drops.

ian
Good advise, I planned to do ground testing tomorrow I will try your suggestions.
Thanks again.
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Old Nov 15, 2012, 01:39 PM
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United States, FL, Marco Island
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Well the Antenna connection appears fine, I can unscrew and wiggle it until the end. Still get about 50m on micro. I did notice my minimum setting on the RVOSD was at 780 when I didn'y really Fail Safe until around 450 effectively shortining the % scale so I lowered the min to 550 which gives me a 0% RSSI about 3m before failsafe. It's obviously easier to get closer to the nulls with a horizontal antenna position so I'll have to pay attention. I'll see what this adjustment does to the readings next time i can fly.
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Old Nov 15, 2012, 02:42 PM
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Do you have the Tx antenna horizontal to match the orientation on the plane?
I've never had a range problem with the stock Rx dipole oriented vertically as long as
it's not near some Rf noisy component on the plane.

ian
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Old Nov 15, 2012, 03:33 PM
Opt
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New Zealand, Auckland
Joined Oct 2010
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Ian, how critical is the receiver placement relative to UHF noisy components? Or is the antenna proximity the only concern?
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Old Nov 15, 2012, 05:09 PM
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It's probably the most critical aspect of using any UHF system. A single Rf nasty
component can cut the range to virtually nothing.
That's why it's critical to do proper micro-power range checks, first
with just the UHF Tx/Rx powered, and then again with everything
on the plane powered up and operating as it normally would
(including GoPro actually recording etc.. )

I had a really nice solid setup on my X8 with the RL Rx antenna
pretty close to the center of the plane. Then installed a very
popular OSD and my range dropped dramatically. Chased my
tail for a while and finally figured it out. I had made
the mistake of not doing a micro-power range test because
I assumed the OSD was Rf clean because nobody else had ever
reported an issue with it. Discovered that the current sensor
was spewing a lot of noise (maybe it's just mine.. maybe not).
Ended up having to move the RL Rx to the other end of the fuse, and
the RL Rx antenna all the way out in the middle of the wing, to get away from it.
Now my range is back to normal.

Note that Rf noise doesn't always cause the RSSI to drop. Because it's
noise picked up by the Rx, it can actually hold the Rf RSSI value higher
while the Rx simply stops receiving packets. That's why for micro power
range tests, I usually set a failsafe position that'll move one of the servos
and I watch both the blinking light on the Rx (blinking slows as it starts dropping packets)
and for the servo to jump to failsafe as I walk away from the Tx.

ian
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Last edited by Daemon; Nov 15, 2012 at 05:24 PM.
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Old Nov 16, 2012, 04:12 AM
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Australia, WA
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Hi Guys, Just had my Plug and play cable break on the plug that goes to my dx8 ( not fixable) Ive found a plug I could use , but it has 2 rings instead of 1 ring on the plug. I ve open the cable up and the only difference is it has unshielded wire that wraps around the white and red wire.

Would it be ok and safe to use this plug?
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Old Nov 16, 2012, 10:14 AM
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Nederland, LI, Herkenbosch
Joined Jul 2011
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99% sure that you could...

Alright, my turn:

I ordered my unit 2 weeks ago, and I got a number which I think is a tracking number. However, I cannot find any website that works to really track that number... Any leads?

-Alex
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Old Nov 16, 2012, 11:23 AM
The lunatic is on the grass
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Quote:
Originally Posted by Aliander View Post

I ordered my unit 2 weeks ago, and I got a number which I think is a tracking number. However, I cannot find any website that works to really track that number... Any leads?

-Alex
Maybe this site can help? http://www.17track.net/
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Old Nov 16, 2012, 12:34 PM
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Canada, ON, Carleton Place
Joined May 2011
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Quote:
Originally Posted by Locko View Post
Hi Guys, Just had my Plug and play cable break on the plug that goes to my dx8 ( not fixable) Ive found a plug I could use , but it has 2 rings instead of 1 ring on the plug. I ve open the cable up and the only difference is it has unshielded wire that wraps around the white and red wire.

Would it be ok and safe to use this plug?
yes it is ok, just make sure you have continuity from tip(at end of plug) to tip and
main body to main body of plug.
The second ring is not used...
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Old Nov 16, 2012, 12:40 PM
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United States, FL, Marco Island
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Quote:
Originally Posted by Daemon View Post
Do you have the Tx antenna horizontal to match the orientation on the plane?
I've never had a range problem with the stock Rx dipole oriented vertically as long as
it's not near some Rf noisy component on the plane.

ian
Yes that's what I meant by watching the nulls.
the IB Crazy turnstile gives a 25-30% stronger RSSI on micro power tests but it is horizontal
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Old Nov 16, 2012, 11:02 PM
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Slovenia, Ljubljana
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Originally Posted by xscorp View Post
Well, so I decided going my way and try it. I have mounted inside my Futaba 9C using transmitter switches for the additional 4 channels by following CW documentation. The new ppm-out is connected to RL module. Now my F9C is converted to a real 12ch system with RL.

The first tests are showing very good results. Next step is to make some flights in order to verify the new system is reliable and secure.

For my next FPV sailplane this is good news!!

JOse Manuel

Jose Hi,
have you made some more tests with your Channel Wizard 12ch setup? I looking for the same solution (needed all 12ch's for my glider).
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Old Nov 16, 2012, 11:44 PM
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Quote:
Originally Posted by jcajhen View Post
Jose Hi,
have you made some more tests with your Channel Wizard 12ch setup? I looking for the same solution (needed all 12ch's for my glider).
I'm using channel wizard to rearrange the channel order on my dx7s for my rangelink .. It works great. Very flexible. I plan on adding a few switches for some extra channels.
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