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Old Oct 26, 2012, 08:20 PM
BEOWULF
North vancouver, B.C. Canada
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Mmmm
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Old Oct 26, 2012, 08:33 PM
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Daemon's Avatar
Lakewood, Colorado
Joined Aug 2002
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David, I don't normally even see your posts at all unless someone else quotes you,
but since you replied 7 times, I went ahead and clicked "View Post" link to take a look,
and it's the usual misleading nonsense. You are wrong. Yes UHF Rx's require filtering
to block external Rf but so do UHF Tx's. All *good* radio transmitters have filters.
Every radio transmitter generates harmonics, especially powerful and
relevant to us at 2nd and 3rd order.

The 2nd order harmonics for 433Mhz can affect 900Mhz video for cheaper video Rx,
and the 3rd order harmonic falls square the middle of the 1.3Ghz band and is
impossible to block on the video receiver side. The *ONLY* place you can filter
it out, is on the Tx side. Some UHF Txs have filters built into the kill the harmonics,
and some do not.
Per Thomas, in post #22 of your favorite thread
Quote:
Originally Posted by thomasscherrer View Post
I have harmonic kill filter, however it is always impossible to opperate a TX and RX in the same area on exactly the double or trible frequency,
If you don't believe that UHF Tx's need harmonics filtering, ask Thomas yourself.
TSLRS has always had fairly decent filtering but even it has had room to improve
over the years, and has improved.

DL has evolved a lot over the years. It used to have much less harmonic filtering on the Tx,
and you could see visible noise on 1280Mhz it they were too close. The upgraded DL V1
units improved this quite a lot. I assume those same improvements are in DL V2 as it
shares a lot of its hardware with RL.

RmileC and Chainlink have little or no harmonic filtering on the Tx, which makes
them pretty worthless to use around 1.3Ghz video gear, unless you install
your own 433Mhz low pass or band pass filter between Tx and antenna.
Without the filter on the Tx side, it doesn't matter which 1.2Ghz VRX you use.
You just can't stand anywhere within 10m of it.

RL, as one of the later players built pretty good filtering into the Tx and Rx to begin with
although Sid did have to tweak the radio (via firmware update) to kill a small harmonic
that was appearing on 1280Mhz. Not sure how he fixed in software, what is normally
a hardware issue, but he did.

I own and have used all of the above systems except Chainlink but I've been
near one, and it's a mess.

ian
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Last edited by Daemon; Oct 26, 2012 at 08:39 PM.
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Old Oct 26, 2012, 08:43 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,581 Posts
I was unaware the UHF tx also had filters

I will look into that

What do they filter

The out put should be constant and regulated as specified

I correct you before and help you but you have blind eyes sometimes

Smarter to say you read and see everything but rather not discuss rather than play blind or stupid


And think you never wrong

Why filter specific out put when input is most important

Hard to explain to someone with no eyes or cannot see as you
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Old Oct 26, 2012, 08:47 PM
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Lakewood, Colorado
Joined Aug 2002
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Just the fact that you're replying, tells me you didn't actually read what I said.
Harmonics. Look it up. I won't respond again.
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Old Oct 26, 2012, 09:25 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,581 Posts
Funny because I use original Thomas UHF tx
One of first designed with actual Japanese components
Version 1

Others more mass produceded
But say the same per say

No new filters at all in the tx but only in the new rx versions
As example new dragon link version rx UHF
Big big difference in filtering from orrigionl

You see 1.2 video filters as example are just on the rx not the tx
He put frets in for 2.4 and other so UHF rx can be not effected by video tx and noisy components

Many do not see this and major problem as some UHF rx are poor

As the dragon link recently put in their systems or specifically the rx of the UHF rx as Thomas does or has

The filter as you think in the tx is not important it is not there

You argue or try to get things right in the wrong way

As first UHF tx from Thomas works same as present tx for UHF
Only difference is power out put ant cooling as example

It's the rx that is different

Look on web site and see difference is only the rx side that has filter
Not tx UHF

Same as dragon link as they are basically same partners

Daniel and Thomas are buddies and share stuff and ideas

1 idea is failsafes in flight other example is filtering video interference
From 1.2

Of course Thomas came up with 1.2 and other filtering g for UHF rx interference
And Danielle is genious with other ideas

But you got it wrong as orrigion UHF systems even the dl and thomas system works better becuase of new improved filters only the rx side

This is why the dragon UHF system gives free upgrades to the rx for UHF

People are not sending in the UHF tx for upgrades but only the UHF rxs to get filters

V

You see but cannot

That is big problem
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Old Oct 26, 2012, 09:32 PM
Power-line attraction pilot
United States, MA, Natick
Joined Jun 2011
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So, just to change the subject so the post count kings don't go neck to neck... Is RL as good or better than DL?
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Old Oct 26, 2012, 09:37 PM
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Lakewood, Colorado
Joined Aug 2002
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Please go ask Thomas (or Daniel, or Sid) before you spew any more incorrect information about the need or lack thereof for Tx filtering.


Quote:
Originally Posted by caall99 View Post
So, just to change the subject so the post count kings don't go neck to neck... Is RL as good or better than DL?
By what criteria?
I've ranged tested both over 30 miles. They now share much of the same hardware. DL V2 has added
a few new features, which RL actually had first.

ian
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Old Oct 26, 2012, 09:45 PM
Power-line attraction pilot
United States, MA, Natick
Joined Jun 2011
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I guess that answers my question. They appear to be equals by most standards... Is there really much of a difference?
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Old Oct 26, 2012, 09:58 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
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There is no filtering needed or new filters added in new UHF txs but only the UHF rxs

Please post link to filter added to either Thomas Or dragon link tx to showme I am wrong

I am interested in see I g link or proof that old UHF tx and new UHF tx have different filters if any

I would be surprised if there were new filters in the recent UHF tx versions

A link would be greatly apreciated





Quote:
Originally Posted by Daemon View Post

Please go ask Thomas (or Daniel, or Sid) before you spew any more incorrect information about the need or lack thereof for Tx filtering.



By what criteria?
I've ranged tested both over 30 miles. They now share much of the same hardware. DL V2 has added
a few new features, which RL actually had first.

ian
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Old Oct 26, 2012, 10:02 PM
Cape Cod
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Cape Cod
Joined Sep 2010
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David22,

I have been reading this thread lately and must say you do have many of your facts completely wrong. Needless to say it would take too long to cover each one separately. I will comment on your last Fact", People are not sending in the UHF TX for upgrades but only the UHF rxs to get filters. Well thats wrong again. First the Tx has to be sent in with the Rx's so they both share the save version of their respective software when upgraded. Also the upgraded Tx is a completely new TX, not just a software upgrade.

In closing I will tell you that In reading his posts and asking questions I have found Daemon to be one of the most knowledgeable and experienced posters here on the forum.

Everyone Have a Happy and safe Halloween,

Tom
Cape Cod
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Old Oct 26, 2012, 10:12 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
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[i am interested in my last question could you provide a link

I don't think the UHF tx needs to be any way brought in or sent in with the UHF rx to get new filter


And say you at wrong wrong wrong

As new versions of rxs even with new improved 1.2 filtering are compatable with first versions or orrigionl UHF txs

So be carfull of your posts not to look stupid or wrong


QUOTE=tom3holer;23110900]David22,

I have been reading this thread lately and must say you do have many of your facts completely wrong. Needless to say it would take too long to cover each one separately. I will comment on your last Fact", People are not sending in the UHF TX for upgrades but only the UHF rxs to get filters. Well thats wrong again. First the Tx has to be sent in with the Rx's so they both share the save version of their respective software when upgraded. Also the upgraded Tx is a completely new TX, not just a software upgrade.

In closing I will tell you that In reading his posts and asking questions I have found Daemon to be one of the most knowledgeable and experienced posters here on the forum.

Everyone Have a Happy and safe Halloween,

Tom
Cape Cod[/QUOTE]
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Old Oct 26, 2012, 10:19 PM
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Birmingham, Alabama
Joined Jun 2002
2,970 Posts
I've burned up four fox-700's and 800, a sunsky 800 and the one lawmate I ordered was DOA. It's hot in Alabama summers prop wash or not, 90-100*f temps and 90-100% humidity is not indicative to cheap Chinese electronics... Some stock, some deceased with heat sinking applied with that epoxy, some taken apart, applied article silver & reassembled. All burned up. (well one fox died in a crash, but it was on its way out)

However, I, LOVE those sunskyonline 1500mw units. Regardless of the fact they all come from Mc Brain, the design and build quality is just higher. They run hot to the touch and are expensive, but I've been impressed by them. If only the smaller units were as good. Idk maybe it's bad luck... Doubt it.
I've never had an issue with that much power, but keep in mind everything I fly has more mounting room than something like an easy* clone, zephyr or skywalker & I don't use cheap Chinese rx's and servos with fpv so. Your mileage may very with 1.5w on a small plane.
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Old Oct 26, 2012, 10:44 PM
Cape Cod
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Cape Cod
Joined Sep 2010
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David22,

Perhaps I read your post wrong.

"This is why the dragon UHF system gives free upgrades to the Rx for UHF

People are not sending in the UHF TX for upgrades but only the UHF rxs to get filters"

I read this to indicate you are talking about the DL UHF Tx's not being sent in for upgrade.
If I am wrong I do apologize. If however if, indeed, you were talking about the DL system then it is you that is wrong, and one wrong is sufficient. Both need to be sent in together as I indicated in my first post along with the reasons why. I have a V1 system that has been upgraded and know quite well that both have to be sent in for upgrade.

Tom
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Old Oct 26, 2012, 10:58 PM
Power-line attraction pilot
United States, MA, Natick
Joined Jun 2011
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Hey ian, your 30 mile range test was without any other Fpv equipment on right? Could you give me a better description of how the test was performed?
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Old Oct 26, 2012, 11:59 PM
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Lakewood, Colorado
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Quote:
Originally Posted by caall99 View Post
Hey ian, your 30 mile range test was without any other Fpv equipment on right? Could you give me a better description of how the test was performed?
In both cases, the UHF Tx with stock RL antenna was placed on top of a tripod on a small
mountain on one side of town, and the UHF Rx was installed in my Skywalker with all FPV gear
powered (FOX800 VTx with Vee antenna on the tail). Stock UHF Rx dipole antenna run
vertically up the side of the fuse. Transmitter set to cycle the channels (ESC powered
but disabled) so only rudder and elevator were moving (wings removed).
Have a large visible LCD RSSI display installed on the plane. Plane fuse taped to the
dash of my car with RSSI display in view. Started driving east from one side of
Denver metro area to the other. All the way to DIA airport. Distance from UHF Tx to
Rx while passing through the upper departure drive through area of the airport is almost exactly
30 miles, and servos were always cycling as long as I had clear LoS to Tx. For 2nd
of two tests, I drove back out to I-70, and kept going east till running out
of LoS, RSSI dropped below about 20%, and servos stopped at 36 miles.
I only took RL to 30 miles, and it was still going strong. Took DL to 36 miles where Tx dropped
below the horizon.

Note that if you put some Rf noisy components onboard the plane, you can still cut your
UHF range to practically nothing. A 30 mile range test doesn't mean you'll get 30 miles
in the air. A plane in the air actually sees more external Rfi than one on the ground.

ian
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