Make Turnigy module removable with existing hard ware

[kaos]

I just made my new Turnigy 9X module removable for my ERSKY9X and found a way to attach the existing antenna to the module box without any new hardware.

[zann68]

This is how I modded my radio, in this configuration I can use any transmitter module & RX that fits the 9x. I have several planes my FPV uses the DJT / D8R-II Plus and some use the 9x RX. I removed the stock antenna and installed a pigtail in it's place. I had to epoxy the pigtail in the antenna mount to hold in secure. Worked out great. I removed the stock antenna from the 9x module and replaced it with a sma fitting to allow it to be swapped out as well.

Radio with FrSky Module installed

Modded 9x Module with antenna adapter

Back of radio showing the antenna pigtail mod

Can swap antennas as well now

Showing the sma adapter thats epoxied in place

[kaos]

ha ha, i like that Santa.

[minbari]

Be careful with those efl connectors. They pull off boards easy

Sent from my phone using digital farts

[Spoogy]

I just made my new Turnigy 9X module removable for my ERSKY9X and found a way to attach the existing antenna to the module box without any new hardware.

I made exact the samekind of antenna modification about an year ago for my 1st 9x.



And then when I changed to 5db antenna I modded it like this:






The plastic part for the antenna mounting is a cap from a perfume bottle. It's still there and working great.

[zann68]

ha ha, i like that Santa.

Had my youngest son hold the radio for me

[kaos]

2nd from the bottom pic, Looks like the Santa was mad at you and snapped your antenna.

[Clivew]

I know it's expensive, but the spektrum SPM6817E case seems good, it puts the aerial/antenna/twig(!) above
all the metal, and I guess would take any module with a bit of fiddling? (I don't work for Spektrum!)

[ShowMaster]

I'd like to remind everyone that every connector in the path subtracts from the 60 MW output. It's not like 72 or other frequencies where we started with 3/4 to 1 watt of output power. There is a point where the output power is reduced a lot. It all look great in our minds but in practice it's not always the best way to go. With the Frsky setup it’s easy to see what your range is because of the built in power reduction option. Has it been proven the FlySky module can have its power reduced to verify there is no range issue?
In close it all works. Sorry to bring this up but RF is a very serious technology that a EBay connector and a drill may not have all the answers for. The FlySky module was designed to maybe not have the impedance loss of an added connector (3db)? If you value your plane tread lightly on all the antenna mods.

[andrewju]

I'd like to remind everyone that every connector in the path subtracts from the 60 MW output. It's not like 72 or other frequencies where we started with 3/4 to 1 watt of output power. There is a point where the output power is reduced a lot.

Hi All,
I'm a 9x user for quite some time now and recently my stock antenna became very loose - the moving part of it (the antenna itself) does not hold well to the base. I was thinking to replace it with a totally new antenna, and preferably make it removable - but I have exactly the same concern: I'm afraid the signal loss caused by at least one connector (and I was actually planning two in order to make the module removable) will reduce the range.

Still thinking of how it can be done with minimal risk...

[gohsthb]

Still thinking of how it can be done with minimal risk...

I goggled around and found a typical connector loss is 1/4 db. So if you don't have many of them it should be fine. It also depends on how well you installed the connector and how good the coax connections are to it, so YMMV.

On another note, I was at a seminar this weekend where a guy from Horizon Hobby was talking about the new DX18. You know the whole thing about if you have 2 receiver antennas, that you should keep them at right angles to each other? According to him the difference between running the antennas parallel or perpendicular (as suggested) is 30db! I think someones question was about increasing the power output of the radio. To get the same gain by increasing the power output you would need 1000 times the power output. Our radios would then need a 60 watt output!
Just interesting information I learned,
Gohst

[ShowMaster]

1/4 db loss is not much for line of sight flying. Much better than the 3db I posted as maybe? My thoughts are that modules that come with a removable connector all ready factored into the design should be more efficient than one one designed to not have the connector. Adding one would add some loss. In the end a ground range check before and after should tell something. The trouble is I don't know if the FkySky/Turnigy modules have a low power test option. It's been discussed but does it exist and if so what's the power reduction?

As for 30 db, every 3db is 1/2 power as I remember so that's 1/2 power 10 times from the original 50-60Mw, wow!



ShowMaster
Sent from my iPod touch using Tapatalk

[kaos]

sounds like the way I did has the least amount of signal loss, no connector, just resolder the antenna back on the board.
I had tinkered around to solder a ufl connector on the stock module board, but figure it is harder to do that than solder the wires directly back on.

May be this the reason why the stock Turnigy did it this way, direct soldering instead of ufl, with a cheap Tx still has pretty good range compared to other name brand.

[Kilrah]

Depends. A bad solder or one with leftover flux can lose much more than a connector.

[kaos]

looks like I need to drive 800m to find out if I have a bad solder.

Actually, that is a good idea. I don't think I ever did a LIve range check on my Tx. Take all my 3 T9X with all my removable module and set up a oscillating servo, drive as far as I can on a straight flat road to see which one dies 1st.

[jhsa]

or maybe put your tx in servo test mode inside a microwave oven.. just don't turn it on and keep wife and kids well away from it..
The oven it will hopefully work as a Faraday cage and reduce the power of the signal.. if not, get rid of it

[kaos]

question is how much this Faraday cage is reducing the singal! I don't think the Flysky module has a way to do range check??

[jhsa]

it doesn't matter how much.. I think it will reduce a lot.. at least it should.. but like this you should be able to test and compare modules with and without connectors without walking a mile..
Just my 2c
Joäo

[Kilrah]

Inside a microwave oven you should have nada.

This thing IS a shield made to constrain 1kW of 2.4GHz RF inside without letting more than a couple of mW get out. So don't expect much of your 100mW to get out

[kaos]

hmm, that is an idea. at least I can compare the one I soldered with the stock one I have on the other Tx.

Talking about the signal strength. Telemetry is new to me. I think RSSi is an indication of signal strength. what is an acceptable rssi number, what is critical and what is signal lost (beside 0)?


Edit: and I just tyried the microwave. It does work. compare the the stock Flysky removable module, my module has less distance than the stock Flysky. But mine is a Turnigy, the stock is a Flysky that Ghosthb sent to me. Don't know there is a difference to begin with with turnigy and Flysky.

my microwave is enclosed in a brick wall surround, and my house is all brick all around (except doors and windows of course), the Flysky module can send signal to the farthest part of my yard whithout glitch (servo still sweeping, appears normally), but the one I made is about 10 yard short of the fence and stopped functioning. Looks like I need to clean that solder joint a little. I made sure there is no contact between them (check with a 200X video scope from ebay for 30.00, it is pretty neat little scope for examining;) )but I did not realize the flux will reduce the signal too. did not clean the flux. what is the best thing to clean the flux after soldering?

[kaos]

Inside a microwave oven you should have nada.

This thing IS a shield made to constrain 1kW of 2.4GHz RF inside without letting more than a couple of mW get out. So don't expect much of your 100mW to get out

It did go out. The one stock Flysky module I would say about 15-20 yard from the house, another 10-15 yard from the house wall to microwave oven and still no glitches. the one I made only reached 10 yard outside of the house and stopped.

[Kilrah]

Talking about the signal strength. Telemetry is new to me. I think RSSi is an indication of signal strength. what is an acceptable rssi number, what is critical and what is signal lost (beside 0)?

Every manufacturer displays their RSSI differently, so it depends who you're talking about...

[kaos]

Wow, this is unbelievable!

Just out of curiosity. I put the DJT and a D8r-xp to repeat the same test. same location everyone. You would expect Frysky has better Tx/rx. Nope!!!!!!!!

The D8R-XP stpped dead exactly the same place where my home made module was. More, my home made module after that point may occassionally get a twitch or sweep after another couple yard. The D8R-xp stopped dead at the point where the servo stopped functioning and no twitch what so ever after that.
Under this condition , it seems the Flysky removable module has a lot better range. wooooooooow!
all 3 has a 'stock' antenna on it (4 db ?? , any way the regular antenna).

[Kilrah]

The stock flysky sometimes transmits with a bit more power, actually too much to be legal. That's one of the reasons why 9x's get confiscated by customs in some countries.

The whole point is that flysky is less consistent - as you could see. With frsky you know a bit more precisely what you're getting into, less sample variation.

[kaos]

out of the 2 flyky removable, the one I made is surely has less range/power than the Flysky module. but I don't know it is because my soldering or just the board.

Now this is getting more and more interesting. I figure I might as well test my DSMX moudle as well, it took me a while though, forgot about the model matching, and the rx never responded to whatever I do. finally realized the model matching thing. rebind and it worked.
so, all condition the same, same ersky9xTx, same kind of antenna, same oven , using an orange rx with satellite rx once I step one step outside the door, the sweeping servo stopped. one step close to the door, it resumes. I don't know about ARrx but orange rx with satellite is worse than any of the other here.

now even more interesting, I repeat this with the satellite rx off, it should get worse. Nope!, it actually goes half to one step further than with the satellite rx. Hmmmmmmmm
looks like the 11.00 satellite is a total waste compare to just a 5.00 rx itself. or it may not add the range but add to the reliability?

[Kilrah]

half to one step further than with the satellite rx

A step with obstacles around (your house walls), random RX and TX orientations means absolutely nothing. I'd be tempted to say the previous test means nothing either. If you want a good comparison, take your microwave oven out on the driveway, put it on a table, set each of the TXs so that their antennas are always at the same location inside the microwave and with the same orientation, then walk away on the same path with all systems with the RX antenna always in the same orientation (parallel to the TX one).
Then we can start getting a more or less relevant comparison. Placement of the TX antenna in the microwave can change results, TX/RX orientation WILL change results a lot, etc...

looks like the 11.00 satellite is a total waste compare to just a 5.00 rx itself. or it may not add the range but add to the reliability?

A satellite won't increase range at all. It will only potentially pick up a signal when the main receiver won't, simply due to their different location and orientation.

[kaos]

A satellite won't increase range at all. It will only potentially pick up a signal when the main receiver won't, simply due to their different location and orientation.

that's what I thought too.

A step with obstacles around (your house walls), random RX and TX orientations means absolutely nothing. I'd be tempted to say the previous test means nothing either. If you want a good comparison, take your microwave oven out on the driveway, put it on a table, set each of the TXs so that their antennas are always at the same location inside the microwave and with the same orientation, then walk away on the same path with all systems with the RX antenna always in the same orientation (parallel to the TX one).
Then we can start getting a more or less relevant comparison. Placement of the TX antenna in the microwave can change results, TX/RX orientation WILL change results a lot, etc...

hmm, makes sense in theory. As it is, it is under one same condition though. under this condition, I think the Flysky has a lot more range than the one I made and Frysky. I did put the Tx inside the oven exactly the same way, or as close as possible. But the yardage is 15-25 yards different (and the Flysky is not even showing signs of any weakened signal while walking around in my yard at all. don't want to climb over the fence. where I am, people can shoot you for transpassing without asking questions. ) I walked around in the yard at different location like a circle with these 3 modules.
Darn it, the moisture around may be even different, I was circling around the pool.

[jhsa]

well, it seems that this test is as reliable as any other range test where you have to walk or drive.. you never place the antennas exactly the same when you walk either.. the difference is: you don't have to get tired

[kaos]

yep, which also means I need to throw away my microwave because I will be cooked after a while just sitting in the kitchen.

[rperkins]

Maybe put the reciever in the microwave and move the tx.
Or at least unplug the microwave.

I bought an inexpensive ISM (2.4ghz) usb spectrum analyzer and the 2 microwaves I tested spewed garbage. And my microwave was top of the line only 1 year old.

I spent 4 years in a 'screen room' faraday cage, repairing pagers. It was serene.