My Transmitter Conundrum

[Mad_Mechanic]

@Kendalf - I don't really have any good links with help for extracting 18650 cells. It depends on how each laptop battery is built.

 

[Kendalf]

You can buddy box anything with a 3.5mm jack with Open TX, if the other radio doesn’t have that you can buddy it using a spare receiver.

So I took on the challenge today of soldering together my own trainer cable to buddy box a Turnigy TGY-i6S (clone of the Flysky FS-i6S) to my old Spektrum DX6i. I was able to find out the respective pinouts for the PPM output and found some spare S-Video and mono 3.5mm audio cables to cut apart and splice together. Got everything nicely soldered together and heat shrink around all connections, and was pleased that the cable worked perfectly well once I plugged the two controllers together and flipped the Trainer switch on the Spektrum. Only problem was: Spektrum uses TAER for the channel order, while Flysky uses AETR, and neither radio has the ability to change or remap the channel order. So much for that idea. Fun to learn how to do this on my own and achieve success, albeit partial.

I've been looking at the example for building a wireless buddy box, and I do have a spare Turnigy/Flysky receiver that outputs CPPM that I could use. Main question is: will I run into the same issue with the channel order, as the Flysky RX will still output AETR? If so I may have to abandon this idea of buddy boxing these two radios together. On the other hand, it may give me one more reason to upgrade to an OpenTX radio!

 

[FDS]

18650 laptop cells are LiCo, just protected LiCo. Still a lithium chemistry and a volatile one. LiMn (IMR) is less volatile as are the high drain type Lithium Ion power tool cells.
Thanks for the extra info @pressalltheknobs, there’s some good advice on that thread. That’s ridiculous that the standard QX7 doesn’t have the same charge port as the S. Lots more stuff to consider.
I hadn’t considered the channel outputs for buddy boxing. Let’s see if someone smart can solve that!

 

[PsyBorg]

@pressalltheknobs I added the m9s to my X9d+ and noticed an amzing jump in performance and accuracy.

It might not make much difference on fixed wing with servos and even less if they use cheap and sloppy servos.On a quad there is a huge difference.

As far as the hall sensors having issues with temps and humidity. I fly in temps below freezing at times out in snow or in summer with temps in the 90s with 60%+ humidity. Never had a glitch.

I just set up a new quad two days ago and the readings on channel centers are rock solid at 1500. My gimballs are ~ 2 years old now and get used nearly every day for at least an hour between flying and sims.

They are actually one of the very few things I have owned that have not fallen prey to Bills Law so I gotta brag em up a bit hehe.

 

[Mad_Mechanic]

@FDS - to further clarify on the QX7 battery and charging, my understanding is is that neither the QX7 or the QX7S has a battery charging port.

The QX7 has a removable battery tray that accepts 6x AA batteries. This is seriously old school but for some people it might be nice as AA batteries are common. This also why the QX7 doesn't have a charger included.

The QX7S comes with a NiMh battery pack instead of the AA tray, this is why they also include a charger with the QX7S. However, my understanding is that you have to remove the battery from the transmitter to charge it.

Check out this review, scroll down to roughly halfway to see what talking about with the lack of a charging port on the QX7S.

https://oscarliang.com/frsky-taranis-qx7s/

 

[pressalltheknobs]

@FDS - to further clarify on the QX7 battery and charging, my understanding is is that neither the QX7 or the QX7S has a battery charging port.

The QX7 has a removable battery tray that accepts 6x AA batteries. This is seriously old school but for some people it might be nice as AA batteries are common. This also why the QX7 doesn't have a charger included.

The QX7S comes with a NiMh battery pack instead of the AA tray, this is why they also include a charger with the QX7S. However, my understanding is that you have to remove the battery from the transmitter to charge it.

Check out this review, scroll down to roughly halfway to see what talking about with the lack of a charging port on the QX7S.

https://oscarliang.com/frsky-taranis-qx7s/

You have old information. New stock Q-X7 and QX7S come with a charging port and the Q-X7 typically no longer ships with the AA tray. There is no charge circuit and you have to use an external charger (eg: as I linked above.) It is fairly new so, as I said, there may be old stock out there without it and QX7's that have battery trays included.

I'm not a fan of the way they did it. It has 3 recessed but exposed pins and they don't give you a cover. Exposed pins means there is a possibility for shorts. It seems to be a special connector so I'm not sure why they chose to use that one. Since the middle pin is reportedly not connected there does not seem to be any reason to have 3 pins either...bit of a debacle... still it is convenient not to have to open the case and you can always come up with some kind of cover yourself I suppose.

 

[pressalltheknobs]

@pressalltheknobs I added the m9s to my X9d+ and noticed an amzing jump in performance and accuracy.

It might not make much difference on fixed wing with servos and even less if they use cheap and sloppy servos.On a quad there is a huge difference.

As far as the hall sensors having issues with temps and humidity. I fly in temps below freezing at times out in snow or in summer with temps in the 90s with 60%+ humidity. Never had a glitch.

I just set up a new quad two days ago and the readings on channel centers are rock solid at 1500. My gimballs are ~ 2 years old now and get used nearly every day for at least an hour between flying and sims.

They are actually one of the very few things I have owned that have not fallen prey to Bills Law so I gotta brag em up a bit hehe.

Clearly you are not one of the "meh!" people then

 

[pressalltheknobs]

So I took on the challenge today of soldering together my own trainer cable to buddy box a Turnigy TGY-i6S (clone of the Flysky FS-i6S) to my old Spektrum DX6i. I was able to find out the respective pinouts for the PPM output and found some spare S-Video and mono 3.5mm audio cables to cut apart and splice together. Got everything nicely soldered together and heat shrink around all connections, and was pleased that the cable worked perfectly well once I plugged the two controllers together and flipped the Trainer switch on the Spektrum. Only problem was: Spektrum uses TAER for the channel order, while Flysky uses AETR, and neither radio has the ability to change or remap the channel order. So much for that idea. Fun to learn how to do this on my own and achieve success, albeit partial.

I've been looking at the example for building a wireless buddy box, and I do have a spare Turnigy/Flysky receiver that outputs CPPM that I could use. Main question is: will I run into the same issue with the channel order, as the Flysky RX will still output AETR? If so I may have to abandon this idea of buddy boxing these two radios together. On the other hand, it may give me one more reason to upgrade to an OpenTX radio!

You will have the same problem. PPM is necessarily in channel order. An RX will output its CPPM in the order sent to it.

 

[Mad_Mechanic]

@pressalltheknobs - thank you for correcting my post with newer/current information.

Perhaps you can answer a small question for me. The QX7S at release was advertised as having an improved power on/off button/feature wherein you have to hold the power button for 3 seconds to turn off the transmitter. This was an improvement as it helps to avoid accidentally turning off the transmitter while adjusting trims.

However, I've seen in a couple places that the 'stock' QX7 also has this 3-second hold to power off feature. So how do the new QX7 transmitters ship as far as this function? I can see the 3-second hold being a good idea for the reason mentioned.

 

[pressalltheknobs]

As far as I remember the QX7 has always had a delay for turning off so I don't think it was ever a special QX7S feature. The soft switch delay is a firmware controlled feature so there is no reason for the QX7S to be different.

As far as I know, the only QX7S exclusive feature over the Q-X7 is the bluetooth support since there is no installed bluetooth in the Q-X7 and it is not a user plugable spare part. Apart from that the QX7S value adds are the installed M7 gimbals, "better" switches, a battery and charger, the color scheme and may be a carry case.

Note: In OpenTX 2.2.2 (might have been 2.2.1) there is also a delay turning on as well as off. I think the main reason OpenTX implemented the power on delay is because it is possible to turn on the TX by flexing the case particularly if you have the neck strap balance bar installed so the delay makes this less likely. I can still turn my QX7 on that way so it is only a partial fix.

EDIT: forgot about the "better" switches...think they are "futaba-style" and internally slide rather than snap but that is based on hearsay and innuendo.

 

[Bricks]

OpenTX implemented the power on delay is because it is possible to turn on the TX by flexing the case particulary if you have the neck strap balance bar installed so the delay makes this less likely. I can still turn my QX7 on that way so it is only a partial fix.

Now that Is a well built sturdy transmitter I am surprised they have not fixed this on the production end.

 

[Mad_Mechanic]

Something else I discovered recently by following Enderwrath's first plane build thread. Enderwrath has a new QX7 but it has the pairs of switches above the gimbals angled like a QX7S.

His transmitter is clearly marked as a QX7 and not an S model. He bought it on Amazon.

I think whats going on here is that FrSky may be deciding to use the X7S shell on new production/delivery X7 models for parts commonality.

That's not meant to say that the switches themselves are the newer nicer switches that the X7S has, I'm sure the X7 still uses the cheaper switches.

 

[pressalltheknobs]

The QX7 started shipping with the angled switch block shortly after the Q-X7S was released.

You are right. The QX7S also adds "better" switches. I think they are "futaba-style" and slide internally rather than snap. I omitted that above.

 

[Mad_Mechanic]

@pressalltheknobs - Thank you for confirming my suspicions on the switch positioning. I didn't know that the X7 now comes with the upgraded switches, I was under the impression that the switches were still the old style.

So then really the only advantages on paper for the X7S is the hall effect (M7) gimbals as standard (easily upgraded on a stock X7), the wireless trainer link, bluetooth telemetry to FreeLink phone app and that the X7S ships with a case, battery, charger.

For me, the case is actually a detractor for the X7S because I already have a padded foam case I like to use for transmitters, so the bundled one would just gather dust/take up space.

The battery and charger is also somewhat of a detractor to me because I'm planning on building 18650 cell packs for a radio, so I don't need these items either. The fact that the X7 does not come with a battery+charger works out nicely for me in this instance.

Admittedly, my situation is not 'normal' as I suspect most people will appreciate a case and included battery+charger.

 

[pressalltheknobs]

OpenTX implemented the power on delay is because it is possible to turn on the TX by flexing the case particulary if you have the neck strap balance bar installed so the delay makes this less likely. I can still turn my QX7 on that way so it is only a partial fix.

Now that Is a well built sturdy transmitter I am surprised they have not fixed this on the production end.

It may have been. Mine is a first batch. The OpenTX "fix" may be to address shipped units. I should say not all units had the problem when it was first noticed and I haven't come across anyone complaining about it recently...just complaints the addition of the power on delay

 

[pressalltheknobs]

@pressalltheknobs - Thank you for confirming my suspicions on the switch positioning. I didn't know that the X7 now comes with the upgraded switches, I was under the impression that the switches were still the old style.

So then really the only advantages on paper for the X7S is the hall effect (M7) gimbals as standard (easily upgraded on a stock X7), the wireless trainer link, bluetooth telemetry to FreeLink phone app and that the X7S ships with a case, battery, charger.

For me, the case is actually a detractor for the X7S because I already have a padded foam case I like to use for transmitters, so the bundled one would just gather dust/take up space.

The battery and charger is also somewhat of a detractor to me because I'm planning on building 18650 cell packs for a radio, so I don't need these items either. The fact that the X7 does not come with a battery+charger works out nicely for me in this instance.

Admittedly, my situation is not 'normal' as I suspect most people will appreciate a case and included battery+charger.

Sorry typo. The QX7 doesn't have better switches. The QX7S does.

The M7s are a fairly easy upgrade. The switches less so...soldering required. The bluetooth might be possible but there is no plug in component as far as I am aware.

Yeah extra gear can be a good value if you don't have it or want a spare but can be a waste if you don't (unless you can sell it on)