Jumper T8SG - First TX stock running on Deviation

vlad_vy wrote: dc59, what do you think about LCD contrast? Is it enough? Now contrast can be changed from 0 to 10 (Tx settings), but LCD chip can use values from 0 to 63.

I think 0 to 10 contrast setting is good enough, but it's backlight design is bad, you can find all my LCD pictures have 2 light spot at bottom side, light uniformity is very poor!

Is this size comparison real? Quite a big radio.

img09.banggood.com/forum_images/20170906...0906035921_53229.jpg

Wonder if they would consider selling just the board and screen for those of us wanting to make an ultimate TX out of older technology or those that want to tinker with size and layout formats

Watching this thread with much interest

It is the same size as the little Devos, i.E. the 7e, so it is rather small.

No idea if the other TXs on that picture are as small as that.

dc59 wrote: #1 TX is final version of T8SG , #2 & #3 are different model and different price ..............
But I don't thing Banggood can sale final version of T8SG in this month because hall sensor gimbal has not been produced and tested yet.

Thanks for clarifying, dc59. If Jumper can give us a Deviation-based, multi-protocol, compact TX with hall sensor gimbals for the pre-order price of $90-100, that will be incredible!

ajtank wrote: It is great to have a transmitter customized for Deviation. Whilst every parent got different expectations for a new born baby, all thoughts must be realistic and justified.

$99 for Jumper's existing version seems on the high side to me when I look at the price for Devo 7e and Devo 10. Recently the legendary Frsky Taranis transmitter has also hit the $170 price point. Let's see how Jumper can emerge successfully from the market.

ajtank: Well said about parents' expectations for a new baby.

As for price, remember that the T8SG will come with four (4!) RF modules built in! While Devo 7e is very affordable, you have to spend $40 extra for a 4-in-1 RF module, plus more for upgrades like 3-position switches and removable antenna. So I think the current $100 price for the T8SG remains quite attractive, especially if it ships with improved gimbals.

aMax wrote: Is this size comparison real? Quite a big radio.

img09.banggood.com/forum_images/20170906...0906035921_53229.jpg

aMax: That size comparison is an inaccurate photo montage. The picture below offers a better comparison with the compact Devo 7e, which is much smaller than Taranis X9D+ and QX7.

Ok, this won't work. Both display drivers only allow write access when connected via SPI...We have to find something else for this to work.

Querying the memory chip seems a possibility, as probably a devo7e-256 won't change his flash memory. Or we stick with the simplest option and define display inversion in hardware.ini, as this file has to be custom for the tx anyways, as it needs to be modified from it's default values to define switch setup and 4-in-1 connections.

Moeder wrote: I was scanning through the data sheets for both UC1705 and NT7538 and noticed, that the behavior of the status register "enable" (or ON/OFF) when read out seems inverted between the two drivers. This could be used to differentiate between the two displays.

aMax wrote: Is this size comparison real? Quite a big radio.

img09.banggood.com/forum_images/20170906...0906035921_53229.jpg

Compare to Frsky QX7 & X9D+ :

Jumper want to use unused MCU pin to control 4-in-1 module antenna switch (PE1/PE2) ,
they think it would be more stable for all system , they can change PCB layout no problem ,
but it's need firmware support !
BTW, Which pins are suitable for PE1/PE2 ? any suggestion ?

Does the 4-in-1 module they are using have an onboard MCU that could handle that via the Chip Select, or don't they have access to the module production? Or doesn't the onboard MCU have enough spare pins?

I don't know what the chip select lines look like (never installed a module), but I'm guessing it could also be done with a simple logic switch chip driven by these lines?

status	PE1	PE2
A7105 RF signal to antenna	0	0
CC2500 RF signal to antenna	0	1
NRF24L01 RF signal to antenna	1	0
CYRF6936 RF signal to antenna	1	1

The above was found as a reference in the standalone multimodule, here's an example:
Multiprotocol module (Flysky Frsky Devo DSM2)
That was the only place I found that referenced seperate controls for PE1 / PE2, so maybe they are using a partial board from this? Actually, the pins on the shielded module part look identical to the ones shown on the TX board here... vlad, any info on which logic chip is used?
EDIT: OK looks like they both use the same shielded module, but the logic chip is external to it, so would just need to be added to the TX board

have I proven my worth yet for a freebie?

The chip is actually a STC MCU determining the traffic of the RF switch.

Damned BG just canceled the order I had saying they can ship it to France ;...