Installing a module from a DX-5 - Antenna options?

[DudeInMyrtleBeach]

I'm getting ready to disassemble my dx5 and take the module out to be installed as an internal module in my 9x. Every one of the specktrum mods I see has the antenna being moved with the module. Why? This is all 2.4 so it makes no sense to me. I see it being referred to as 'the DSMX antenna' and this makes even less sense.

I'm intimately familiar with both FHSS and DSSS systems. Can someone tell me why I can't just disconnect the existing antenna and use it? Is it a gain issue or poor design?

Thanks!

[Kilrah]

Can someone tell me why I can't just disconnect the existing antenna and use it? Is it a gain issue or poor design?

Simply because the existing antenna of the 9x has no connector, its cable is soldered directly to the board in the module case.
The Spektrum module however has an u.FL connector. Removing the module's connector to solder the antenna to it is kind of risky, and installing a matching connector on the 9x antenna is impossible without proper equipment.
So, to most people, the easiest is to either reuse the DX5's antenna and mount it on the 9x, or get an (RP)SMA-u.FL pigtail, drill a hole somewhere on the 9x case to install it and screw an antenna on there.

[DudeInMyrtleBeach]

Ah! That's an even better idea.. I've got a box of RPSMA pigtails in my garage. Thanks!

Last questions -- Even though I can solder well, I'm no EE - since the mod calls for a diode, can I use an LED instead? I have a box of those too,lol. If I rob the 3.3v regulator off of the dx5 can I still use it with my sim? Is the regulator a required part to function period, or just for the radio module.

Thanks for the help!!

[Kilrah]

No, a LED won't work, voltage drop is too big.
The regulator powers the whole radio, so if you take it away the donor becomes useless.

[DudeInMyrtleBeach]

Thank you for your help. I'm going to take a step back from this until I get a ubec and the correct diodes then. Thanks again.

[pmullen503]

When I did mine, I used the base of the 9x's antenna to fit the antenna from my HP6DSM donor radio. The combination of the HP6DSM antenna on the 9x base fits the 9x's case perfectly using the stock mounting screw.

Don't know if it will work as nicely with the DX5, but it might be worth a look: 9x gets a Spektrum module

[mbanzi]

This is buried a little in the Wiki, but I used a replacement FrSky module antenna lead & antenna which I got from Aloft Hobbies for $5, in a old FlySky module case:

9x_Full_Mod_DSM2/X