X-10 Patch Antenna Connection Questions

[PilotSmith 0]

I am planning to build the GP PATCH ANTENNA for my X10 receiver. The plans call for a connector on the patch antenna that you screw in the antenna lead. However, there will be no connector on the X-10 lead once I take off the original antenna. Should I just solder the existing lead to the patch antenna. (Shielded part soldered to the reflector and inside part of the cable soldered to the element?) Should I solder a male SMA connector to the lead to be able to screw onto the GP Patch? One way better than the other?

Also, I want to modify the X10 transmitter antenna. I saw the RC-CAM4 PROJECT

Chapter IV: Strip Tease antenna ( http://www.rc-cam.com/rc-cam4b.htm#rc-cam4_top ) and one that is a little more complex to build from YB2Normal ( http://www.yb2normal.com/antenna2.html ). Can someone tell me if there would be much to gain by using the YB2Normal over the simpler to build Strip Tease unit?

And finally, I can get reasonable quality video with the stock X10 setup now (when close to the receiver) if I am off the throttle. But under power there are horizontal skinny white lines. I am running a brushless motor. Not sure if this is related to vibration or noise from power lines to the motor. Any ideas? Thanks!

Remembered one more thing. I am running the X10 transmitter off of a 3 cell LiPo that powers everthing else on the plane (9-12v). I am getting a 4 cell pack and wondering if it can handle voltage over 12v???

Edited February 16, 2005 by PilotSmith

[Mr.RC-Cam 121]

Should I just solder the existing lead to the patch antenna.

Sure. Try to shorten the existing coax (it is very RF lossy).

Can someone tell me if there would be much to gain by using the YB2Normal over the simpler to build Strip Tease unit?

The groundplane shown by YB2normal has more gain.

But under power there are horizontal skinny white lines. I am running a brushless motor. Not sure if this is related to vibration or noise from power lines to the motor. Any ideas?

You mentioned that your camera gear shares power with the R/C equipment and the motor. This is a tough configuration to get to work well -- the noise is motor ripple.

I am getting a 4 cell pack and wondering if it can handle voltage over 12v???

The existing X10 AC power supplies are not regulated and exceed 12V by a wide margin. So, my gut feeling is that the X10 Cam should be able to handle a 4-cell LiPO pack. It is internally Vreg'd, so worse that is expected to happen is that the Vreg will run hot and shut down. However, if you have added a 5V CCD camera then a separate Vreg will be required.

[PilotSmith 0]

I have a few small cell phone lipo cells. I'll make a 2 cell pack from them to drive the transmitter/camera to see if that eliminates the interference. Thanks for the info!

[Mr.RC-Cam 121]

A 2-cell LiPO might not work well. The X10 Cam requires at least 8.8VDC or performance may suffer.

[PilotSmith 0]

Do you need special solder for tin??? I tried and tried and could not get it to stick to the tin. Used 40w iron and then 150w gun. After much frustration tried some plumbing solder instead of the regular rosin core solder for electronics and that seemed to work better but still doesn't look real good.

[Mr.RC-Cam 121]

Common tin solders very well using standard rosin core electronic solder. If your material cannot be attracted by a magnet, then it is aluminum.

[PilotSmith 0]

I feel so stupid - It must be aluminum as a magnet does not stick to it. I resoldered it using the plumbing solder and got what appears to be a good solid connection this time. So the question that now comes to mind is whether an aluminum GP Patch antenna is ok or if I should spend the big bucks and pick up a piece of roofing tin at Lowes to redo the antenna???

[PilotSmith 0]

In real world flying conditions, is there going to be a noticable difference from using the Strip Tease vs the YB2Normal antenna? And you are very right on the cam voltage. I tried running on a 2 cell LiPo pack and it didn't work at all.

[Mr.RC-Cam 121]

It is hard to say.

[PilotSmith 0]

Would you recommend that I redo the GP Patch Antenna with tin or the aluminum one I made by mistake should work fine? BTW, thanks for being so helpful and answering my 101 questions!

[Mr.RC-Cam 121]

I doubt you achieved a good solder connection to the aluminum. Also, a lot of heat was probably used to bond to the aluminum, so the coax's poly dielectric was surely damaged.

I suggest that you spend the $1.50 at Lowes and get the tin roof flashing. Be very careful when soldering so that the coax is not damaged. At microwave frequencies, everything matters.

[tomapowa 0]

To solder aluminum properly (i.e. the tabs on most LiPo batteries), you really need to use aluminum solder paste. Without this, your connections will look good until you put it under load. Check out:

http://www.solder-it.com/solderpaste.asp

The ALP-21 product is exactly what I use (found at discount store near me for $.99, I bought them all up as I assemble LiPo packs for my friends). This stuff actually contains aluminum solder and paste in a syringe. If you are lucky, you can now buy LiPo cells with tin tabs spot-welded onto the aluminum tabs (make soldering a breeze).

Edited February 20, 2005 by tomapowa