Topic: External antenna for the 2902 array

[WA4OPQ]

Here is the method I use for an external antenna on the 2902 array. I've done two so far and starting on my third.

For tools you will need a good soldering iron (not soldering gun), solder wick, small screwdrivers, needle nose pliers and flush cutters. You will also need a Dremel moto tool or equivalent and a crescent wrench.

You will be using the solder wick to remove solder from the antenna hole. If you have not previously done this then this is not a good time to learn. Please find someone near you to help with your soldering.

Also used are about 12.5 inches of RG-174 miniature coax and a single hole N connector. I will provide Amazon part numbers at the conclusion of this instruction.

Our first step is disassembly. Remove the wind vane and cups. Keep all your parts and screws in plastic bags.
In this photo are four screw holes on right. They use different phillips screws, I believe they are called #1 and #2. Before you start make sure you have the correct screwdrivers. Then remove all the phillips screws and the wind end pieces (two small connectors). Also remove the rain cup and temp assembly; It requires cutting the rubber shrink tube and very carefully pulling out the connector.

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[WA4OPQ]

Once it's open here's what you'll see. Carefully remove the connector to the battery compartment first. Then remove three odd phillips screws to dislodge the circuit board.

Add solder to the point where the antenna attaches, heat it and gently wiggle the antenna loose using needle nose pliers. three hands would be helpful, too.

Use an x-acto knife to remove the green conformal coating for a solder pad for the coax braid.

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[WA4OPQ]

Here is the antenna for size.

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[WA4OPQ]

There is a rectangular plastic box in this area. It must be cut and ground down with the moto-tool for clearance.

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[WA4OPQ]

Here is generally how I routed the coax, keeping a loop so that it can be opened easily. Also note the small rectangular notch I cut in the plastic wall for the coax to go through.

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[WA4OPQ]

Not shown is cleaning the solder out of the hole that the antenna was in.
Once the hole is open the coax is stripped back. The center conductor is soldered where the antenna formerly was and the outer braid is twisted and soldered to the ground pad we just made.

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[WA4OPQ]

Here's the N connector. The brass center conductor is too long so we cut off half of it with the Dremel cutting wheel.

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[WA4OPQ]

The N connector is mounted midway between the two screw bosses. I used a versa-bit to drill it and the Dremel to clear off a ridge. Make sure you tighten it well; on my first one I didn't and when I was on top of a ladder and tightened the coax connector it spun and shorted.

I didn't get a photo of the completed and soldered setup. This photo is a preliminary test and is sloppy and probably shorted out.

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[WA4OPQ]

We're almost done.
Now for careful reassembly. The coax has to nudged so it's inside the circuit board compartment, and inside of the wall thing. It took me about five times to get it all nicely done.
And be sure to reconnect the battery connector.

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[WA4OPQ]

Here's how it looks completed.
Cross your fingers and test it.
Run a coax jumper to your antenna and you're all done.

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[WA4OPQ]

connector  https://www.amazon.com/gp/product/B071J2ZCHV
RG-174 coax https://www.amazon.com/wlaniot-RG174-Coaxial-Rg-174-Meters/dp/B07L67M9YT
Gain antenna https://www.amazon.com/gp/product/B014CU9JYQ
coax jumper https://www.amazon.com/XRDS-RF-Extension-Connector-Coaxial-Antenna/dp/B07V5YQVZB
You'll need this https://www.amazon.com/gp/product/B018DLMHFI

[WA4OPQ]

As a PS:

I didn't use a gain external antenna. In my case the ObserverIP, GW1000 and router are inside of a large metal barn. When the doors are closed the signal goes away. So I ran 30' of coax from the 2902 array to a hole drilled through the wall. I made a 915 MHz dipole antenna for inside out of a popsicle stick.

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[bvstation]

Thats a pretty nice walk thru.
My question is can I just solder the cable semi conductor directly to the antenna and leave it there?
I wouldn't think this would hurt anything if I did that way I wouldn't need to pull it off.

[WA4OPQ]

From an electrical standpoint you'd have two antennas, with each getting half the power.
So you'd have a less effective external antenna.

[bvstation]

From an electrical standpoint you'd have two antennas, with each getting half the power.
So you'd have a less effective external antenna.

Ok I'm doing this with yagi antenna also and much like what the other guy did. They attached it to the bottom there and it seems to have worked so that is why I'm asking to avoid soldering the antenna out completely.
Makes sense about the power though.

[bvstation]

Ok I did what you put here minus how the wiring was at first and how it was channeled. Had difficulty getting the station closed up but managed.
Just heated the spot for antenna, it fell out and put in the wire/cleaned off place for the braid. Went from 0 bars to 4 solid and all good using the yagi setup.
Thanks for the instructions.

[WA4OPQ]

I'm glad it worked well for you.
Yeah, it took me about five times putting it back together to get everything to fit right.

[hdtvluvr]

So with the Yagi, what is the new transmission distance? And how many walls (and construction type) in that distance?

[bvstation]

So with the Yagi, what is the new transmission distance? And how many walls (and construction type) in that distance?

I'm going every bit of 100feet thru 2-3 walls and thicker windows on that end. Full bars with that.
Construction type are double pane glass windows, 100 year old walls plaster and so on lol so yeah should be a lot there.

[WA4OPQ]

So with the Yagi, what is the new transmission distance? And how many walls (and construction type) in that distance?

The yagi antenna should give you about 10 times the signal strength, which should mean 3 to 5 times the distance.
But many variables can change it, such as metal, walls, concrete, etc.

[hdtvluvr]

I'm looking at 270 ft through 1 outside wall (wood stud, plywood & vinyl sided) to the first display and then the other display would be about 310 ft through the same outside wall and then 2 sheetrock walls.   Do you think this mod would do that?

[WA4OPQ]

I'm looking at 270 ft through 1 outside wall (wood stud, plywood & vinyl sided) to the first display and then the other display would be about 310 ft through the same outside wall and then 2 sheetrock walls.   Do you think this mod would do that?

I think it would. But there are no guarantees.

[bvstation]

I'm looking at 270 ft through 1 outside wall (wood stud, plywood & vinyl sided) to the first display and then the other display would be about 310 ft through the same outside wall and then 2 sheetrock walls.   Do you think this mod would do that?

Ehh it will be tight. certainly better than the stock antenna

[hdtvluvr]

bvstation

Which Yagi did you use? 
XHTECH 11dBi 824-960MHz GSM CDMA Yagi Antenna Outdoor
https://www.amazon.com/gp/product/B014CU9JYQ/ref=ox_sc_saved_title_1?smid=A27P16HLMP5BKI&psc=1
or
Phonetone 7/9dbi Outdoor Directional Yagi 698-960/1710-2700Mhz GSM Outdoor Antenna
https://www.amazon.com/Phonetone-Outdoor-Directional-1710-2700Mhz-Connector/dp/B00EC804SO/ref=pd_ybh_a_5?_encoding=UTF8&psc=1&refRID=7TQB73HD0ZDS9TWTNKCE

or something else?

[bvstation]

I got that 2nd one
https://smile.amazon.com/gp/product/B00EC804SO/ref=ppx_yo_dt_b_asin_title_o07_s01?ie=UTF8&psc=1

also used this
https://smile.amazon.com/gp/product/B07V2VFHS9/ref=ppx_yo_dt_b_asin_title_o07_s01?ie=UTF8&psc=1

and one of these
https://smile.amazon.com/gp/product/B07MJQWH8S/ref=ppx_yo_dt_b_asin_title_o07_s01?ie=UTF8&psc=1

It was a rather simple thing to do...my biggest issue is packing the wire inside to close the thing up. Its still somewhat 'swollen' on one end. If I redo it for whatever reason or get a wild hair to redo it later I'll cut that wire down inside by a few inches vs 5 inches I think I left inside. Not a big deal it closed up ok and I'm happy.