# Improving RF signal strength emonTH emonTX **URL:** \ **Category:** Emoncms\ **Created:** [10 October 2017 11:53 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318 "2017-10-10T11:53:46Z")\ **Posts on this page:** 11\ **Page:** 2
**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\ **Post date:** [15 October 2017 21:50 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/21 "2017-10-15T21:50:52Z")
Take a look at the Sparkfun website. You can add a length of 50 Ω co-ax and terminate that at the ground plane, then the antenna length is ¼ λ from the ground plane. [https://learn.sparkfun.com/tutorials/rfm69hcw-hookup-guide](https://learn.sparkfun.com/tutorials/rfm69hcw-hookup-guide) ---
**Author:** ![Paul](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/paul/32/28_2.png) [@Paul](https://community.openenergymonitor.org/u/Paul)\ **Post date:** [15 October 2017 22:06 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/22 "2017-10-15T22:06:11Z")
Oooh, I never even considered a dipole Robert… Paul ---
**Author:** ![borpin](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/borpin/32/193_2.png) [@borpin](https://community.openenergymonitor.org/u/borpin)\ **Post date:** [17 October 2017 20:22 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/23 "2017-10-17T20:22:03Z")
> [@Paul](#): > > I think that I gave details for the 433MHz antenna in a post above Ah yes, Sorry missed that for 433MHz. Yes I have a TX but I was thinking more of the base station RFMPi board. This is currently mounted on a Orange Pi Zero so a fixed antenna would not be an issue. I don’t think I need to go to a ground plane as well. ---
**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\ **Post date:** [17 October 2017 20:38 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/24 "2017-10-17T20:38:54Z")
The ground plane will help at both transmitting and receiving ends of the link. ---
**Author:** ![borpin](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/borpin/32/193_2.png) [@borpin](https://community.openenergymonitor.org/u/borpin)\ **Post date:** [17 October 2017 20:45 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/25 "2017-10-17T20:45:57Z")
> [@Robert.Wall](#): > > The ground plane will help at both transmitting and receiving ends of the link. Hi Robert, yes I get that. I just do not need that much improvement. The solid antenna on the receiving end should be just what I need. Also it is currently mounted on a wall which makes a ground plane a little tricky! ---
**Author:** ![pb66](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/pb66/32/27_2.png) [@pb66](https://community.openenergymonitor.org/u/pb66)\ **Post date:** [17 October 2017 21:52 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/26 "2017-10-17T21:52:03Z")
> [@borpin](#): > > Also it is currently mounted on a wall which makes a ground plane a little tricky! Adding a second wire of the same length to a gnd track near the existing antenna wire would work really well as a dipole. I had massive gains when I played with this on a JeeLink a couple of years back, a few days ago I went to add a link to a previous thread here as I had posted a picture back then but the pic’s no longer attached ([“weak signal?”](https://openenergymonitor.org/forum-archive/node/11110.html) on old forum), but I’ve just found a local copy. ![20150812_162743](https://community.openenergymonitor.org/uploads/default/original/2X/c/c86a33dcc96c63de95fae80b37bf35f1a68103a7.jpg) It’s just simple single solid core bread-boarding link wire, I have since rolled this method out on most of my emonTH’s, and rfm2pi’s with great results. plus the wires are thin enough to be discrete, especially when the wires can also be color coded to their surroundings too. I’ve also discovered that the antenna wire and ground plane wire are not that fussy about positioning, I have one rfm2pi on a Pi in a small case and both wires are coiled inside, one above and one below the board and even that gives better reception than the original multi-core antenna wire without a ground plane. ---
**Author:** ![Paul](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/paul/32/28_2.png) [@Paul](https://community.openenergymonitor.org/u/Paul)\ **Post date:** [17 October 2017 22:24 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/27 "2017-10-17T22:24:19Z")
I’d read about ‘coiling’ antennas elsewhere, but dismissed it as I couldn’t reconcile the supporting theory… …but it’s many years since I studied RF, and I’ve forgot more than I learnt! Paul ---
**Author:** ![pb66](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/pb66/32/27_2.png) [@pb66](https://community.openenergymonitor.org/u/pb66)\ **Post date:** [17 October 2017 22:32 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/28 "2017-10-17T22:32:09Z")
Oh no, I wasn’t suggesting I had done anything technically advanced, quite the opposite, I was just saying l’ve “tucked the wires away” rather than having the antenna and ground wires fully extended in opposing directions, and still getting good results. ---
**Author:** ![Bill.Thomson](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/bill.thomson/32/1834_2.png) [@Bill.Thomson](https://community.openenergymonitor.org/u/Bill.Thomson)\ **Post date:** [15 February 2018 16:22 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/29 "2018-02-15T16:22:01Z")
> [@Jon](#): > > A ⅝ wave might help with a good ground plane. The only “gotcha” here is a 5/8th wave antenna needs a matching section at the feedpoint. e.g. a tapped coil. ---
**Author:** ![Bill.Thomson](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/bill.thomson/32/1834_2.png) [@Bill.Thomson](https://community.openenergymonitor.org/u/Bill.Thomson)\ **Post date:** [25 December 2018 02:52 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/30 "2018-12-25T02:52:46Z")
Found some video clips I’d forgotten I made. The ground plane doesn’t necessarily need to be _metallic,_ just _conductive._ As can be seen in the first video clip below, an anti-static bag works quite well. [https://community.openenergymonitor.org/uploads/default/original/2X/f/fd924e64c7be754686009b40c85b44fdebc5aec7.mp4](https://community.openenergymonitor.org/uploads/default/original/2X/f/fd924e64c7be754686009b40c85b44fdebc5aec7.mp4) * * * In this clip, we see that it works even if the ground plane is simply _adjacent_ to the Pi vice underneath it. [https://community.openenergymonitor.org/uploads/default/original/2X/f/f782eebf62a44f1fa0bb77537de131d227bc8c46.mp4](https://community.openenergymonitor.org/uploads/default/original/2X/f/f782eebf62a44f1fa0bb77537de131d227bc8c46.mp4) ---
**Author:** ![dmajwool](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/d/7ba0ec/32.png) [@dmajwool](https://community.openenergymonitor.org/u/dmajwool)\ **Post date:** [19 October 2026 07:20 UTC](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318/31 "2026-10-19T07:20:29Z")
Thanks for the above suggestions. My emonPi2 was bought as a level3 heat pump monitor and is installed screwed to a wall near my (recently rebuilt) consumer unit enclosures in my attached garage. I have an emonTH in my greenhouse about 45 metres away and I was pleasantly surprised that this picked up OK when I installed it 4 months ago in the summer. For whatever reason, now in October the reception has recently become very intermittent. I’ve unscrewed the stock antenna from the emonPi2 and attached a 10metre coax and a new antenna inside the garage window that has line-of-sight to the greenhouse. Reception is now very good to the greenhouse emonTH and also the emonTH in the middle of the house 🙂 > **[BOOBRIE 433MHz Antenna with Bracket 5 dBi Garage Door Gate Small External...](https://www.amazon.co.uk/BOOBRIE-Antenna-External-Omni-Directional-LiftMaster/dp/B0GS1QL24P)** > > BOOBRIE 433MHz Antenna with Bracket 5 dBi Garage Door Gate Small External Antenna Omni-Directional SMA Male & F-Type Adapter for GTO Mighty Mule LiftMaster Ghost Gate Door Opener Alarm System【Enhanced 433MHz Signal & Extended Range】Operating at... > **[10M SMA Male to Female Extension Cable WiFi Antenna RG174 Coaxial Cable | Low...](https://www.amazon.co.uk/Female-Extension-Cable-Antenna-Coaxial/dp/B0H6X5DCW2)** > > Stamlyn 10M SMA WiFi Antenna Extension CableThe Stamlyn SMA WiFi Antenna Extension Cable is designed to improve wireless signal flexibility by extending antenna placement for better reception and coverage. Built with a long-lasitng RG174 coaxial... [Previous page](https://community.openenergymonitor.org/t/improving-rf-signal-strength-emonth-emontx/5318.md?page=1)