A repeater in a conduit body
A low-profile solar repeater built inside a 1" Type C conduit body, the straight-through fitting with a removable cover that electricians use to pull wire along a run of conduit. It is cheap, made to live outdoors, and just big enough for an 18650 holder with the board mounted on it, all fixed to the cover so the electronics lift out in one piece. PVC conduit, a coupling and a cap complete the body, an N-type connector takes the antenna, and a waterproof vent lets it breathe.
What each variant costs
Pick the variant that fits the site, then jump to its parts list and photos.
| Build | Base | + 5 dBiw/ 5 dBi antenna | + 5.8 dBiw/ 5.8 dBi antenna |
|---|---|---|---|
| 1W RAK build30 dBm | $98.20 | $106.21 | $115.55 |
| Heltec 4.3 build28 dBm | $77.20 | $85.21 | $94.55 |
| Energy efficient build22 dBm | $46.99 | $55.00 | $64.34 |
Costs include the enclosure but not mounting hardware. Prices are what the parts cost when they were bought and will drift as sellers change them. Bulk packs are costed by the share one build uses, so a first build costs more up front and leaves spares for the next. Some part links are affiliate links, which may earn a commission at no extra cost to you.
The enclosure
Every variant starts from the same enclosure, at $16.28 a build.
| Part | Qty | Price | Cost |
|---|---|---|---|
| 1" Type C conduit body (4 pack) (opens in a new tab) | 1 of 4 | $18.99 | $4.75 |
| 1" PVC conduit pipe | 1 ft of 10 ft | $11.00 | $1.10 |
| 1" conduit coupling | 1 | $0.81 | $0.81 |
| 1" conduit cap | 1 | $2.28 | $2.28 |
| 18650 2-cell battery holder (6 pack) (opens in a new tab) | 1 of 6 | $9.19 | $1.53 |
| N-type female to IPX connector, 20 cm (opens in a new tab) | 1 | $3.35 | $3.35 |
| OD 8 × M6 stainless steel spacer (10 pack) (opens in a new tab) | 2 of 10 | $2.24 | $0.45 |
| 5 × 20 mm 1.25A fuse holder (5 pack) (opens in a new tab)A 2A fuse is the better choice for 1W Rak Build. | 1 of 5 | $6.12 | $1.22 |
| Waterproof air vent M12 × 1.5 (10 pack) (opens in a new tab) | 2 of 10 | $3.94 | $0.79 |
| Total | $16.28 | ||
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(opens full size in a new tab)1W RAK build
30 dBm transmit$98.20 with enclosure
The long-range option. A RAK WisBlock with the 1W booster, two 18650 cells and an MPPT charge controller, with a 5W panel on a ball head so it can be aimed at the sun.
Pictured with the 5.8 dBi antenna, which brings it to $115.55.
| Part | Qty | Price | Cost |
|---|---|---|---|
| RAKwireless 1W booster kit | 1 | $45.00 | $45.00 |
| 5V 5W USB solar panel (opens in a new tab)A 4-pack brings it to about $10 a panel. (opens in a new tab) | 1 | $16.99 | $16.99 |
| Aluminum alloy mini ball head (opens in a new tab) | 1 | $1.89 | $1.89 |
| PG7 nylon cable gland (10 pack) (opens in a new tab) | 1 of 10 | $2.20 | $0.22 |
| Metal double male 1/4" screw (5 pack) (opens in a new tab)One end cut off with a Dremel; there may be a ready-made alternative. | 1 of 5 | $3.20 | $0.64 |
| Samsung 35E 18650 battery (opens in a new tab) | 2 | $7.00 | $14.00 |
| CN3791 MPPT solar charge controller (opens in a new tab)A CN3065 also works and brings this to $0.64. (opens in a new tab) | 1 | $3.18 | $3.18 |
| Total | $81.92 | ||
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(opens full size in a new tab)Heltec 4.3 build
28 dBm transmit$77.20 with enclosure
The same enclosure and power system as the 1W build, around a Heltec V4.3 without the OLED screen. A little less transmit power for a good deal less money.
| Part | Qty | Price | Cost |
|---|---|---|---|
| Heltec V4.3 (no OLED) | 1 | $24.00 | $24.00 |
| 5V 5W USB solar panel (opens in a new tab)A 4-pack brings it to about $10 a panel. (opens in a new tab) | 1 | $16.99 | $16.99 |
| Samsung 35E 18650 battery (opens in a new tab) | 2 | $7.00 | $14.00 |
| Metal double male 1/4" screw (5 pack) (opens in a new tab)One end cut off with a Dremel; there may be a ready-made alternative. | 1 of 5 | $3.20 | $0.64 |
| Aluminum alloy mini ball head (opens in a new tab) | 1 | $1.89 | $1.89 |
| PG7 nylon cable gland (10 pack) (opens in a new tab) | 1 of 10 | $2.20 | $0.22 |
| CN3791 MPPT solar charge controller (opens in a new tab)A CN3065 also works and brings this to $0.64. (opens in a new tab) | 1 | $3.18 | $3.18 |
| Total | $60.92 | ||
No photos of this variant yet.
Energy efficient build
22 dBm transmit$46.99 with enclosure
The cheapest and smallest. A XIAO nRF52840 with a Wio-SX1262 sips so little power that one 18650, a TP4056 charger and three small panels fixed flat to the enclosure keep it running, with no ball head or large panel to catch the wind.
Pictured with the 5 dBi antenna, which brings it to $55.00.
| Part | Qty | Price | Cost |
|---|---|---|---|
| TP4056 lithium battery charger (20 pack) (opens in a new tab) | 1 of 20 | $2.59 | $0.13 |
| Samsung 35E 18650 battery (opens in a new tab) | 1 | $7.00 | $7.00 |
| 1N5817 Schottky rectifier diode (100 pack) (opens in a new tab)One in the + lead of each solar panel, to stop backflow. | 3 of 100 | $3.90 | $0.12 |
| XIAO nRF52840 & Wio-SX1262 (opens in a new tab) | 1 | $14.06 | $14.06 |
| 5V 200 mA solar panel, 130 × 60 mm (opens in a new tab) | 2 | $3.60 | $7.20 |
| 5.5V 160 mA solar panel, 140 × 45 mm (opens in a new tab) | 1 | $2.20 | $2.20 |
| Total | $30.71 | ||
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(opens full size in a new tab)Antennas and mounts
Not included in the base cost. Each build has an N-type connector, so any 915 MHz antenna with an N-type plug will fit; these are the two the builds above use.
Antennas
| Part | Qty | Price | Cost |
|---|---|---|---|
| 915 MHz 5 dBi LoRa antenna (opens in a new tab) | 1 | $8.01 | $8.01 |
| 915 MHz 5.8 dBi fiberglass antenna, 35 cm (opens in a new tab) | 1 | $17.35 | $17.35 |
Mount options
| Part | Qty | Price | Cost |
|---|---|---|---|
| Countersunk magnet 25 × 7 − 5.5 mm (10 pack) (opens in a new tab) | 2 of 10 | $12.50 | $2.50 |