Answer first: the CG500 is a plug-and-play Band 20 + Band 8 flagship repeater for 500 m² that repeats Band 20 at 800 MHz for O2, Vodafone and Three 4G data and Band 8 at 900 MHz for O2 and Vodafone 2G calls and SMS, with ≥60 dB uplink and ≥65 dB downlink gain, a flagship ≥20 dBm output about twice the power of a 17 dBm unit, a ≤5 dB noise figure, 500 m² of indoor space and 50 active sessions, and a high-gain Yagi already inside the full kit. The basic job needs a drill, screwdriver, spirit level and clips, finishes in 10 to 15 minutes, and can grow to three indoor antennas through a splitter when the outside donor reads between -70 and -90 dBm. Follow the numbered steps, keep donor and server 10 m apart, apply power last, and leave the Yagi bracket on the exposed ridge after the test.

CG500 Snapshot Before You Aim the Included Yagi

A short spec table keeps every number this guide relies on in one place. The CG500 repeats Band 20 4G and Band 8 calls, recovers a faint rural donor with ≥60 dB uplink and ≥65 dB downlink gain, and spreads a flagship ≥20 dBm field across the rated 500 m² for 50 phones, with the Yagi included rather than ordered separately.

Step 1: Read the Outdoor 4G Signal in dBm Before Choosing Yagi or Omni

A flagship repeater can only amplify the signal the outdoor antenna actually receives; brick, reinforced concrete, solid stone and a tiled roof hide the tower from a handheld phone. The pre-mount survey happens outside the house, not on the sofa, and it decides whether the included Yagi gets aimed or the 5 dBi omni sits in open sky.

The dBm ranges the CG500 expects at the outdoor antenna

A reading of -97 dBm on 4G reads as a healthy rooftop donor the ≥65 dB downlink gain and ≥20 dBm output turn into a usable indoor signal across two floors and outbuildings attached to the home. -105 dBm sits at the edge of the recommended band and still produces a stable session once the Yagi clears the wall, rendered stone and pitch-side shelter; this is exactly the donor the included high-gain Yagi was supplied to recover, rather than a paid add-on. -112 dBm on 4G is the practical antenna near ceiling: below it the LTE receiver loses the control channel, the phone falls back to a slower service or shows no service, and no booster manufacturer can pull a donor never received. The ≥60 dB uplink gain covers a weak outdoor antenna better than holding a phone to the glass, but it cannot invent a band the survey never picked up.

How to read dBm rather than bars in a home survey

Phone bars are subjective and differ between iPhone and Android; the dBm figure is the measurement the amplifier actually sees. On an iPhone, enter field-test mode from the dialer and watch the RSRP value while standing beside the house. On Android, use an engineering or network diagnostics menu, or a free field-test app that lists RSRP by band. Hold the phone away from your body, because a hand and head absorb 3 to 5 dB, and read on the side facing the nearest mast rather than the sheltered courtyard.

Where to survey: roadside, side wall, garden gable, layby

Stand on the road-facing side, the open garden side at the rear, and the far side of the driveway; record the reading for your own SIM and a household member on a different network, because the strongest combined spot decides the Yagi bearing. On a rural lane the open gable or ridge beside a hedge or barn; on a town house the hard street-facing wall beats the enclosed courtyard. If Band 20 reads -112 dBm at every position beside the house, the CG500 cannot manufacture that band inside, though it may still improve voice on the other network's service; re-check facing the proper mast rather than expecting the amplifier to close the gap.

Step 2: Aim the Included Yagi at One Clear Mast; Keep the Omni for Open Sky

The full kit ships both a 5 dBi omni and a high-gain Yagi, and choosing between them is the first mounting decision. The omni gathers signal equally from all horizontal directions and suits a town house where usable masts sit in several bearings; the Yagi focuses a narrow beam on one identified rural tower and recovers several decibels more where a single mast serves the valley.

When the included Yagi earns its place

Switch to the Yagi when the survey shows a single clearly identified mast, RSRP between -105 and -112 dBm on 4G, and no second useful tower nearby. Aim by walking the signal direction with the phone, peak the reading, then fix the boom at that compass bearing and a slight upward tilt for distance. Because the Yagi is already in the box, you do not pay for the aerial upgrade separately the way smaller models do; only the bracket and a short mast need fitting.

Ridge or gable: clear sky line over 3 to 5 metres height

Fix the Yagi 3 to 5 metres up on the exposed ridge or gable, a metre clear of roof rails, satellite dishes, vent pipes and the TV aerial, so its beam is not blocked by roof metal. On a tiled or slate roof the supplied bracket bolts to a chimney stack or fascia; on a flat roof the weighted base settles in clear air. Keep the boom level in azimuth and tilt gently upward; never aim at a town centre several valleys away, because a closer weaker tower beats a distant strong one through a ridge.

When the 5dBi omni remains the better fit

Where two or more masts appear in different bearings and the donor sits between -97 and -105 dBm on every side, the omni's all-round pattern wastes nothing and avoids needing a rotation. Fit it vertically on the roof edge or gable, never tilt it, because tilting an omni cancels part of its circular pattern. The Yagi stays packed for a future rural move rather than forcing a narrow beam at a town donor.

Step 3: Run the 10 m Outdoor Cable to BS and the 5 m Indoor Cable to MS

The CG500 ships two feeds for two jobs, and keeping them straight prevents feedback that shuts the amplifier down. The 10 m outdoor low-loss coax runs from the roof Yagi or omni down to the chassis BS (base station / donor) port; the 5 m indoor coax runs from the chassis MS (mobile station / server) port to the 3 dBi whip inside.

What each length does and where it routes

Clip the outdoor feed every 40 cm along the fascia, drop it through a purpose-made wall gland rather than a loose window gap, and seal the entry with exterior silicone so rain cannot chase the cable in. Keep bends gentle; a tight right-angle fold crushes the coax and costs decibels. The indoor 5 m feed reaches the central whip; a split system routed through the splitter uses extra runs to the second and third antennas, covered in Step 5.

Cable upgrades for a detached house with a distant chassis

If the chassis lives in a garage at the edge of a detached plot and the Yagi on the main roof sits beyond 10 m, replace the outdoor feed with the 20, 30, 40 or 50 m length rather than splicing two cables; every metre of coax costs signal, and joined sections invite water and mismatch. Keep the indoor whip feed short, because lengthening the server side also spends recovered power before it radiates.

Step 4: Match BS and MS Ports Before Any Power

The chassis labels BS and MS on their ports. BS stands for base station, the outdoor donor side facing the tower; MS stands for mobile station, the indoor server side facing the phones. Swapping the two creates a feedback loop between antennas that the automatic gain control treats as a dangerously loud signal and throttles back, leaving the home weaker than before.

Connect in this fixed order

First fit the roof Yagi or omni, second fix the whip indoors, third lay the 10 m outdoor coax from donor to BS, fourth lay the 5 m indoor coax from MS to whip, fifth confirm both labels match, and only then prepare power. A physical check before the adapter goes in avoids the common fault where the indoor whip feeds the donor port and the outdoor Yagi feeds the server port. On the split version, the splitter sits on the MS side after the chassis, never on the BS donor side, because splitting the faint incoming feed wastes recovery headroom.

Step 5: Hold the Two Antennas 10 m Apart and Split to a Third Indoor Whip

Minimum isolation keeps the donor antenna from hearing the server antenna directly, which causes oscillation and automatic shutback. The CG500 calls for a 10 m vertical separation: outdoor Yagi high on the ridge, indoor whip low in the central hall, with floors and walls between rather than facing across a window.

10 m vertical isolation and the alternative horizontal gap

On a two-storey detached home the ridge Yagi above and the ground-floor whip below already supplies the vertical gap; measure straight down through the floors rather than around the furniture. Where vertical separation falls short, place the Yagi at one end of the property and the whip at the far end on the same floor, giving roughly 10 m of horizontal distance with solid walls in between. Bringing the whip within 5 m of the Yagi, especially through a single glass pane, invites the AGC to mute the output.

Expanding to 3 indoor antennas through a splitter on a strong donor

The CG500 states plainly that coverage expands by adding an indoor antenna, splitter and cable when the outside signal is strong. This expansion only works on a donor between -70 and -90 dBm, because a weak donor cannot spare extra split loss; on a strong donor, fit a two-way or three-way splitter on the MS side, run extra coax to a second whip in the far bedroom and a third whip in the office, cafe counter or hotel lobby, and let the ≥20 dBm output feed all three. Each split divides the radiated field, and the flagship output's extra headroom absorbs that division better than a 17 dBm unit; add antennas only where a single whip leaves a dead corner rather than blanketing every room by default.

Step 6: Power-On Sequence, LEDs and the 3 to 5 Minute AGC Lock

Apply power last and let the automatic gain control settle before judging the result. Rushing the LED readout within the first 30 seconds shows transient levels that change as the unit locks the donor.

The fixed power-on order

Connect both antennas and both cables, confirm BS to outdoor and MS to indoor, then plug the 5 V DC UK adapter into the wall and last into the chassis. The LEDs light, the internal AGC listens for 3 to 5 minutes, backs off when the tower looms close and recovers when the donor fades, and only then holds a steady field. Never plug the adapter first and attach antennas live; the chassis can see an open port and push gain into nothing.

Reading the band LEDs after AGC settles

A steady green on the Band 20 channel means the 4G donor is recovered and repeating; a steady green on Band 8 means the 2G call layer is up. A blinking amber signals the AGC still balancing after a weather or traffic change; a red or unlit band means that layer is not being received at the Yagi, which points back to Step 1 rather than a chassis fault. Wait the full 5 minutes before concluding, because the rural donor swings between clouds and ridge reflection.

Step 7: Split 500 m² into Zones and Test 50 Users Before Leaving

The final check proves the rating across the rooms rather than at the chassis. Divide 500 m² into five zones: central hall, living and dining area, kitchen or office, master bedroom suite, and the far bedroom or annex. In each zone, place a phone on 4G, open a data session, and place or receive an ordinary O2 or Vodafone call.

Zone test for data, calls and concurrent users

Record the bar count and RSRP on each band in every zone, run a speed test on 4G, and keep a call open for 60 seconds to confirm no drop. To prove the 50-user rating, gather family members, staff or guests on a mix of O2, Vodafone and giffgaff SIMs, hold a spread of calls and browser sessions at once, and check that none collapses into a drop when the busiest zone loads. A single perfect test at the whip position proves nothing; the far corner at floor level beside the furniture is the honest measurement.

Where a zone still falls short

If one far bedroom stays weak on a strong donor, add the second whip through the splitter; if the office and cafe counter both need a field, add the third. If the donor itself reads -112 dBm everywhere, more indoor antennas cannot fix the missing layer, and the aimed Yagi or a commercial array becomes the honest answer.

The 10 to 15 Minute Basic Timeline and the Tools You Need

The single-whip setup finishes in 10 to 15 minutes with hand tools; the split-to-three-antenna version adds the cable runs.

Tools for the basic install

A 6 mm masonry bit for the ridge or gable bracket, a Phillips screwdriver, a spirit level, cable clips, exterior silicone for the gland, and a phone with a field-test or speed-test app cover the whole job. No soldering, no network configuration, and no account registration with the carrier; the unit works on the licensed bands in Ofcom's permitted class as supplied, and the Yagi arrives ready to aim rather than waiting on a separate aerial order.

Rural Weak-Signal Optimisation: Aim the Included Yagi Rather Than Ordering One

On a village lane where one mast sits at -105 to -112 dBm, the omni's all-round pattern spreads energy in every direction and underfeeds that one tower. The included high-gain Yagi focuses a narrow beam on the identified mast, recovers several decibels, and turns a marginal -108 dBm donor into a repeating signal the ≥20 dBm output can spread across 500 m². Because the full kit already contains it, there is no separate aerial upgrade payment or delivery wait.

Aiming method for the included Yagi

Identify the mast on a coverage map first, then walk the compass bearing on site while watching RSRP; peak the reading on 4G, tighten the boom, and check the Band 8 call layer too. A slight upward tilt clears intervening trees; re-check after rain or leaf fall, because wet foliage absorbs more than bare branches. Do not over-tighten the bracket on a windy ridge without securing the boom against sway.

Surge protection and long cable runs

A rooftop feed exposed to lightning paths benefits from the optional in-line protector on the BS side, and a chassis in a distant garage calls for the 20 to 50 m outdoor upgrade rather than a splice. Neither replaces a weak donor; they protect and carry what the survey found.

Honest Limits: What the CG500 Does Not Fix at 500 m²

Four boundaries stay fixed no matter how high the output. The CG500 tunes Band 20 and Band 8 only, so it does not repeat 3G Band 1 at 2100 MHz, does not repeat any 5G band, and does not convert 4G into 5G. EE 2G voice sits on Band 3 at 1800 MHz and is not carried, so an EE household gets boosted 4G data where reach applies but not a boosted EE circuit call. The rated space is 500 m² for a detached home, medium office or small hotel supporting 50 sessions; it does not blanket a separate farmyard, multiple buildings or an estate beyond the main roof, and a permanently sited multi-building space calls for a commercial array rather than more home output.

Article Keywords

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