Every Group on Its Own Frequency

A university open day is the densest concurrent tour event most admissions teams ever run. Between nine and noon, twenty families may be walking the same campus: one group at the engineering lab, another in the library rare-words room, a third crossing the quad behind a student ambassador, all rotating through the same five stops on the same morning. The logistics staff already know the failure mode — a family catches half of another group's lecture drifting across the lawn, or a receiver handed out at check-in dies before the residence hall. A wireless guide system for campus tours exists to make each of those twenty groups acoustically invisible to its neighbours. This comparison runs three Richitek models against two Chinese specialists in exactly that discipline: YINGMI and Yiyouyou.

The trio is picked by role. The RC2408 is the channel-heavy congestion solver. The RC2468 is the featherweight ear-hook built for visitors who have never worn a tour device before. The RC2402 is the baseline fifty-channel kit that fills out a fleet at the lowest cost per unit. YINGMI approaches the same brief with CRC-encrypted digital transmission, while Yiyouyou leans on encrypted channels and receiver battery life measured in days. One side is a ten-model line with a shared chassis; the other, a specialist's answer to one question: how do you keep twenty concurrent groups from ever hearing each other?

RC2408: Eighty Channels for a Quad Full of Tours

The RC2408 earns its slot on the check-in table through channel arithmetic. It works in the licence-free 2403-2483 MHz band and carries eighty PLL-locked channels — thirty more than the line's standard fifty — precisely the headroom an open day needs when twenty tours launch within the same hour and the following weekend adds a graduation rehearsal on top. Ten milliwatts of output keeps each signal boxed around its own group, and the stated 1-200 metre working range covers a full quad circuit without repositioning. The transmitter weighs 59 g and runs ten hours from a 1500 mAh cell; receivers hold twenty hours on 1000 mAh, so a kit issued at 8:30 comes back after the last tour with charge to spare. The RC2408 product page publishes the full eighty-channel allocation plan.

RC2468: The 18-Gram Ear-Hook for First-Time Visitors

The RC2468 is the reception desk's best argument. Its receiver weighs 18 g in an ear-hook format — the lightest wearing experience in the entire Richitek line — and a family on a two-hour campus walk simply stops noticing it. The trade lives in the battery: the 300 mAh receiver cell delivers roughly eight hours, the shortest figure in this comparison, so fleet managers must run the charging case between the morning and afternoon waves rather than skipping it. The transmitter is standard spec — 59 g, ten hours, fifty channels, 10 mW. Charging runs through a USB port rated 5V/1A, and the ear-hook format keeps the unit visible on the ear, which quietly solves the "did you return your receiver?" problem at the exit desk. Full details sit on the RC2468 page.

RC2402: The Baseline Kit That Fills Out the Fleet

The RC2402 is the straightforward fifty-channel 2.4G standard build, and on a campus that runs one or two concurrent tours most weeks, it is all the machine the job needs. Receivers weigh 50 g and hold twenty hours from a 1000 mAh cell — a full admissions day, morning open house and afternoon departmental visits, on one charge. The transmitter matches the family chassis at 59 g and ten hours from 1500 mAh. Nothing here is exotic: PLL discipline across fifty channels, a 1-200 metre working range, a DC charging port shared with the rest of the non-Type-C fleet. Its role is volume — the units you buy in bulk so a surge of walk-in families never sends the check-in desk scrounging. The RC2402 page carries the channel and battery specifics for procurement.

How YINGMI and Yiyouyou Attack the Same Morning

YINGMI's E8 takes an encryption-first route. It transmits digitally in the 2.4 GHz band using 4GFSK modulation with CRC encryption, pairs a 16 g integrated ear-hook receiver with a "one main, two deputy" dual-speaker arrangement, and applies SOC-embedded digital noise reduction. The company markets a zero-interference track record across deployments of ten thousand to one hundred thousand units — a claim that maps directly onto the concurrent-group problem this article is about. Its L8 kit adds a full-function LCD, a 150 m-plus reception radius and eight to ten hours of battery life. Yiyouyou counters on endurance: the E519 is an 18 g neck-strap receiver with encrypted digital channels, stepless volume control and a published 33-100 hour battery figure, while the D300 ear-hook runs up to five days per charge with basic rain resistance. The brand's deployment list — the Terracotta Army, the Potala Palace, Gulangyu, Mount Emei — is a résumé built on exactly the high-volume, high-concurrency touring that this comparison borrows as its test bench.

⚖️ Encryption Versus Channel Discipline

The deepest difference here is how each camp prevents cross-talk. The Richitek trio separates groups the coordination way: every transmitter and receiver is PLL-locked to one of fifty or eighty assigned channels, and as long as no two groups share a number, they cannot hear each other — interference is avoided by management, not by mathematics. YINGMI and Yiyouyou instead encrypt the audio stream itself, so a co-channel collision degrades into noise, not another family's guide. Both approaches live lawfully inside the same licence-free 2.4 GHz spectrum. Encryption buys confidentiality and collision tolerance. Channel discipline buys simplicity, instant repairs when a unit drifts, and a channel plan every member of the check-in staff can read at a glance.

The Numbers Behind the Open Day

Read as a morning schedule, the table says: all three Richitek models hold a ten-hour transmitter standard and a 200-metre reach, the choice among them is channel headroom against receiver weight and battery, and the encrypted challengers compete on wearing comfort and, in Yiyouyou's case, receiver endurance figures the Richitek line does not attempt.

What the Trio Cannot Do Yet

Three limits deserve honesty. None of the three Richitek models encrypts its audio — group separation rests entirely on channel assignment, so a mis-assigned channel produces overlap in a way an encrypted system would not. The RC2468's eight-hour receiver is the shortest battery in the field, thin margin if the afternoon wave starts late, and it alone in the trio charges over USB rather than sharing the fleet's DC carts. Neither side publishes an ingress-protection rating — a real consideration in autumn drizzle — though Yiyouyou's D300 at least claims basic rain resistance. And YINGMI's "one main, two deputy" dual-speaker arrangement has no counterpart among the three review models; the line's presenter-grade microphone options live in other chassis.

🎓 Matching the Kit to the Campus

Choose by the shape of the event. If open days regularly run twenty or more concurrent tours and the calendar also carries graduation weeks, the RC2408's eighty channels are the cheapest insurance against overlap. If the visitors skew young and the route is long, the RC2468's 18 g ear-hook wins the morning and only asks that someone actually run the charging case at lunch. For steady weekly volume on a modest budget, the RC2402 fills the fleet without ceremony. Browse the full tour guide system catalogue for the complete ten-model channel plan, or compare the trio in our other cross-brand match-ups before the next open-day procurement round. The test is unforgiving and repeatable: when twenty families leave the quad at the same minute and none of them heard the wrong guide, the fleet is right.