How to Set Pass-Fail Criteria for a J25 Field Evaluation
A field trial should answer a purchasing question, not produce a collection of favorable anecdotes. Before evaluating ChatField J25, a procurement team should define what must work, where it must work, who will test it and what evidence will count as a pass.
J25 is a phone-paired LoRa mesh communication terminal. The smartphone provides the user interface, connects to J25 through Bluetooth, and the J25 terminals exchange supported communications over LoRa mesh. It should not be evaluated as a traditional handheld walkie-talkie, and it should not be confused with the separate J28 development program.
Start with an operational requirement
Write a one-page test statement before equipment arrives. Include the number of users, the operating area, expected message types, shift length, charging access, phone models and the conditions that cause cellular service to be unreliable. Name the person who can approve a pass, require a retest or reject the trial.
CISA’s National Emergency Communications Plan emphasizes planning and procedures, training and exercises, evaluation, communications coordination and equipment lifecycle management. That public guidance does not endorse ChatField or J25, but it supports a disciplined principle: communications capability should be exercised, evaluated and documented rather than assumed.
Define pass/fail criteria in seven categories
1. Inventory and evidence
Record each terminal, cable, phone, app version and accessory used in the trial. Confirm that the received model and label match the procurement record. For the current J25, the FCC ID is 2BVP9-J25, and the grantee/applicant is Jingxi Box (Shenzhen) Intelligent Technology Co., Ltd. ChatField is the brand. Review the public evidence pathway on the Compliance page; do not apply J25 FCC evidence to J28 or another model.
Example pass: the model identity, label and supplied documentation are consistent across all samples. Example fail: a sample cannot be reconciled with the purchase record or required evidence.
2. Phone pairing and recovery
Test the actual phone models the organization plans to issue. Record initial Bluetooth pairing time, reconnection after moving out of range, recovery after a phone or terminal restart, and the steps a new user needs to follow. Include at least one user who did not help design the test.
Example pass: every approved phone completes the documented setup and recovery procedure within the buyer’s chosen time limit. Example fail: an approved phone repeatedly requires undocumented intervention.
3. Message and voice workflow
Create a fixed script for supported text, location and push-to-talk voice functions. Record sender, recipient, time, route and outcome for every attempt. A procurement test should distinguish delivery, intelligibility and user error instead of combining them into a single impression.
Example pass: the required workflow meets the buyer’s delivery and usability threshold across the planned scenarios. Example fail: a critical message type cannot be completed or reliably recognized.
4. Route and obstruction testing
Choose representative points such as a yard, warehouse edge, hill, concrete structure or work corridor. Do not test only from the easiest open location. Mark endpoints on a map and repeat the same route at least twice so the result can be compared.
Published distance language is an evaluation reference, not a universal promise: up to 10 km in ideal open terrain; about 5 km in tests involving urban high-rise and structural obstruction; and up to two participating relay nodes may be evaluated. Terrain, structures, interference, device position and deployment method can materially change results. The J25 specifications and technology overview explain the buyer-facing boundaries.
5. Relay conditions
If the proposed deployment depends on relay behavior, document the exact node placement and repeat the route with and without the participating relay nodes. Do not count a relay result as a direct-link result.
Example pass: the buyer’s named route works under the documented node layout and the layout can be reproduced. Example fail: the result depends on an unrecorded or impractical placement.
6. Power and shift readiness
Test phones and J25 terminals together for the planned shift pattern. Record starting charge, activity level, charging events and remaining charge. Avoid converting one controlled test into a general battery-life claim.
Example pass: the complete issued kit supports the buyer’s planned shift and charging procedure. Example fail: the workflow requires charging access that the operating plan does not provide.
7. Training and exception handling
Give users a short written procedure, then test missed check-ins, a separated team member, a device restart and a supervisor handoff. Record where users hesitate. Those observations should become training updates or procurement conditions.
Use a simple acceptance table
For each criterion, capture the requirement, test method, threshold, result, evidence file, tester and decision. Mark outcomes as pass, fail or retest; do not use “mostly works” without a defined corrective action. Separate critical criteria—such as the required emergency escalation workflow—from convenience features.
CISA’s published evaluation material notes the value of documenting strengths and improvement areas during communications exercises. FEMA exercise resources similarly organize work around design, conduct, evaluation and improvement planning. Neither source certifies or recommends J25; they provide a useful public framework for disciplined testing.
Turn the trial into a purchasing decision
Approve a purchase only when the evidence matches the operating requirement and the remaining limitations are accepted in writing. If a result fails, decide whether the cause is equipment, phone compatibility, training, route design or an unrealistic requirement before repeating the test.
Start by reviewing J25 product details, then send your test matrix, team size, phone list and route conditions through the ChatField contact page. A B2B evaluation is most useful when both buyer and supplier agree on the pass/fail criteria before the first field test.
Evidence note
Product identity and workflow statements in this article are limited to ChatField’s current J25 materials and FCC ID 2BVP9-J25. Evaluation principles reference the CISA National Emergency Communications Plan, CISA’s Evaluations for Training and Exercises fact sheet, and FEMA HSEEP design and development resources. These agencies do not endorse ChatField, Jingxi Box or J25.