Make every loss term visible.
Build a simple RF path budget from entered attenuation, or estimate the dielectric contribution of an ideal microstrip. Keep partial material estimates separate from a complete measured insertion loss.
RF path-loss budget and dielectric estimate
Choose a measured/modelled distributed-loss budget or an ideal dielectric-only microstrip estimate. Extra fixed loss is added in dB under a matched-cascade assumption.
Budget mode: loss = entered dB/m × lengthm + fixed dB. Dielectric mode: αd = πf/c × εr/√εeff × (εeff−1)/(εr−1) × Df in Np/m; multiply by 8.685889638 for dB/m. It excludes conductor, roughness, radiation, connectors and mismatch unless separately supplied. Not a full insertion-loss prediction.
Choose the mode that matches your evidence
The entered-budget mode multiplies a supplied attenuation coefficient by line length and adds a fixed allowance. The coefficient can come from a representative measurement or a suitable model. It is not inferred from a laminate name. Use the value at the frequency and construction relevant to the design.
The dielectric mode estimates one contribution using substrate permittivity, effective permittivity, loss tangent, frequency and geometry ratio. It omits conductor and roughness losses, radiation, transitions and mismatch. The output is explicitly labeled a partial budget. A small dielectric term does not mean that a finished board or assembly will have equally small insertion loss.
Define ports and avoid double counting
A loss measurement depends on the network boundaries. A fixture or connector can be included in the result unless the calibration and de-embedding procedure remove it appropriately. Before adding a fixed connector allowance, check whether the supplied distributed coefficient already contains that connector contribution.
Simple addition in dB assumes a suitable matched cascade. Multiple reflections between mismatched sections can produce frequency-dependent behavior that scalar addition does not capture. For an actual channel with important discontinuities, use S-parameter network analysis or a representative measurement. Keep the frequency sweep and reference planes documented.
Why Df alone does not predict a finished board
Loss tangent describes dielectric behavior under a measurement condition. The complete path also depends on copper profile, final finish, trace geometry, substrate thickness and surrounding fields. A narrow line and a wide line on the same laminate do not necessarily have the same conductor contribution.
Review RF surface finishes and the sourced material data when building a model. A value quoted at 10 GHz should not silently become a measured value at 77 GHz. In dielectric mode, you are responsible for supplying a loss tangent appropriate to the frequency; the tool does not extrapolate a material dispersion model.
Interpret the power ratio carefully
For the stated matched-path assumption, a positive loss in dB converts to a delivered-power fraction through 10 raised to minus loss divided by ten. This is a useful consistency check. It is not a temperature calculation, and missing delivered power is not automatically all heat in the dielectric.
Use a loss budget to identify which assumptions need evidence. If a design has a tight margin, compare simulation with a coupon or assembled network that represents the critical structures. Record material, copper, finish, length, calibration and temperature with the result. The quality and test review helps define what should be included in the order acceptance package.
Keep the engineering assumptions connected
Build the acceptance plan around the application
Decide what the bare board must demonstrate and what belongs to the assembled product. Continuity testing, an impedance coupon, a calibrated RF network measurement and an installed-system test are different forms of evidence. None should silently stand in for another. Identify the required report, coverage, limits and review responsibility before the quotation is accepted.
Record the test configuration alongside the result: board revision, material construction, fixture, calibration, firmware or device settings, temperature and the relevant operating point. When comparing prototypes, keep these conditions consistent or explain the difference. A changed connector, cable or reference plane can make an apparent board improvement difficult to interpret.
For production, agree how first-article findings become controlled manufacturing requirements. Identify which dimensions and material choices are critical, what may be adjusted by engineering, and which changes require renewed validation. A repeat order should reference the approved revision and test plan rather than rely on a previous email description.
Visit quality and test evidence for supplier qualification and reporting questions. Where a customer program requires certificates or sector-specific approval, request the actual documents and applicable scope. An application example is not a product certification or a substitute for the customer’s acceptance process.
Prepare a quotation that engineering can review
A useful RF PCB quotation starts with a controlled design package. Send Gerber or an agreed manufacturing format, NC drill data, a dimensioned outline, the board revision and a stackup drawing. Add quantity, delivery destination and the requested schedule. If some details are still open, mark them explicitly instead of letting a drawing, an email and a file name imply different requirements.
Separate mandatory requirements from preferences. A specified laminate, a customer-approved alternative and a request for a recommendation are three different purchasing instructions. State whether the supplier may propose changes to dielectric thickness, line geometry, panelization or finish, and who approves those changes. Changes that affect RF behavior should return to the design owner before release.
What affects the price?
Board area and panel utilization, quantity, material availability, stackup complexity, drilling and plating, special mechanical features, inspection and test all influence cost. Tight tolerances can also change the achievable yield and process route. An online estimate cannot account for every interaction in an unusual construction.
Use the panel and material cost tool to explore the assumptions it exposes, then request a reviewed quotation. Confirm tooling or setup charges, engineering changes, shipping, taxes and the included report package in the commercial offer.
What affects delivery?
Material stock, engineering clarification, special tooling, lamination cycles and the agreed inspection plan can affect the schedule. Assembly adds component procurement, stencil preparation, programming and fixture readiness. The requested date is a planning input until the supplier confirms the complete order scope.
The website’s response-time target describes enquiry handling. It is not a guarantee that a complex RF build can be priced, fabricated or delivered within the same period. Ask the team to identify the critical dependencies for your project.
From review to repeatable production
Agree the build
Engineering reviews material, geometry, mechanical features and test requirements. Open questions and proposed changes are documented. The approved drawing and stackup become the manufacturing baseline.
Verify the first build
Define which records are needed for the prototype: electrical test, impedance, dimensional inspection, cross-sections or an agreed RF measurement. Evaluate the evidence against the relevant acceptance criteria.
Control later changes
Keep revision, material substitutions, process changes and test updates traceable. A successful prototype is the starting point for production control, not permission to change the construction silently.
For a performance issue, retain the board revision, lot reference, measurement setup and operating conditions. Comparing repeatable measurements is more useful than comparing screenshots taken with different fixtures or calibration. Define the investigation and disposition with the supplier using the actual order requirements.
Prepare an engineering review from this resource
Select what is ready. This checklist runs locally and does not upload files or place an order.
From an online result to a manufactured board
RFPCB and PCBSync share a manufacturing operation. The photographs below show real process and laboratory areas from that facility archive. An online calculation is an engineering aid; a quotation and acceptance plan still need the actual design package.
RF PCB Insertion Loss Calculator & Budget: common questions
Does dielectric mode include copper roughness?
No. It estimates dielectric loss only, plus any fixed allowance you explicitly enter.
Can I add measured losses in dB?
Only under an appropriate cascade assumption and consistent reference planes. Mismatch interactions can require S-parameter analysis.
Is Df at 10 GHz valid for every operating frequency?
Not automatically. Use a supported material model or measurement at the frequency and conditions relevant to the design.
Related RF design resources
PCB Impedance Calculator — Microstrip & Width Solver · RF PCB Insertion Loss Calculator & Budget · RF PCB Dk / Df Comparison Table · RF PCB Material Cross-Reference & Candidate Tool · RF PCB Stackup Library — 2, 4, 6 & 8 Layers · RF PCB Design Guide & Review Checklist
Continue with controlled impedance manufacturing, hybrid stackup review or a project enquiry when your assumptions are ready for engineering review.
Model and data sources
Sources reviewed September 2026. Original supplier documents control their stated values and conditions. Educational stackups and calculations are not manufacturing approvals. The page explains the model scope rather than claiming full-wave accuracy or material equivalence.
Send the assumptions with the design.
Include the model, material source, stackup, geometry and acceptance needs. The engineering team can review open questions and confirm a quotation scope.
Related engineering decisions
Ready for a quotation?
Send your requirements for a material, stackup and manufacturing review. Price and schedule are confirmed for your project.