Source: https://guthlabs.ai/docs/instruments/filter-designer-rc-low-pass-high-pass/implementation/

instrument implementation / implementation-contract

# Filter Designer — RC Low-Pass/High-Pass implementation

A source-bound implementation contract for Filter Designer — RC Low-Pass/High-Pass; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-028

**Effect**: Computation or source lookup only

## Input and validation requirements

The zero-resistance input produces an undefined cutoff and must be rejected; additionally, unspecified component units can produce a 1,000,000-fold cutoff-frequency discrepancy.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "topology": "low-pass",
    "R_ohm": 10000,
    "C_F": 1e-8
  },
  "expected_outputs": {
    "fc_Hz": 1591.54943,
    "minus_3dB_frequency_Hz": 1591.54943
  },
  "working": "C=10 nF=10×10^-9 F=1×10^-8 F. RC=10000×1×10^-8=1×10^-4 s. 2πRC=2π×1×10^-4=0.00062831853. fc=1/0.00062831853=1591.54943 Hz. For an ideal first-order low-pass, the −3 dB frequency equals fc."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/filter-designer-rc-low-pass-high-pass/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/filter-designer-rc-low-pass-high-pass/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/filter-designer-rc-low-pass-high-pass/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`