Tools & Calculators
Calculators
Bench tools for QRP builders. Every result cites its datasheet.
Featured calculators
Inductors & cores
Iron Powder Toroid Turns
Turns for a target inductance, or inductance from turns, on Micrometals iron powder toroids.
- In
- Core, inductance (µH/nH) or turns, wire AWG
- Out
- Turns, actual L, single-layer fit (300° spread)
- Data
- 151 Micrometals and Amidon cores, mixes 0, 1, 2, 3, 6, 7, 10, 12, 15, 17
Inductors & cores
Ferrite Core Turns
Turns or inductance for Fair-Rite ferrite toroids and 2-hole binocular (BN) cores.
- In
- Core, inductance (µH/mH/nH) or turns, wire AWG
- Out
- Turns, actual L, single-layer or hole-fill check
- Data
- 23 FT toroids (mixes 43, 61), 9 BN-61 binoculars
Filters
LC Filter Designer
Low-pass and high-pass LC ladder filters, with a guided Beginner mode and an Expert workbench.
- In
- Response, type, order, cutoff, ripple, source impedance, form
- Out
- L and C values, E12/E24, schematic, S21 and return loss
- Data
- Butterworth, Chebyshev; orders 1–9
Matching
Impedance Matching Calculator
L, Pi and Tee networks that match a source to a real or complex load, with a guided Beginner mode and an Expert workbench.
- In
- Frequency, source and load impedance (R + jX), power, Q
- Out
- Every L, Pi and Tee solution, standard values, SWR bandwidth, part stress
- Data
- L, Pi, Tee and LCC forms; toroid or air-wound coils
Receivers
Cascaded Receiver Calculator
Gain, noise figure, intercept, MDS and dynamic range of a chain of 2 to 20 receiver blocks, with a guided Beginner mode and an Expert workbench.
- In
- Blocks with gain, NF and input or output IP3; bandwidth
- Out
- Chain gain, NF, IIP3, OIP3, MDS, dynamic range, stage-by-stage shares
- Data
- EMRFD Eq 6.10, 6.11, 6.14, 6.15; worked examples Figs 6.64–6.67
All calculators by category
- Inductors & cores
- Iron Powder Toroid TurnsTurns for a target inductance, or inductance from turns, on Micrometals iron powder toroids.
- Ferrite Core TurnsTurns or inductance for Fair-Rite ferrite toroids and 2-hole binocular (BN) cores.
- Filters
- LC Filter DesignerButterworth and Chebyshev low-pass and high-pass LC ladders, order 1 to 9, with schematic, response plot and standard values.
- Matching
- Impedance Matching CalculatorL, Pi and Tee networks that match a source to a real or complex load, with every solution, SWR bandwidth, part stress and standard values.
- Receivers
- Cascaded Receiver CalculatorTotal gain, noise figure (Friis), IIP3, MDS and dynamic range for a chain of filters, amplifiers and mixers.
- LCcoming soon