Gerry Sweeney has been selling something like this for ages now: https://www.tindie.com/products/gerrysweeney/five-decade-programmable-capacitor-100pf-to-9999u

Gerry Sweeney has been selling something like this for ages now: https://www.tindie.com/products/gerrysweeney/five-decade-programmable-capacitor-100pf-to-9999uf-100v/ https://www.tindie.com/products/gerrysweeney/five-decade-pro... I've got his programmable resistor, and its quite handy: https://www.tindie.com/products/gerrysweeney/seven-decade-programmable-resistor-1r-9999999r-1-500mw-gerrysweeneycom/ https://www.tindie.com/products/gerrysweeney/seven-decade-pr...