Posted in vna

VNA parts list

The parts list here is the digikey parts list . It contains everything needed, except: 1. Transformers – these were…

Posted in audio

Electret mic amp

High sensitivity (36dB gain), tested for low harmonic distortion and flat frequency response (1dB down at 40Hz, flat past 30kHz)….

Posted in dielectric constant relative permittivity transmission lines

More on transmission lines

PTFE has a more constant (!) dielectric constant over a reasonable frequency range (not that the 4 ohms delta of…

Posted in dielectric constant relative permittivity transmission lines

Transmission line calculation tool

Since the steps were too much, this excel file was created. In the spreadsheet, the green values can be entered,…

Posted in dielectric constant relative permittivity transmission lines

Twisted pair transmission line

For constructing transmission lines, coax is useful because it is available in 50 and 75 ohms. For transmission line transformers,…

Posted in general electronics

Wire gauges

Wire gauge Excel spreadsheet with AWG and SWG (in inches and mm). American Wire Gauge                Standard Wire…

Posted in eagle

DXF / HPGL to eagle script conversion

There are some Autocad DXF <-> Eagle converters available but they seem to be demo versions, and I didn’t get…

Posted in vna

VNA board chopped up

 (with a spinning wheel cutting tool, I forget what it is called).

Posted in PoE supply

48v 150W power supply (12V step-up)

This allows 48v equipment to be powered from a 12v battery… ideal for power-over-ethernet devices which need 48v. A commercial…

Posted in audio ipod

Audio boards (for sale)

This board is a generic audio controller with decent sound. It was designed for an ipod but can be used…