Mfj 259. MFJ 259 D SWR Analyzer / 1,8 170 MHz FGH Electronics This combination of circuits allows measurement of the SWR (referenced to 50 ohms) of any load connected to the ANTENNA connector But the MFJ-259 is still very easy to use, and accurate enough for my own projects.
Mfj 259 Exploring the Schematic from wireblueprint.com
The analyzers make a wide variety of useful antenna or impedance measurements, including coaxial cable loss and. They combine four basic circuits; a 1.8-170 MHz variable frequency oscillator, a frequency counter, a 50 ohm RF bridge, and an 8-bit micro-controller
Mfj 259 Exploring the Schematic
The analyzers make a wide variety of useful antenna or impedance measurements, including coaxial cable loss and. This combination of circuits allows measurement of the SWR (referenced to 50 ohms) of any load connected to the ANTENNA connector MFJ 259B HF/VHF SWR analyzers are compact, battery-powered RF impedance analyzers
MFJ MFJ259D MFJ 259D 280 kHz 230 MHz plus 2200 Meter Antenna SWR. •MFJ 259: 50 & 100 ohms •MFJ 259B: 12.5, 50, 75, & 200 ohms •Easy to make your own load with stock resistors and PL 259s •Use the smallest METAL FILM (1%) resistors you can find •Radio Shack CARBON FILM resistors worked for me •Philips screwdriver (#1 or #2) They combine four basic circuits; a .53-230 MHz variable frequency oscillator, a frequency counter, a 50 ohm RF-bridge, and an 8-bit micro-controller
Mfj 259 circuit diagram an inside look. I replaced it with a new 269, which at that time could be purchased new for under $300 I still have that 269, but I found another working 259 at a hamfest and snapped it up