This 25GHz Oscillator May Be the Fastest Thing to Ever Land on a Breadboard
Responding to a challenge on the EEVblog forum, Joe Smith has built a breadboarded 25GHz oscillator — a world record.
Joe Smith has published a video of what may well be the fastest breadboard-based oscillator component in history, achieving 25GHz in response to a challenge posted on the EEVblog forum.
"The aim is to achieve the highest frequency on the EEVblog forum. The current record holder may call himself the incumbent master oscillator for the time the record is held," the rules of the challenge, as posted on the EEVblog forum earlier this year, state. "1. No ICs (duh!) 2. No crystals / MEMS etc. 3. No soldering except to add wires to SMT parts. All electrical connections between individual parts must be made by the breadboard contacts."
"4. The output signal shall be sine(-ish) and able to drive a 10k load at at least 5Volts peak to peak. You may deviate from this rule within reason as we have arrived at microwaves. 5. Self-made discrete parts are allowed and encouraged."
Smith's response to the challenge came when his friend claimed to have reached an impressive 20GHz. "For my final entry," Smith notes, "I managed to get this breadboard oscillator to work slightly over 25GHz."
While the original design was somewhat unstable, Smith was able to resolve the problem with a custom shield fitted over the oscillator components on the breadboard — something which the rules don't forbid.
"A friend of mine who used to work for Motorola as an RF engineer watched my first video where I show the 6GHz oscillator, so he decided he wanted to get in on the competition with the 20GHz oscillator," Smith explains. "So over the last few weeks I've been asking him to see this oscillator. The other day this package shows up — a fragile 20GHz VCO. It got me thinking about turning my friends imaginary oscillator into reality — basically trying to build a 20GHz oscillator on a piece of breadboard."
The project was a success, though not without its challenges — including having to adjust measurement equipment to accurately read at such high frequencies. The full video is available on Smith's YouTube channel, giving him the crown of master oscillator — at least, until the next challenger appears.