> There's no way any of them will get close to 6 GHz without LN2. No need for LN2, you could probably achieve this easily using a closed loop CO2 system. But I

> There's no way any of them will get close to 6 GHz without LN2. No need for LN2, you could probably achieve this easily using a closed loop CO2 system. But I'm not aware of any such systems readily available. Kinda seems like an unfilled niche to me.