[amsat-bb] RF power required for linear satellites?

Hello AMSATers,

I’m wondering if 5 watts is generally sufficient RF output to work the common linear satellites using a handheld satellite antenna (Arrow or Elk)?

For example, would an FT-817ND (or the new FT-818) suffice for the uplink radio, or would you need an amplifier with those 5 (6) watt radios, or just a more powerful radio such as the FT-857D?

Thanks & 73, Ken VA7KBM