Batboard

I've read that Kenwood TK-790's will do 5 watts on low-power transmit.

Does anyone know if there is a duty-cycle limit?

I'm used to Motorola radios like Maxtracs and GM300's that tend to run hot or even hotter than high power while at low power.

Anyone know if the TK-790 will do 5 watt transmit for a long period of time, for example, a repeater transmitter?

I use an MCS2000 VHF low power model I for an Echolink node. Runs on low power (10w IIRC) just fine, but I do use a forced air fan on it.

Been running it for a year with lots of extended keydowns and never a problem.

I think the 790 would be only IF you did the same thing. Fan is a must for any mobile radio at any power level, except maybe those 2 watt special industrial low power GM300/Maxtracs that were made.