there are several vhf and/or uhf amplifiers out there that are used for repeater use. Some I have seen say fm only.
Question I have is what would have to be added to an amp like that to work on vhf/uhf SSB?
These kinds of amps have RF sensing that tells the amp to "key up" and do its amplification when your radio is transmitting. SSB does not have a carrier, so if you try use an amp with SSB it will rapidly key up and down while you talk... unless it has an SSB mode. The SSB mode will cause the amp to delay unkeying for about a second in the absence of RF from your radio. So if the amp you are using doesn't have an SSB mode, you would have to add a delay circuit. Such a circuit requires a few components. A switch, an electrolytic capacitor and a resistor would probably do the job in most amps. Maybe a relay as well. Someone with electronics experience could probably do it in a few minutes.
An alternative would be to simply add a switch that keys the amp, that you would manually switch on when keying the radio and off when unkeying the radio. Clumsy, but it would work. (I've done that in my past.) Certainly not recommended while driving.
