2M 100w RF Power Amp?

[Dys0n]

Hey,

I have a station with a 120w transmitter all set up (thanks to RF Burns) but like always we want back up transmiters we have a 5w PLL Transmiter and i was looking at a 2m 100W RF Power Amp on ebay it says its for AM/SSB and on the listing the guy said he used SSB with fm and it worked fine would this be able to bost my 5w to 100w?

[Kage]

There is no such thing as using SSB on FM. FM and SSB are two different modulation modes. If anything SSB is closer related to AM work.
An amplifier that can do any of those modes on VHF could technically be converted for FM only usage.

144MHz 2meter ham band is far enough away from the FM broadcast band that it would take some modifications to get the amp down near the broadcast band. Probably would have to replace most of the input and output coils, possibly even capacitors.
Also the transistors in the amp may operate slightly different with the lower frequency having more gain or some other odd characteristic that the amp was not originally designed to handle.
The only way around this is if the amp was originally designed for wideband operation, which most ham amps for VHF/UHF aren't.

I would highly suggest not doing this. You could try it if you have the proper equipment and knowledge to convert it down to the broadcast band, but for the work involved you may as well just get an amplifier originally designed for the FM broadcast (3 meter) band.

[Dys0n]

Ahh cheers i'm a software engineer and i do a lot of electronics but i cant seem to find a decent schematic for a an amp that don't require tons of power to run i only need about 100 - 150w's

[RFBurns]

Kage is spot on about the 2m amp running in 3m band, it will have to basically shove that 3 meter stuff through itself, drawing more current while trying to do it, and possibly going outside of the design characteristics which make the amplifying elements, be it FETs or transistors, run hotter, work harder, and possibly just blowing on you.

Thing about power levels at the 50 watt range and above is going to require a well regulated, and well filtered power supply that can deliver the necessary current and voltage, and at 100 to 150, requires that much more of a power supply. But one thing is for sure, that 2 meter ham band amp isn't gonna do the job and do it right.

Indeed, just get another 3 meter FM broadcast amp designed for that band, preferably a wide band amp (no tuning stages or tuning required), a good low pass filter (preferably 7 pole or more), and there ya go.

Peace!