Hi Tom, The new Harris Flexiva 10 KW FM band (not pulse) stereo transmitter is not having a heat problem with air cooling, in a reasonably small package . It has individual modules that can be hot switched. Will have more info when we install it next few weeks. It's going up on a mountain with no automobile/ truck road, so transporting takes time.
I only meant that it was catching on fast in general. A French design is also making a 2 meter amp. A pair of the devices, with an built in ALC, to keep the output below the non linear portion could could be one approach to a 1.5 KW Amp.. The Harris Salesman, Engineer, Ham, said there was already a W2 using a pair, but had a small water cooled system. 73 Bruce >> This MRFE6VP61K25H solid state device is catching on fast in amateur >> radio >> circles. HF Amps next. >> >> http://www.m2inc.com/pdf_manuals/2M-1K2.pdf > > > Here is the tough time with this, because I'm sure most people take device > manufacturer's data at surface value. All of this stuff, to this point of > time, is mostly vaporware. > > Here are the worries: > > 1.) While manufacturer's make wild claims about device VSWR tolerance, > those > specs are really just creative marketing fantasy. A 2:1 SWR would > instantly > blow the device up if peak voltage breakdown is exceeded, or over a short > period of time if heat limits in the junction are exceeded. If you do not > see SWR fault protection, and there are no current limits, you can bet > devices will fail with some conditions of mismatch. > > Their popular U-tube video is at pulsed service with a power limited > supply. > I can do the same thing with MRF150's, and actually designed a medical > device that ran 1000 watts of peak output power on two MRF150's, without > SWR > protection, on 27.120 MHz. The reason it lived is the power supply would > barely supply 100 watts average power, and it was pulsed duty cycle with > very low Q filters and matching. > > 2.) No SSB IMD spec's. > > 3.) All public data appears to be matched narrow-band class-C pulsed > service. > > 4.) Getting heat out of a small surface transfer area at high power and > high > duty cycles is a major problem. > > There was a good marketing presentation by the device manufacturer, but > nothing indicates it is anything special for HF or linear service, or > going > to "catch on fast". > > 73 Tom > > _______________________________________________ > UR RST IS ... ... ..9 QSB QSB - hw? BK > _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK