I find it amazing how some specific issue with a project will spawn a whole new design and so it is with the Sudden Driver Stage. In a 1985 edition of Ham Radio Magazine, K1BQT, Rick Littlefield, presented a design for a 75M SSB transceiver that used mostly IC's such as the MC1496 and the MC1350. His Driver Stage final device used a RF MOSFET (IRFZ10) that is no longer available and thus in 2018 when I was entertaining a rebuild of that project I was a faced with a gaping hole in my design. Initially I looked at some replacements since this device as used in the K1BQT rig only needs to produce 300 MW to drive the final linear amp to 30 watts (a RF MOSFET from Motorola the MRF137). My initial replacement candidates included the 2N7000 and the 2N7002. But a key factor was to be able to simulate my replacement circuit in LT Spice so that the deisgn paramaters could be optimized for the bands being used. Since I have a stock of 2N2219's and that particular device has a Spice model, I was off and running and a replacement design evolved using the 2N2219. I was successful in the use of the 2N2219. Since building the Sudden Transceiver, I have now revised the Driver Stage design so that the output while still broadbanded now has an ouput greater than the original configuration or approximately 25 dBm. That extra bit of gain will help should the 20M variant be the band of choice. There is essentially one component added to the original and that is an emitter bypass capacitor of 100 nF. I also moved the feedback tap to the collector versus the source. Originally my starting simulation had the feedback tap connected to the midpoint tap of a bifilar wound transformer. I removed one of the windings to effect a broader response; but somehow left the connection at the midpoint which was now the source end. While that works as an amplifier, greater gain can be acheived using the tap at the Collector and adding the Bypass Cap to the Emitter. Use the 100 nF value as something less will give a peaked response at a higher frequency which is not useful for this project. The note on the schematic about a 10 dB gain increase reflects an increase over the original configuration. With an output of 11 Volts Peak to Peak this amp is doing 300 MW or about 25 dBm (24.8 dBm). So it has a healthly bit of gain. [11^2 = 121. 121 * 2.5 = 302.5 MW. 10*log(302.5) = 24.8 dBm. All this is saying if you take the PTP reading in volts across 50 Ohms and square it and then take that value times 2.5 that equals the Milli-watt output. The trickery is in the conversion of the PTP to RMS and then multiplying by 1000 to get milliwatts --all with a 50 ohm load. Go ahead and do the detailed math and you will see my shortcut gets you there. The final piece is to reference the power output to 1 milliwatt --- that is the "m" in dBm. Thus 10 times the log of your power output in milliwatts is dBm. You can check it -- 1 watt or 1000 milli-watts is 30 dBm and of course 2 watts (2000 MW) is 33 dBm --double the power and you get a 3 dB gain increase. Amazing!] There are some cautions here as with any amplifier circuit and that principally has to do with layout. Haphazard layouts promote feedback paths and with high gains your beloved amplifier now is an oscillator. Wes Hayward in his seminal publication Solid State Design for the Radio Amateur (SSDRA) discusses steps to address the feedback issues as well as the application of what he calls band-aid fixes. Sell your EMRFD and get a SSDRA (just my opinion).