Anyone tried a SPB-2026Z amp?
Posted: Wed Feb 15, 2012 10:11 pm
I bought a couple of the RFMD SPB-2026Z devices and matching PCBs from here: http://www.ebay.co.uk/itm/RFMD-0-7-2-2G ... 0391561412 recently in the hope that they would make a good driver for the 23cm DigiLite. There's more info for 23cm use here: http://s3.amazonaws.com/zanran_storage/ ... 722956.pdf
They are supposed to have good linearity as they're designed for cellular applications with a P1dB of 25dBm and a gain of around 13dB. However, while the one I built up draws the right quiescent current and if driven hard enough the current can reach almost 1A, I'm only getting around 3dB power gain.
I've tried a different choke in the output pin supply and made sure that the ouput circuit is not open or s/c to ground but I can't understand why I can't get all that supply current converted to RF.
Ideas anyone?
They are supposed to have good linearity as they're designed for cellular applications with a P1dB of 25dBm and a gain of around 13dB. However, while the one I built up draws the right quiescent current and if driven hard enough the current can reach almost 1A, I'm only getting around 3dB power gain.
I've tried a different choke in the output pin supply and made sure that the ouput circuit is not open or s/c to ground but I can't understand why I can't get all that supply current converted to RF.
Ideas anyone?