Hi everyone!
We have recently decided to build an amplifier based off Peter Blomley's original design found in Wireless World:
http://www.keith-snook.info/wireles... to class-B Amplifier Design by P Blomley.pdf
We have faithfully reproduced his circuit schematic while updating components to modern, easy to find variants. Can anyone see any obvious, glaring problems with the attached Gerbers when compared to his schematic found on pg.6 of the linked article?
Many thanks in advance and Merry Christmas!
We have recently decided to build an amplifier based off Peter Blomley's original design found in Wireless World:
http://www.keith-snook.info/wireles... to class-B Amplifier Design by P Blomley.pdf
We have faithfully reproduced his circuit schematic while updating components to modern, easy to find variants. Can anyone see any obvious, glaring problems with the attached Gerbers when compared to his schematic found on pg.6 of the linked article?
Many thanks in advance and Merry Christmas!
JLH was a fan of Blomley and commented on his circuit in EW/WW , I take it you will be using high Ft and high speed modern devices and notice the low amount of feedback in his design .
JLH took heed of that and TID and positioned his feedback capacitor in a position of least harm to TID and used a 5pf capacitor in his own design --- I built the same , a lot of care is needed to keep the feedback within that value .
it should be a lot easier now in 2020 to buy components of very high quality there were pricey in my day.
For those thinking of building a Blomley amplifier --don't cut corners or buy dodgy components.
JLH took heed of that and TID and positioned his feedback capacitor in a position of least harm to TID and used a 5pf capacitor in his own design --- I built the same , a lot of care is needed to keep the feedback within that value .
it should be a lot easier now in 2020 to buy components of very high quality there were pricey in my day.
For those thinking of building a Blomley amplifier --don't cut corners or buy dodgy components.
Does your PCB design not automatically link to the schematic drawing? Normally that will ensure that the schematic and PCB match with perfect connectivity.
Jan