05-21-2007, 11:44 AM
Hi Dave,
You are correct in the 14 being similar to a 24A. The 17 is similar to a type 27 with higher voltage on the heater. I used to have a General Electric type 14 made in the early 1940's for replacement in the model 46. It had the later ST shaped envelope. I gave it Robert Millard who used it in his book he published a few years ago on vintage tubes. He has a good photo of it there.
I am fascinated with DC only sets and at this time have an Atwater Kent model 41. It has metal plaques in the inside and on the back warning it is for DC only. I made up a power supply for it but right now I still need to use an isolation transformer (a must with these sets) with an input tap to get the 115 volts DC out of it and a rectifier-filter setup. I am not sure what the current draw of your set is. The Atwater Kent uses a bunch of 112A and 71A tubes in series so the current on my set is probably about 300ma. The Philco 46 may be a little higher.
Fred R
You are correct in the 14 being similar to a 24A. The 17 is similar to a type 27 with higher voltage on the heater. I used to have a General Electric type 14 made in the early 1940's for replacement in the model 46. It had the later ST shaped envelope. I gave it Robert Millard who used it in his book he published a few years ago on vintage tubes. He has a good photo of it there.
I am fascinated with DC only sets and at this time have an Atwater Kent model 41. It has metal plaques in the inside and on the back warning it is for DC only. I made up a power supply for it but right now I still need to use an isolation transformer (a must with these sets) with an input tap to get the 115 volts DC out of it and a rectifier-filter setup. I am not sure what the current draw of your set is. The Atwater Kent uses a bunch of 112A and 71A tubes in series so the current on my set is probably about 300ma. The Philco 46 may be a little higher.
Fred R
