01-23-2018, 07:15 AM
Aaran;
I did find two versions on the Radio Daze site; SKT-8L-C1and SKT-8L-C2. One has lugs with holes to slip leads through and the other has lugs with no holes and are made for solder to a circuit board. The original Loctal sockets in this model have lugs with no holes and the wires are wrapped around the lugs. So the closest version from Radio Daze would be the ones made for circuit board use if its dimensions allow it to fit. The dimensions were not given, so I wrote them asking for that detail. I will report on the dimensions when I hear from them. The socket opening in the chassis is 1.035 inches and the rivet holes are 1.325 inches apart measured with my dial caliper. The bottom of the Octal socket I installed fit easily in the socket circle opening with some room to spare. I used 4-40 hardware to mount the new Octal socket.
I ordered a 6SG7 from AES and contacted a friend about getting some 6K6GT/G tubes for the push-pull output stage. I did measure the grid bias yesterday and it was at -19.9VDC at both output tubes. That is quite a lot higher than the -11V shown on the schematics for the various versions of this model. The resistor in the power supply that establishes this bias appears to be an original Philco part but measures 260 ohms instead of 165 ohms shown on at least some versions of the schematic that I see. That would explain the grid bias being higher than indicated.
I have been working from the schematics that jcassity posted plus a Beitman's schematic supposedly for the Code 125 version. I have been redrawing the Beitman's schematic to make it clear and easy to read. That has been helpful and everything I have found so far agrees with the chassis version that I have except for the 260 ohm resistor in the negative bias circuit, the absence of a field coil and the presence of a PM speaker. I also have downloaded the Rider's 47-1227 service data and it also agrees in many details with the 46-1226 Code 125 version. The strange thing about the Code 125 version I have is that it appears to have an original Philco permanent magnet speaker installed instead of a field core version. Even the 47-1227 version service data indicates a field core speaker was used. The schematic shows the speaker also is supposed to have a hum bucking coil in it. The connector for the speaker in this set has holes to accept the 4-prong male plug mounted on the speaker frame. There are only two leads going to the speaker in this set. I have no way of knowing if it ever had a different speaker or extra leads to it.
Joe
I did find two versions on the Radio Daze site; SKT-8L-C1and SKT-8L-C2. One has lugs with holes to slip leads through and the other has lugs with no holes and are made for solder to a circuit board. The original Loctal sockets in this model have lugs with no holes and the wires are wrapped around the lugs. So the closest version from Radio Daze would be the ones made for circuit board use if its dimensions allow it to fit. The dimensions were not given, so I wrote them asking for that detail. I will report on the dimensions when I hear from them. The socket opening in the chassis is 1.035 inches and the rivet holes are 1.325 inches apart measured with my dial caliper. The bottom of the Octal socket I installed fit easily in the socket circle opening with some room to spare. I used 4-40 hardware to mount the new Octal socket.
I ordered a 6SG7 from AES and contacted a friend about getting some 6K6GT/G tubes for the push-pull output stage. I did measure the grid bias yesterday and it was at -19.9VDC at both output tubes. That is quite a lot higher than the -11V shown on the schematics for the various versions of this model. The resistor in the power supply that establishes this bias appears to be an original Philco part but measures 260 ohms instead of 165 ohms shown on at least some versions of the schematic that I see. That would explain the grid bias being higher than indicated.
I have been working from the schematics that jcassity posted plus a Beitman's schematic supposedly for the Code 125 version. I have been redrawing the Beitman's schematic to make it clear and easy to read. That has been helpful and everything I have found so far agrees with the chassis version that I have except for the 260 ohm resistor in the negative bias circuit, the absence of a field coil and the presence of a PM speaker. I also have downloaded the Rider's 47-1227 service data and it also agrees in many details with the 46-1226 Code 125 version. The strange thing about the Code 125 version I have is that it appears to have an original Philco permanent magnet speaker installed instead of a field core version. Even the 47-1227 version service data indicates a field core speaker was used. The schematic shows the speaker also is supposed to have a hum bucking coil in it. The connector for the speaker in this set has holes to accept the 4-prong male plug mounted on the speaker frame. There are only two leads going to the speaker in this set. I have no way of knowing if it ever had a different speaker or extra leads to it.
Joe
