02-17-2020, 07:56 PM
Hi,
I have both a code 121 and a code 125. Philco may have done some changes along the way as the way as the code 121 has an RF sub-chassis with the coil line up of a code 125 and the code 125 has the line up of the code 121. Some of the coil resistances listed in either service bulletin 250 or 251A do not match the values listed on the schematic. Some of the coils are wound with lintz wire and some used that wire to go from the coil terminals to the band switch. Removal of a bad coil is best done by removing the RF sub-chassis then removing each section one at a time starting with the Antenna section (rear of chassis), then the RF section (mid chassis) and finally Osc. section (front of chassis). Mark all wires and de-solder carefully. The coil terminals and the eleven lug terminal strip lugs on the side are easily broken.
Make a step list as you go so reinstall is just the reverse. Hint - Remove the power/tone switch and lay to the side. Then remove the hex screws that hold the front chassis panel and remove it with the volume control shaft still attached to it. (keep track pf the brass clip on the end of the shaft that inserts into the volume control.)
Then it is a matter of removing the center RF chassis screw and rubber bushing, and tilting the RF sub-chassis up and forward with the band switch still in place. Note the band switch shaft has a small tit on the rear end with corresponding notches on each wafer. With the RF sub-chassis on the bench, removal of the shaft and sections is straight forward.
If you go to all of this trouble, replace all the paper caps with new 630 volt units. mine were all leaky. Some of the resistors were OK and some were not. Some of the resistors are of odd values not made any more. The color code follows the standard body-end-dot code. Using the value on the resistor or schematic, if any are over 20% off, you can use any replacement that a standard value part falls in the 20% range. I used 5% resistors as replacements and found they work fine.
FYI, I have a Morris replica that I have rewound some of the coils with. The ones with Lintz wire, I didn't have much luck with.
Good luck with your restoration. Please feel free to ask any questions. If possible zap a photo of the RF sub-chassis section and I will see if I can rewind to coil for you or provide a replacement from my parts chassis.
Gerald D,
grumpysailor2016@gmail.com
I have both a code 121 and a code 125. Philco may have done some changes along the way as the way as the code 121 has an RF sub-chassis with the coil line up of a code 125 and the code 125 has the line up of the code 121. Some of the coil resistances listed in either service bulletin 250 or 251A do not match the values listed on the schematic. Some of the coils are wound with lintz wire and some used that wire to go from the coil terminals to the band switch. Removal of a bad coil is best done by removing the RF sub-chassis then removing each section one at a time starting with the Antenna section (rear of chassis), then the RF section (mid chassis) and finally Osc. section (front of chassis). Mark all wires and de-solder carefully. The coil terminals and the eleven lug terminal strip lugs on the side are easily broken.
Make a step list as you go so reinstall is just the reverse. Hint - Remove the power/tone switch and lay to the side. Then remove the hex screws that hold the front chassis panel and remove it with the volume control shaft still attached to it. (keep track pf the brass clip on the end of the shaft that inserts into the volume control.)
Then it is a matter of removing the center RF chassis screw and rubber bushing, and tilting the RF sub-chassis up and forward with the band switch still in place. Note the band switch shaft has a small tit on the rear end with corresponding notches on each wafer. With the RF sub-chassis on the bench, removal of the shaft and sections is straight forward.
If you go to all of this trouble, replace all the paper caps with new 630 volt units. mine were all leaky. Some of the resistors were OK and some were not. Some of the resistors are of odd values not made any more. The color code follows the standard body-end-dot code. Using the value on the resistor or schematic, if any are over 20% off, you can use any replacement that a standard value part falls in the 20% range. I used 5% resistors as replacements and found they work fine.
FYI, I have a Morris replica that I have rewound some of the coils with. The ones with Lintz wire, I didn't have much luck with.
Good luck with your restoration. Please feel free to ask any questions. If possible zap a photo of the RF sub-chassis section and I will see if I can rewind to coil for you or provide a replacement from my parts chassis.
Gerald D,
grumpysailor2016@gmail.com
