09-01-2026, 09:42 PM
Good Evening MrFixr! Thank you for responding.
"Check the resistors R202 for the 14B6 Plate and R300 for the converter and IF screens ". R202 measures 467K, as it should and is attached where it is supposed to be.. R300 measured intermitant; I replaced it with a new 39K. (As an aside, R300 wasn't even in the radio when I began working on it.)
"Is the motorboating there at low volume? Does the frequency change with the volume?" Motorboating is there no matter what the volume control is set at. The frequency does not change with volume.
"There should be a rather large (0.05uF) cap between common and the AVC line this is C304 on the Canada Philco 83 schematic. There is a parallel cap C403, a 0.02 uF cap between the AVC line and common. I don't know why there are 2 caps across the same line unless the schematic is wrong" C304 is there as is C403. Of note, the US equivalent model of the 81 is the 50-520. The 50-520 schematic doesn't have a C403, or an R304.
"There should be also a large value cap between this "Mecca" and the physical chassis. This is C303, a 0.1uF cap." Yup, that's there and goes to the physical chassis.
"If you did this mod (Using a polarized power cord, connecting the neutral directly to the "Common" (Mecca), placing the power switch between the "Hot" side of the power cord and the junction between the 35Z5 filament and plate, make sure that you removed any "jumper" wire from the switch to the "low" end of the volume control." Yes I did the mod and have removed the jumper wire. Thanks for that link, I'm bookmarking it
MrFixr, I'm bushed, and am going to go to bed and sleep on this pick it back up after the gym in the morning. God bless you for all you do here. Joe
"Check the resistors R202 for the 14B6 Plate and R300 for the converter and IF screens ". R202 measures 467K, as it should and is attached where it is supposed to be.. R300 measured intermitant; I replaced it with a new 39K. (As an aside, R300 wasn't even in the radio when I began working on it.)
"Is the motorboating there at low volume? Does the frequency change with the volume?" Motorboating is there no matter what the volume control is set at. The frequency does not change with volume.
"There should be a rather large (0.05uF) cap between common and the AVC line this is C304 on the Canada Philco 83 schematic. There is a parallel cap C403, a 0.02 uF cap between the AVC line and common. I don't know why there are 2 caps across the same line unless the schematic is wrong" C304 is there as is C403. Of note, the US equivalent model of the 81 is the 50-520. The 50-520 schematic doesn't have a C403, or an R304.
"There should be also a large value cap between this "Mecca" and the physical chassis. This is C303, a 0.1uF cap." Yup, that's there and goes to the physical chassis.
"If you did this mod (Using a polarized power cord, connecting the neutral directly to the "Common" (Mecca), placing the power switch between the "Hot" side of the power cord and the junction between the 35Z5 filament and plate, make sure that you removed any "jumper" wire from the switch to the "low" end of the volume control." Yes I did the mod and have removed the jumper wire. Thanks for that link, I'm bookmarking it
MrFixr, I'm bushed, and am going to go to bed and sleep on this pick it back up after the gym in the morning. God bless you for all you do here. Joe
Courage will follow when Faith takes the lead.
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