09-02-2023, 12:41 PM
I have a Philco-model 41-255 which has a three section candohm in it; however, no wattage for each is not shown. Any clues would help as far as replacement, if needed. Thanks
09-02-2023, 12:41 PM
09-02-2023, 02:13 PM
Welcome to the Phorum chradios! Are you referring to part 61? The schematic and other information is available in the Service Section of the Philco Radio Library, service info accessed at the bottom of the page. https://philcoradio.com/library/index.ph...year-book/
Take care and BE Healthy! Gary
Take care and BE Healthy! Gary
09-02-2023, 06:09 PM
YOu could do rough assessment.
You need to know the current. The assumption is that the current through the choke is the same that goes from the Ground back to the centertap of the rectifier.
The dropout across the choke is 85V at 1100 Ohm, making it 77mA. Let's make it 80 mA.
The total resistance of the "Candohm" is 192 Ohms. This makes it 1.14W total.
The dissipation on the sections is proportional to their resistances, so it will be 0.87W, 0.18W and 0.09W respectively.
Now triple the ratings: 3W, 0.5W and 0.25W for 146, 31 and 15 Ohms respectively. These are the ratings for the sections. Of course you could use large ratings. I usually go for triple where the circulation is good and no combustible material is nearby.
You need to know the current. The assumption is that the current through the choke is the same that goes from the Ground back to the centertap of the rectifier.
The dropout across the choke is 85V at 1100 Ohm, making it 77mA. Let's make it 80 mA.
The total resistance of the "Candohm" is 192 Ohms. This makes it 1.14W total.
The dissipation on the sections is proportional to their resistances, so it will be 0.87W, 0.18W and 0.09W respectively.
Now triple the ratings: 3W, 0.5W and 0.25W for 146, 31 and 15 Ohms respectively. These are the ratings for the sections. Of course you could use large ratings. I usually go for triple where the circulation is good and no combustible material is nearby.
09-09-2023, 03:45 PM
Can I use Metal Film resistors for the 2 lower wattage on the candohm?
09-09-2023, 08:45 PM
hello Chradios,
Yes you sure can use metal film resistors !
just make sure to give your self enough over rated wattage that way it will run cooler and last longer .
Sincerely Richard
Yes you sure can use metal film resistors !
just make sure to give your self enough over rated wattage that way it will run cooler and last longer .
Sincerely Richard
09-09-2023, 08:49 PM
Rich meant resistors.
As he said, you could use any whatsoever. As long as the wattage is appropriate.
As he said, you could use any whatsoever. As long as the wattage is appropriate.
09-11-2023, 07:31 AM
Hello Morzh ,
Yes I editted my post to resistors .
Sincerely Richard
Yes I editted my post to resistors .
Sincerely Richard