11-14-2017, 09:51 PM
Hi Mark,
>at some point, electrolytics were replaced
So point is a bit vague post a pic to give us a better idea of the time frame. Values aren't very critical and manufacturers try to use the smallest value possible as it's cheaper. I would probably use a pair of 10mf @ 450v just for convenience. With that being said on older ac sets from the late 20's and early 30's that use small value caps like 1 and 2mf caps are more critical and should stick to the original values.
>When I read from the Rectifier plates I should get 1050 ohms.
Would lose any sleep over it. Check to see if the AC voltage from each plate to the chassis, should be fairly even within a few volts. Generally I look for signs of over heating like wax under the transformer on the cabinet or the transformer get hot w/o the rectifier tube plugged in after 5 or so minuets.
> Checking from the green center tap to pin 2 is 380 and pin 3 is 360.
To have the same number of turns from center to each end the inside winding is going to be shorter than the outside as it is wrapped around the inside. Longer winding = higher resistance.
> but looking for your expert advise.
[Image: http://philcoradio.com/phorum/images/smi...on_lol.gif] Just a hobbyist.
>at some point, electrolytics were replaced
So point is a bit vague post a pic to give us a better idea of the time frame. Values aren't very critical and manufacturers try to use the smallest value possible as it's cheaper. I would probably use a pair of 10mf @ 450v just for convenience. With that being said on older ac sets from the late 20's and early 30's that use small value caps like 1 and 2mf caps are more critical and should stick to the original values.
>When I read from the Rectifier plates I should get 1050 ohms.
Would lose any sleep over it. Check to see if the AC voltage from each plate to the chassis, should be fairly even within a few volts. Generally I look for signs of over heating like wax under the transformer on the cabinet or the transformer get hot w/o the rectifier tube plugged in after 5 or so minuets.
> Checking from the green center tap to pin 2 is 380 and pin 3 is 360.
To have the same number of turns from center to each end the inside winding is going to be shorter than the outside as it is wrapped around the inside. Longer winding = higher resistance.
> but looking for your expert advise.
[Image: http://philcoradio.com/phorum/images/smi...on_lol.gif] Just a hobbyist.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
