Hi All Again, well I got the tar out of the Condenser side of the 37 Power Supply and was shocked by all of the stuff they stuffed into it. A daul choke rated at 1600 ohms, one 500 ohm choke and around nine capacitors. Problem is the schematic shows the chokes and I can probably get replacement for them but why is there such a large difference in the capacitors? I'd like to rebuild it but I'm soooo confused is anybody out there familiar with these power suppies. Thanks a Million, George T

George

Should go by circuits at Atwater Kent Info site:

http://www.atwaterkent.info/TechData/Images/SM2808_060.gif

The supply does use two filter chokes. It was less expensive that using large value filter caps. I replace the filters with 10 mf @ 450 volt caps.

The third choke is a plate load for 71A tube. If damaged you can use a small output transformer without connecting the secondary.

Norm

:Hi All Again, well I got the tar out of the Condenser side of the 37 Power Supply and was shocked by all of the stuff they stuffed into it. A daul choke rated at 1600 ohms, one 500 ohm choke and around nine capacitors. Problem is the schematic shows the chokes and I can probably get replacement for them but why is there such a large difference in the capacitors? I'd like to rebuild it but I'm soooo confused is anybody out there familiar with these power suppies. Thanks a Million, George T
:

Hi Norm, so I can put in two 10mf/450 electrolytics in place of the two filter chokes and hook it up the same with the negative going to center and install the caps above them going to ground. That is a chassis ground right. The speaker choke looks like it survived so I should be OK there. Going to power up the transformer can today and see what is working on it. Now I know why I like the AA-5's. Thank You So Much For Your Help. George T

:George
:
: Should go by circuits at Atwater Kent Info site:
:
:http://www.atwaterkent.info/TechData/Images/SM2808_060.gif
:
: The supply does use two filter chokes. It was less expensive that using large value filter caps. I replace the filters with 10 mf @ 450 volt caps.
:
: The third choke is a plate load for 71A tube. If damaged you can use a small output transformer without connecting the secondary.
:
:Norm
:
::Hi All Again, well I got the tar out of the Condenser side of the 37 Power Supply and was shocked by all of the stuff they stuffed into it. A daul choke rated at 1600 ohms, one 500 ohm choke and around nine capacitors. Problem is the schematic shows the chokes and I can probably get replacement for them but why is there such a large difference in the capacitors? I'd like to rebuild it but I'm soooo confused is anybody out there familiar with these power suppies. Thanks a Million, George T
::
:
:

You would want to keep the original filter chokes if at all possible. Install the two 10MFD in place of the old filter capacitors. The ground point is that center nut that's marked ground on the schematic.

:You would want to keep the original filter chokes if at all possible. Install the two 10MFD in place of the old filter capacitors. The ground point is that center nut that's marked ground on the schematic.
:
Hi Warren, The filter choke is shot on the one side but OK on the other. I thought you would have to use a resistor or another filter choke to replace it. The filter choke in this unit is double sided, between the two sides it needs to come up to 1600 ohms. The 500 ohm speaker choke survived so I'm good there. Thank You, George T

The filter chokes are not only for filtering, but are also used as dropping resistors. Without one of the filter chokes you would need to add some resistance to make up for it. Measure the existing choke, and use a resistor of the same value in place of the bad choke. I would use the good filter choke as the first one from the rectifier, the resistor for where the 2nd one would be. The use of two 10 MFD capacitors might be enough, but without the choke you could use 22 MFD for the second capacitor to make up more for the lack of filtering. Do you have this article about rebuilding power supplies?

http://www.atwaterkent.info/Articles/AKPower.pdf

:The filter chokes are not only for filtering, but are also used as dropping resistors. Without one of the filter chokes you would need to add some resistance to make up for it. Measure the existing choke, and use a resistor of the same value in place of the bad choke. I would use the good filter choke as the first one from the rectifier, the resistor for where the 2nd one would be. The use of two 10 MFD capacitors might be enough, but without the choke you could use 22 MFD for the second capacitor to make up more for the lack of filtering. Do you have this article about rebuilding power supplies?
:
:http://www.atwaterkent.info/Articles/AKPower.pdf
:
:
Hi Warren, No I didn't have that article but it looks like it's the ticket. So just to be sure I really don't neet the 2 filter chokes if I use the 22mfd 450 volt electrolytics, and I can use the original Speaker choke which survived. Wish I would have had that article before I took a torch to the metal can to melt the tar. What a mess. LOL Thanks Again, George T.