Madison Base upd858 won't power up

[wulff]

Hey guys I picked up a President Madison 40 SSB off eBay the clock runs as well as the light in the clock but the radio won't power up, I did the usual hook up to the 12VDC still dead. the fuse is okay as well.
I am removing the clock and installing a frequency meter in it's place.
The radio is stock with no mods (which is a good thing) I can't find a schematic online although the layout looks almost like my Washington 858's.
The previous owner said in his ad that if he kept playing with the alarm button it would come on for awhile, I find this hard to believe as if the radio 12 vdc ran through the clock and the timer was hosed I should still be able to get a power on through the rear DC input.
It was last used in the 1980's so I was wondering if anyone can think of a electrolytic capacitor that could cause a complete shut down?
I really like the looks of the Madison and would like to get it on the air as soon as possible.
Thanks in advance.

-- Tuesday, 17 March 2015, 22:53 PM --

I ordered a schematic for the Madison, but something I was wondering from my past. I have fixed several mobiles that had burned out reverse polarity protection diodes. I was wondering if someone hooked up the rear 12 VDC wrong and blew it would the power supply by-pass it? (since a built-in power supply doesn't need the diode protection. I also noticed the clock lamp working so it must be getting 12 V (I left my VOM meter at work)
The reason I wondered about the first owner messing with it is he was a kid when he last used it and he apparently lost the plug-in AC cord and shaved another one to fit. Doing the Colombo thinking, maybe he lost the AC cord and tried hooking it up with a DC source and got them reversed.
Oh, well this weekend I will try tracing the power though the radio.

-- Wednesday, 18 March 2015, 21:28 PM --

Okay, I fixed it, the funky AC cord the kid carved up would allow the AC to come on but there is a switch hidden in the AC inlet that switches the A/C to D/C if it makes contact.
I missed it the first time because my 12 VDC power supply wasn't working!
So, please stop bombarding my post with possible solutions!!!! LOL

-- Thursday, 19 March 2015, 7:50 AM --

This is info Madison users should keep in mind, I have seen posts where people were looking for replacement cords and were told to just use a standard 2 -prong AC cord but these dedicated Madison cords have a 'bump' to push a switch to switch from AC to DC depending on if the cord is present. Since this is a base only, I soldered the orange wire from the AC switch (H409) to the fuse holder and run it off the internal power supply.
Just a bit of info if you own a Madison Base.

[443 Arizona]

hello wulff, several of us have the madison, i am familiar with the clock/time powered switching, it is a feature i usually avoid.
i use to have it set to come on in the morning in place of an alarm clock.
the cord problem i am unaware of so thanks for that tidbit.
i have other problems with mine thou. have not messed with it since.

[MDYoungblood]

Now that you mentioned it I remember (actually don't remember the brand, think it was a Craig base) another radio that a funky AC jack with a switch, it would disconnect the clock when unplugged and using the DC cord.

3's

Greg

[wild willy]

I have one that had the same problem. Clean the clock area, and contacts very well ( and be careful) this may help. It worked for mine, thanks to The CB Doctor . I hope it works for you. If the radio is stock, I wouldn't cut anything out. It will help keep the value if you leave it looking original. Just my own opinion. Good Luck!

[443 Arizona]

i would rather they skip the clock alltogether, its a radio byjimaney!