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Ok, I got this old Yaesu, and it was working good, had a problem when switched to 160 meter blows fuse, found C131, replaced it with 1000pf silver dipped mica cap...

Below it is a burned up capacitor, I mean burned up bad. I have seen notes to replace C13 (80pf 1000V) cap, as it could go bad, and wondering if it looks like a big ass electrolytic or not because the only capacitor I see in the area that various web pages have said to find C13 is C131 which is the cap to fix the 160M fuse blowing problem...

Anyway, I just need to locate this damn C13 cap in here and change it out, for some reason I have not been able to find any 80pf cap in this area, only a burned up beyond recognition electrolytic cap that I cannot figure out what it is/was for or any idea what value, see pic, please help! Thanks in advance 73.

Attached Images

FT-101-find-C13-cap-1c.jpg (173.1 KB, 10 views)

Ok, I found C13, it was under the "lip" on the edge of the chassis up against the chassis wall and had a piece of clear vinyl hose or something around so I wasn't sure what it was. It has a Yaesu part number on it, checked it with my cap meter, shows good, around 85pf.

So now I need to figure out what that burned up electrolytic capacitor is/was.... looking at schematics, it's attached to ground (chassis gnd) on one side and the other is connected to 2 large resistors, mounted to a standoff strip, has a wire going back to one of the pins of the driver tube.

Look on the Schematic for C-109, 2.2uf@450 volts on the main chassis... i think
I do not have a sch here, and the only chassis I have left is 60 miles away....

73
Jeff

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there is no dark side in the moon, really. As a matter of fact it's all dark

I am having trouble finding a full blown schematic of the PA area of the chassis, only the little part around the final output tubes...

This capacitor comes off Pin 8 of the Driver tube and goes to Chassis Gnd.

Looking for C109 on the schematics, but to no luck yet thanks.

OK, found a Sch online, go here
http://hamradio.online.ru/ftp2/man_sch_ft101.pdf
Download it.
Go down towards the bottom, shows 12by7a driver, follow the line off pin 8.

73
Jeff

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Radio-active

NASA/SOHO


there is no dark side in the moon, really. As a matter of fact it's all dark

couple of resistors, a choke, and then look for C109...see the +/_ next to the electrolytic cap...to the right and slightly below the 12by7a.

You can get a complete replacement set of caps here.Yaesu FT-101E HF Transceiver Capacitor Replacement Kit | eBay

Not bad for $35 bucks.......
73
Jeff

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Radio-active

NASA/SOHO


there is no dark side in the moon, really. As a matter of fact it's all dark

Thanks for the info Jeff, but this capacitor only goes from Pin 8 then to ground, the C109 in that schematic shows it passing through 2 resistors and a choke or something before it connects back to pin 8, so either the schematic is wrong and the part is right, or C109 isn't the right cap (though from it's large size and obviously Electrolytic composition you would think it must be). Wish someone had a radio to look inside of and confirm for me. I will keep looking for some other schematics. I think the one you posted the link to is for the oldest FT-101, (no suffix), so it may indeed have been a different schematic than my radio (the EE model, should be same as E/EE/EEX)

If I get down in the Valley this weekend, I will look, I have a E chassis in storage....just have to get down there to look at it.
The only cap I see that comes off of pin 8 to ground directly is C-8, 4700 Pf.


73
Jeff

__________________
Radio-active

NASA/SOHO


there is no dark side in the moon, really. As a matter of fact it's all dark