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Biggdog259
Posted on Saturday, October 04, 2003 - 3:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

is there any thing i can do to get the receive back up on my 101ex? Biggdog
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Kc0gxz
Posted on Monday, October 06, 2003 - 11:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Biggdog259

A good place to start is to get all of the receiver tubes checked. They don't last forever.

Jeff, kc0gxz.
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Scrapiron63
Posted on Tuesday, October 07, 2003 - 8:39 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey has my memory completly gone here, I was thinking the 101 series just has 3 tubes, a driver and the two finals, and the rest is solid state. Am I thinking about the wrong radio.
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Kc0gxz
Posted on Tuesday, October 07, 2003 - 2:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Scrapiron63

You just may be right. It's possible that it may be me that's thinking of the wrong radio. It's been a long time since I was in a FT-101 anything.

Jeff, kc0gxz.
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2600
Posted on Saturday, October 11, 2003 - 11:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Just on a hunch, unscrew the clear plastic pilot-light lens from the rear panel near the antenna socket. The bulb inside is in fact a FUSE meant to protect the reciever's input stage from surges. If the filament in the lamp has blown, it will reduce but not kill the receiver's sensitivity. Because the metal base of the bulb creates a small capacitor, even a blown bulb will make the receive signals "come up" a little when you plug it into the socket. Check the bulb for continuity, and clean the contact button in the socket with a Q-tip moistened in rubbing alcohol. The bottom contact on the lamp is made of tin/lead solder and will tarnish with the passage of time, so clean it too. That can reduce the receiver's signal level if the tarnish gets too thick.

There is a long list of other breadowns that can occur in a 25 or 30-year old radio, but they don't get any cheaper or easier to try than these two.

Best way to keep the FT-101 receiver from becoming 'crippled' is to unplug it from the antenna coax when it is not in use. One customer of ours had a mysterious breakdown in his FT-101 receiver, the first RF stage MOSFET transistor broke down. Didn't seem so mysterious the next time. Seems a "WorldWide" operator drove by his house keying too many KWs. He was at home the second time this happened, and mentioned that every electrical device in the house was being bled while this fella drove by. Just to sweeten the pot, his beam was pointed at the road just then.

Now he unplugs the coax from the 101 when it's not in use. Hasn't experienced a MOSFET failure since.

73
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Biggdog259
Posted on Sunday, October 19, 2003 - 4:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thank you one and all,will try the things suggested but the recive fuse is gone,wonder where i could get another one???????
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Crafter
Posted on Sunday, October 19, 2003 - 10:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

When I talk on my voyage my bulb lites up in the back of my 101 on 10 meters. First time it was doing that really freaked me out, now I switch it to the dummy load when its on stand-by.
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Pig040
Posted on Monday, October 20, 2003 - 10:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Bigdog,
My recieve went on my 101EE, I could only recieve close local stuff, a transistor was shot. It was something called mosfet 35k40, I dont know what that means I am not a tech, but after it was replaced the trusty 101 is back to normal.
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Bruce
Posted on Monday, October 20, 2003 - 12:42 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

MOSFETS work much like tubes. In the early 70's the 40637 was king and the 3sk40 was the japs answer to it. The dualgate fet made a ideal mixer signal in gate 1 injection in gate 2 much like a pentagrid mixer did years before. In my ft-620 they used fets in the frount end and at 50 mhz they worked very well. Today GASFETS have replaced MOSFETS mainly because they cost about the same and GASFETS have lower internal noise.
mosfets are easly damaged by static and the 40673 has protection diodes grown into the device many of the jap ones did not.....and static will blow them. This is a great RF amp and mixer slowly losing out new technoligy .........but dont count them out.
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Crafter
Posted on Monday, October 20, 2003 - 6:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Easy fix its the silver thing in the green plug-in board. Dont get much easier than that .
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Biggdog259
Posted on Friday, October 24, 2003 - 6:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Crafter is it the tall silver thing on the green plug-in board ?????????????????

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