MTX8000 Won't Power Up

Rayjk110 · Post by **Rayjk110** » Sun Apr 08, 2007 12:12 pm

I've got a M1 MTX8000 that won't power up when a battery is attached. I'm guessing the internal fuse is probably shot. Where would this fuse be, or at that, look like. Thanks.

BTW, There is no water damage to this radio or anything like that.

Post by **wavetar** » Sun Apr 08, 2007 4:08 pm

Look on the RF board, right next to the power pins...it's a small rectangular surface mount glass fuse with what looks like a silver "H" in it. Sometimes you can see the break in the "H", sometimes you can't.

Todd

Rayjk110 · Post by **Rayjk110** » Sun Apr 08, 2007 4:41 pm

Yeah, theres a small break in the "H" Like |-\-| (where the \ represents the break) Really small, too.

Do you have the model # for the replacement fuse?

Thanks .

Bruce1807 · Post by **Bruce1807** » Sun Apr 08, 2007 5:32 pm

6505757V01

Post by **VE9MP** » Sun Apr 08, 2007 6:43 pm

If you wanted to be hamsexy, assuming this isn't for any public safety use or anything, a temporary solution is just making a little solder blob from the top to the bottom of the fuse...

Post by **alex** » Sun Apr 08, 2007 6:50 pm

Well, the important question is always - why did the fuse blow in the first place... You may damage the radio further.

Not that it's going to cost you much to fix - but may not be a bad thing to investigate.

-Alex

Post by **VE9MP** » Sun Apr 08, 2007 6:57 pm

I've only blown 1 pico fuse in the past, it was when I grabbed a battery right off the rapid charger and threw it on the the radio within half a second of removing it from the charger.

You wouldn't think that would blow a 4 or 5 amp fuse, but it did...

Rayjk110 · Post by **Rayjk110** » Sun Apr 08, 2007 8:06 pm

I'm not sure how exactly it was blown. It was given to me this way in a bin of other working MTX radios...so I cant for sure say.

After being fixed it would be slaved as an RX radio only for a project...so not that it would be drawing tremendous current anyhow.

Post by **wavetar** » Mon Apr 09, 2007 4:30 am

Most times, there's a small post which breaks off the rear chassis & shorts things out. This was fixed in later designs.

99.9% of the time, you replace the fuse & you're good to go.

Todd

Victor Xray · Post by **Victor Xray** » Mon Apr 09, 2007 6:08 am

<hamsexy>

Just put a glob of solder over the fuse & call it done

</hamsexy>

Rayjk110 · Post by **Rayjk110** » Mon Apr 09, 2007 7:13 am

Well, the only post broken off of the Jedi Chassis on this raido is the lower left battery tab, not that that should affect anything, though.

hareless · Post by **hareless** » Mon Apr 09, 2007 8:19 am

Alex said there may be other reasons for the fuse to be blown.I can think of two-you may have lost the rf pa or the audio output stage.In either case the fuse will go tu.

Post by **wavetar** » Mon Apr 09, 2007 11:59 am

Rayjk110 wrote:Well, the only post broken off of the Jedi Chassis on this raido is the lower left battery tab, not that that should affect anything, though.

Check the top of the RF board, near the antenna connector. If there's a small through-hole in the board, then there should be a corresponding post on the chassis which slides through the hole to hold the board in place. This is what commonly breaks & blows the fuse. If the RF board has an open notch instead of the hole, then it's the newer version & the broken post isn't the problem. I will say I've seen plenty of the fuses blow for no apparent reason...replace them & the radio works fine.

Todd