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I have a faulty MFJ-259, the early model I believe. When I power it up, the power light doesn’t illuminate, and the meter needles hit the right hand end stops. I immediately power down as I guess this isn’t an encouraging sign.

Before I take the thing apart in earnest, any ideas anyone what he problem might be? Anyone seen this kind of thing before with an MFJ-259?

Any hints gratefully received.

Cheers Tim.

Mike Waters
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user2555403
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    One data point: My MFJ259B has a (dirty?) bandswitch with similar symptoms. Pressing down very hard on the bandswitch knob makes it work OK. – Cecil - W5DXP Jan 13 '19 at 17:09
  • Tim, do you have the MFJ-259 manual? (I could not find one online [**except here**](https://www.w8ji.com/mfj-259b_calibration.htm). I have a 259**B**, and mine has no power light. – Mike Waters Jan 13 '19 at 17:58
  • @w5dxp Assuming that the contacts are not gold plated, [DeoxIT D-100L](http://store.caig.com/s.nl/it.A/id.2912/.f) is your friend, and maybe Tim's too. – Mike Waters Jan 13 '19 at 18:53
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    @Mike, it's a potted switch on the other side of the PCB. – Cecil - W5DXP Jan 13 '19 at 19:53
  • @w5dxp If it's not hermetically sealed, perhaps we can get enough liquid inside. D5 has less viscosity than D100. – Mike Waters Jan 13 '19 at 20:07
  • What does the LCD display show? Perhaps you can put a photo in your question. – Mike Waters Jan 13 '19 at 20:15
  • Manuals for pretty much all of MFJ's products can be found at http://www.mfjenterprises.com/support.php – imabug Jan 13 '19 at 20:36
  • @Mike Waters hi mike, you can get deoxit here in Australia but it’s hideously expensive. As has been pointed out the switch appears to be potted so don’t know how I’d get in. Good advice from all, I’ll investigate further. Tim VK4QP – user2555403 Jan 14 '19 at 11:06
  • My switch shaft moves in and out when I push on it and that's probably loose contacts rather than dirty contacts. – Cecil - W5DXP Jan 14 '19 at 13:26

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No power light could just be a burned out bulb or dead LED (I have a 259B...don't recall if the power button ever lit up). If you don't have anything connected to the antenna connector, then it's perfectly normal for the SWR meter needle to go all the way to the right because it's indicating a high SWR. Put a 50 ohm dummy load on the analyzer and see what happens

imabug
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