Problem with MFJ-986 and 1N34E
 

I have a problem with my MFJ-986

The two 1N34E of the control power and the system of TOS meter have qrt
.....two time. I don't know the reason but it is not about too big power or
some thing like that....Not in use or in qso. I think it is with statics
(when there is a storm, or snow..or ??) I have also put 2X1N4148 and also
go qrt...

I have put two 1N4001 but all the measures of power or swr are wrong... I
cannot tune the god power. But they have no qrt for the moment !!

Is there anybody who have the same problem ?? And what kind of pin can I put
in place of the 1N34E ?? to find again the same characteristic of the MFJ
986 at the beginning ?? and be much powerful than the 1N34E ??

Thanks for your help and excuse me for bad english. I hope that you can
understand me !

Best 73

Frank **F6BLP**

On Tue, 29 Jul 2003 18:13:33 +0200, "Francis Pinson"
wrote:

I have a problem with my MFJ-986

The two 1N34E of the control power and the system of TOS meter have qrt
....two time. I don't know the reason but it is not about too big power or
some thing like that....Not in use or in qso. I think it is with statics
(when there is a storm, or snow..or ??) I have also put 2X1N4148 and also
go qrt...

I have put two 1N4001 but all the measures of power or swr are wrong... I
cannot tune the god power. But they have no qrt for the moment !!

Is there anybody who have the same problem ?? And what kind of pin can I put
in place of the 1N34E ?? to find again the same characteristic of the MFJ
986 at the beginning ?? and be much powerful than the 1N34E ??

Thanks for your help and excuse me for bad english. I hope that you can
understand me !

Best 73

Frank **F6BLP**



Hi Frank,

I think you have a problem with static electricity or lightning. The
1N34 diodes are very sensitive to voltage. They will fail if the
voltage gets too high, like with a nearby lightning strike. Best idea
is to unplug the antenna lead when you're not using the radio.

The 1N34 is a Germanium diode. It is used because it has very low
forward voltage drop. You might substitute a 1N60, but probably
better to order replacement 1N34's from MFJ. None of the other diodes
would be suitable, because they are all Silicon.


73 de Leigh W3NLB

On Tue, 29 Jul 2003 18:13:33 +0200, "Francis Pinson"
wrote:

I have a problem with my MFJ-986

The two 1N34E of the control power and the system of TOS meter have qrt
....two time. I don't know the reason but it is not about too big power or
some thing like that....Not in use or in qso. I think it is with statics
(when there is a storm, or snow..or ??) I have also put 2X1N4148 and also
go qrt...

I have put two 1N4001 but all the measures of power or swr are wrong... I
cannot tune the god power. But they have no qrt for the moment !!

Is there anybody who have the same problem ?? And what kind of pin can I put
in place of the 1N34E ?? to find again the same characteristic of the MFJ
986 at the beginning ?? and be much powerful than the 1N34E ??

Thanks for your help and excuse me for bad english. I hope that you can
understand me !

Best 73

Frank **F6BLP**



Hi Frank,

I think you have a problem with static electricity or lightning. The
1N34 diodes are very sensitive to voltage. They will fail if the
voltage gets too high, like with a nearby lightning strike. Best idea
is to unplug the antenna lead when you're not using the radio.

The 1N34 is a Germanium diode. It is used because it has very low
forward voltage drop. You might substitute a 1N60, but probably
better to order replacement 1N34's from MFJ. None of the other diodes
would be suitable, because they are all Silicon.


73 de Leigh W3NLB