[Elecraft] 1N5711 Diodes

[Don Wilhelm]

Don,

Those diodes sit (electrically) right near the antenna jack, and are 
thus exposed to strong static and lightning surges.   If you operate 
when lightning is in the vicinity, they may become damaged.

Of course, if you do not disconnect your antennas when not in use, you 
are almost certainly assured that sometime during the spring and summer 
seasons those diodes will be damaged.  Also be aware that rain and snow 
induced static can pack quite a charge too, so it is best to disconnect 
the antennas when not in use no matter what the season - it protects not 
only your K2/100, but also you, your home and your family.

If you do not wish to give care to the diodes, you could replace them 
with 1N4148 diodes which are a bit 'tougher' than the 1N5711s, but you 
will sacrifice some power control accuracy at low power and the 1N4148s 
are not as flat with respect to frequency as the 1N5711s so you might 
experience some bands where the indicated power and the actual power 
differ more than with the 1N5711s.

73,
Don W3FPR

DDWEBB at aol.com wrote:
> I have just recently re-subscribed to the  reflector. So I have no knowledge 
> of what may have been said regarding the two  reference diodes, D 16,D17 in 
> the K2/100 and D1,D2 in the KAT100.
> After  building and using my basic K2 back in 2000, I decided to upgrade to 
> the K2/100  and the KAT100.
> I finished both of them about three weeks ago and was  enjoying the two 
> units. 
> In the last two weeks though I have blown these  diodes twice. Is this an 
> isolated incident?  
> Don...KA7L
>
>