[Hallicrafters] Close Call With a SX-100

[Mark Shaum]

Greg asks:

>While we are on subject of  rf switching etc. what ever happened to the
>"patch panel"? This used to be a box with all your radio coax and and
your
>antenna coax meet up into a double row of SO 239's. When you wanted to
>change bands or rigs you just played old time telephone operator and
moved
>the patch to the stuff you wanted to mate up. Simple and  cheap
>73's
>Greg
>WA7LYO

It's still in use here, although I use switches and relays rather than
patch cords. Many shacks that have such a proper grounding setup to
protect against lightning damage.  A nice large single point ground
plate through or over which where ALL incoming wires to the shack must
pass.  Antenna, rotor, telepone, TV, AND main AC power all come here
first where they are appropriately surge-protected or grounded to the
single plate.  The plate then exits the wall to a good ground system
that is also separtely tied to your service entrance ground.   Having
ALL wires that enter the house (except mains AC which is pretty well
fixed where it is) goes a long way to prevent future damage.  At one
point a few years ago I had everything hooked up as described EXCEPT the
underground telco twisted pair.  Guess which route the lightning took.
It belew through one of those PC style surge suppressors with RJ-11
jacks for the modem, carbonizing the innards, passed through a PC in a
different room into the AC wiring of the house and proceeded to fry many
things before it tripped a pair of 20A line breakers in reverse on its
way out to the service ground whole-house suppressor.

I use coax switches and relays that ground unused antennas, but even
then disconenct all coax leads from the panel during severe storm
periods at the entry plate.  My only wish at this time is that I used
something rugged enough but easier to connect/disconnect under the desk
at floor level than PL-259's and barrel connectors.

In the case of accidentally routing xmit RF direct to a receiver,
protection diodes won't help much.  However, they might if you have a
small fuse in-line (one of those grain-of-wheat lamps works) which would
go open before the diodes failed due to the large amount of RF.  My JPS
and MFC antenna noise cancellers have a small light bulb in series with
the noise antenna input to protect against large RF doses from nearby
xmit antennas.  My old Yaesu FT980 also has one in the main receiver
antenna path, I didn't know that until the RX went dead one time and I
had to figure out why.

73!
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Mark Shaum K9TR
email: k9tr at dtnspeed.net
http://www.qsl.net/k9tr
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