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[KD0VE]

A rookie ham friend (general class) from out of state may visit the weekend of the SSB DX contest.  Thinking about setting up a 2nd station so we can both operate at least some of the time.  plenty of hardware and antennas for 2 stations.  Effort will mostly be for rookie to learn to use various DXing tools like VOACAP and spotting websites plus logging his contacts.  Could be a really fun weekend.

Antennas are hexbeam and EFHW on one feedline at rear of house and 40M monobander, 160M dipole and OCF dipole on tower to front of house sharing a 2nd feedline.  The EFHW is N/S orientation like the tower wire antennas but that could be changed to E/W to minimize potential coupling if thats a likely issue.

Just wondering what I should be thinking about to prevent any issues.

thx to anyone offering advice. 

[WA3SKN]

Pre-testing!
Separate bands, separate feeds, separate antennas, etc... but don't wait for the contest to start.
Start checking for interference issues before he gets there and the contest starts.
However, you can still operate just one radio and have fun!

-Mike.

[G8FXC]

You really need to assess the level of coupling between the two radios on all bands and antenna combinations. Set one to its lowest power output (probably 5 to 10 watts) and transmit while checking the signal level on the other in receive mode, tuned to the same frequency. It's hard to predict exactly how much signal it will take to do damage, but you should be safe up to S9+60dB - probably more. The receiver S meter may not read that high - assume that it's all linear, check the received signal level with 10W out, then do the sums to work out roughly what it would be with 100W out. If it's looking like it could be exceeding S9+60, then do the sums more carefully!

Some receivers can be damaged by as little as 0dBm coming down the cable. S9 is generally defined to be -73dBm - hence S9+70 is getting close to the point where you should begin to worry...

Martin (G8FXC)

[K1KP]

This is a huge topic often covered by the contesting community. Some short answers:
-It will depend a lot on transmit power. Running an amp will make it much more difficult.
-If the stations are on operating on different bands, bandpass filters can help. They can either be in line for both transmit and receive, in which case they need to handle the transmit power; or they can be switched in using relays or the radio's receive antenna port. Google W3NQN filters...
-Tuned stubs on the transmitter can help. They must be carefully tuned for the band or operation, and they must be changed when the transmitter QSYs. Failing to do so can damage amps/transmitters.

I've done this many times. The last tip I'll offer is this:

-Install a 1/16A fuse (that's .063A or 63 milliamps) in series with the receiver input. This fuse will blow before the receiver front end is damaged. Over the decades due to  'fog in the cockpit' I have blown dozens of fuses - but zero receiver front ends.

GL,
-Tony, K1KP

[G8FXC]

This is a huge topic often covered by the contesting community. Some short answers:
...
-Install a 1/16A fuse (that's .063A or 63 milliamps) in series with the receiver input. This fuse will blow before the receiver front end is damaged. Over the decades due to  'fog in the cockpit' I have blown dozens of fuses - but zero receiver front ends.

GL,
-Tony, K1KP

63 mA into the antenna socket is 23 dBm which is above the limit for quite a few solid state front ends - I would go for 30 mA if you can find it!

Martin (G8FXC)

[W9IQ]

63 mA into the antenna socket is 23 dBm which is above the limit for quite a few solid state front ends - I would go for 30 mA if you can find it!

Martin (G8FXC)

Don't forget about skin effect and the time required for the fuse to open.

- Glenn W9IQ

[W1VT]

My null canceller uses grain of wheat light bulbs as protective fuses.  I bought a small bag of them on ebay.

[AA7IS]

A rookie ham friend (general class) ??
There are many Extras now who couldn't solder two wires together and quite a few novices that could probably tell you about valance electrons and their function.
That statement just seems like a very weird flex on your "friend" a "mere" general lol.
Compared to a lot of others you are a Rookie for sure not even licensed for more then twenty years lol.

[KD0VE]

I specified general because so many rookie hams are Tech licenses.  In this case I recommended my friend study and take the Tech and General at the same time which he did.

[NA4IT]

And to say it, only because it has been done...

Be careful not to connect the transmit connector of one radio to the transmit connector of other radio.
The magic smoke will be expelled form at least one radio, maybe both.

(Happened at a field day one year.)