[CQ-Contest] SO2R technical questions

Mike & Coreen Smith VE9AA ve9aa at nbnet.nb.ca
Tue Jan 20 16:40:25 EST 2015

How can I tell if I have too much energy at the input of "radio 2" when
transmitting on "radio 1" ?


I've done a few DXpeditions  and field days (CY0AA, CY9AA etc.) and we had
some cheapie bandpass filters and some rapidly made crappy coax stubs
(without using any kind of device other than a calculator and a measuring
tape to verify the correct lengths).

At times we  operated w/o one or both (both LP and QRO) and sure, we had
interference, but nobody blew up a rig.


Now nearly 2 decades later I am just barely dipping my toe into the SO2R
waters so with N1MM+'s help, today hooked up my Winkey to 2 rigs (IC7410 &
746) and when transmitting on a wide variety of antennas on radio one
(HF9V, A3S, Inverted L's for 80/160), and limiting radio 2 to only a ZS6BKW
as an inverted Vee (G5RV like) antenna about 50-60' away from all the
various antennas, harmonics were fair to bad, but not what I would call
severe. (no stubs, no BPF's, nuttin' but air).


CW peaks looked like around *50-60/S9 and steady dits were *40/9 if those
cheezie Icom bar-graph S-meters are to be believed. *(if I was on the exact
2nd or 3rd harmonic frequency)


Is this too much signal?


I can build some coax stubs over time...and I am working on a YCCC SO2R box
as time permits but don't have a lot of spare dough for BPF's (2 of them
would run me $1200-$1400 CDN by the time I had them in the shack)

nor a SIX-PAK(another $1k_), thus I am wondering about cutting costs going
in.  Another local tried SO2R, didn't like it and had spent many thousands.
I don't have the spare dosh, nor will I, hence my question..


If I am willing to leave the amp turned off (sigh..), and antennas will all
be separated only 50', how do I know if I have too much signal at the input
of the 'other' radio?


Oh and feel free to school me on SO2R...I have nearly googled the internet
dry, so have done lots of reading, so if you have a web page up, I've likely
seen it ;-)  Just never tried it.


Technique is what I lack.


I figured it was time.  I find myself (especially in CW contests) calling CQ
and ALT-TABBING over to check my email, surf the net, watch the greyline
maps, stare out the window , talking to family etc. a LOT in contests. 


Is SO2R the next step?


Mike VE9AA

p.s.- I will sorely miss using the amp, but if I try SO2R @ 100w and like
it, maybe I can stumble onto some cheap 419 BPF's and a 6-pack somewhere
later on.  I don't care a hoot about automation.  I like to flick the
switches manually.


Mike, Coreen & Corey

Keswick Ridge, NB


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