Hi all...
This is a bit long and deals with getting setup for SO2R...
A week or so ago I posted a couple of open-ended questions here
concerning my plans to convert my station to SO2R...Really, I needed
some basic information to try and get my brain wrapped around all the
hardware issues involved, including antenna switching, bandpass
filtering and SO2R controllers...The responses were numerous and greatly
helpful...Thanks to everyone who helped me out...Information is king,
and I received a ton of it...
It appears that there are others who are trying to sort all this SO2R
stuff out too, as I've received a dozen or so emails in the last couple
days asking for a summary of what I found out...
So, I'll try to sort out and summarize what I've been told and what I've
read...I'm no expert at this stuff , in fact I haven't converted to SO2R
yet, but I now have enough information to make some decisions about what
I need to do...Maybe this will help others wrestling with the same issues...
Here's what I found out:
For most SO2R setups you will need:
-Banpass filters for each radio
-A switching unit(s) for your antenna system
-Band decoders for each radio
-A SO2R controller
-Patience...Operating SO2R effectively takes practice
-$$$...It can get expensive, depending on what you do...
BANDPASS FILTERS
Unless your antennas are well physically seperated, you will likely need
some bandpass filters to protect Radio B's receiver while transmitting
on Radio A. This was the biggest issue that most had trouble resolving.
You can buy single-band BPF's and multi-band BPF's. Dunestar Model 600
Multi Band Remote Switched Bandpass Filters
<http://www.dunestar.com/model600.htm> seemed to be the choice of
most... $339 US each...
The I.C.E. Model 419A Combination Bandpass Filter was also
popular...http://www.arraysolutions.com/Products/ice/filtersrf.html#3
These are $228 US each...
I did some testing in my own shack and found very little cross-band
interstation interference with my MP and Mark V at 100/200 watts...There
was heavy same-band interference...My beam and dipoles are all within
100 feet of each other...My amp is busted right now so I didn't try high
power...However, on the advice of those who know, and my better
judgement, I'll be putting a BPF on each radio...Keep in mind that BPF's
can eat 15% to 20% of your output power...Better than a blown
receiver...I tend to be cautious with this stuff...
Lots of hams also use coaxial "stubs" for additional filtering protection...
ANTENNA SWITCHING
Lets just say that there are thousands of choices and possible
combinations here...You will need some way to switch antennas between
radios...This can go anywhere between fully manual to fully
automatic...By far the most popular choice of switches is the "Six Pack"
by Array Solutions...It seems to offer the best protection for your
radios...It handles 6 antennas and two
radios...http://www.arraysolutions.com/Products/sixpak.htm Cost - $400 US.
Another popular choice is the Top Ten Devices Six Way Antenna Relay
Box...this one has 6 antenna outputs but only one
input...http://www.qth.com/topten/sixway.htm Cost - $125 US
Antenna switching can be fully automatic if you employ band decoders
(see below) to control the antenna switches...
You, of course, can get along very well with two manual coax switches,
if you have enough antennas to assign to each radio...Again, the
possibilities are endless...I've chosen the SixPack...
BAND DECODERS
You can control both the bandpass filters and antenna switches with a
Band Decoder on each radio...These units sense what band the radios are
on and switch the filters and antennas accordingly...Two brands
mentioned to me were the Top Ten Devices Automatic Band Decoder (Seemed
to be the favourite of most) http://www.qth.com/topten/sixway.htm and
Array Solutions DBS-1 Band
Decoder...http://www.arraysolutions.com/Products/banddecoders.htm#top%20of%20page
There are package deals offered by some as well...Array Solutions has
several packages, including "#4" - a SixPack antenna switcher, two DBS-1
band decoders, 2 ICE 419 filters and some cabling for $1,205
US...http://www.arraysolutions.com/Products/pricelist.htm#SixPak -
Scroll down until you see "Packages"...This would appear to give you a
good, fully automatic system...
SO2R CONTROLLER
This unit handles all the audio, microphone, keyer, headphone etc
switching between the two radios...
There are 3 well known off the shelf controllers available...Top Ten
Devices "DX Doubler" http://www.qth.com/topten/index.htm , Array
Solutions "SO2R Master"
http://www.arraysolutions.com/Products/so2r.htm#top%20of%20page and the
W5XD MK-1100 Multi Keyer http://www.writelog.com/SO2R/w5xd_multikeyer.htm
I'm still undecided about this as all 3 got high marks...One thing to
keep in mind is that the W5XD Keyer is designed for use with Writelog
but apparently works fine with other software...Some hams have built
their own controllers, others don't use one...
From my own personal perspective, the system that has caught my eye is
the Package #4 (see above) from Array Solutions...It has most everything
you need to get an automatic and safe setup...It comes highly
recommended from people who use the gear...
Some other very useful and informative sites:
http://www.arraysolutions.com/Products/so2rbasics.htm
http://home.columbus.rr.com/jmaass/Radio/K8ND_SO2R.htm (GREAT pix of
SO2R setups at K8ND's site)
http://www.k1ttt.net/technote/tworadio.html (some excellent reading
from users of various products at K1TTT's site)...
I basically spent a week searching the internet, reading emails, asking
questions etc...I could spend two months and still not see everything
that's available...There are numerous other products available, but the
ones I mentioned above wewre BY FAR the most popular with the kind folks
who took the time to tell me their stories...I know there are other
issues, products, methods, scenarios...Every shack is different...My
advice is to read everything you can get your hands on and ask questions...
That's what I found out, I hope it's accurate and hope it helps if you
are thinking about going the SO2R route...See you later in the summer
after my shack renovations are completed...
73, Scott VE1OP
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