The Amateur Amateur: 220 MHz, Act II
By Gary Ross Hoffman, KB0H
The fabricated standoff using angle irons as cross beams
I'm still intrigued by the 1.25 meter band (aka the 220 MHz band). I'm
not sure why. It may be because a couple of much more experienced
hams lauded its qualities back when I was a newbie. It might have
been because it was somewhat inaccessible at that time. Or maybe it
just that it wasn't cluttered up yet. Whatever the reason, I continue
to play around with the band (see my column "220")
and try to encourage others to do so as well.
Apparently I was not the only aficionado of the band in the St. Louis area. My
friend Max, K0AZV talked to Roger, K0GOB and obtained permission to
run a weekly net on Roger's 220 MHz repeater. I was gratified not
only that Max had made the effort, but also because he chose the one
220 MHz repeater that I could actually reach.
But participation has been light. I guess that's to be expected, it's
still early days. Nevertheless, I did what I could to prod the local
operators into giving 220 a try. Using a rare windfall of cash, I
bought about a dozen BCH-220 hand held radios from BridgeCom
then handed them out as gifts to the net control operators, and as
door prizes, at a St.
Louis Metro ARES
That caused a brief spurt of activity on Max's net, but I think many of
the BCH-220 recipients were just a tad out of range of the repeater.
I am hopeful, though, as Max's net still garners a few participants,
and other owners of local 220 repeaters are looking to upgrade to
My brother Chris, K1KC gave me a BCM-220 for Christmas (thank you!).
This is BridgeCom's monoband 220 MHz mobile rig. I disconnected my
Alinco DR-235T and gave it to Max, who had been using a hand held up
to that point. I set up the BCM-220 as my new shack 220 station, and,
full of unreasonable expectations but a boatload of hope, gave it a
It worked. It reached Roger's repeater better than the Alinco did. But,
of course, it didn't perform miracles. I could now also reach the St.
Louis and Suburban Radio Club's
220 repeater as well, but just barely. I had to admit to myself that
my lousy location and even lousier antenna system needed to be
addressed. I couldn't do anything about the former, but I could at
least replace the Diamond D130J multi-band discone that I was using
with an antenna specifically designed for the 220 band. There were
just two things that stood in the way:
Over time my health did improve to the point where I thought I could take
on the second problem, which I did (see my column "Two Retirees on the Roof").
The discone, down but not out
Okay, if you didn't bother to follow that last link, shame on you. In
summary, what happened was that I convinced a friend of mine, Bob
(no call sign, he's not a ham.. just a nice guy) to climb up on my
roof with me and replace six rusty nut-bolt pairs with six new bronze
pairs. It took an hour and I was completely worn out, but we got the
job done. We decided to take a breather and get on with real life for
a while before tackling the rest of the project.
In the meantime, I haunted my shack, trying to figure out what else I
could do to improve my 220 MHz operations. One thing that drew my
attention was that the coaxial cable that I was using was longer than
it needed to be. Some of the excess was coiled up in my shack just
before it reached an antenna switch. From my early training, I
remembered that the higher the frequency, the greater the signal loss
over long runs of coax. How long was that coax, anyway? I most likely
bought it as a stock item with the connectors already installed. Was
it 50 feet long? Probably longer. 100? 200? A million? I wasn't sure.
Could chopping off five or ten feet make a difference?
I decided to give it a try. And believe me, I really had to convince
myself to do so. I hate installing connectors.
I'll skip the sordid details about me putting on a new PL-259 connector. I
don't want to cause you to cringe, I managed to remove ten feet of
the coax, and saved another three feet by bypassing the antenna
switch. It was no longer leading to any radios other than my 220 rig.
Did it work? Well, it seemed
like it did, in that I was able to get a better signal into and out
of the St. Louis and Suburban Radio Club 220 repeater.
Until I tried it again later. This time I couldn't reach it at all.
I found out later that it was the SLSRC repeater that was at fault,
though, not my equipment. The club's president told me that the
machine had problems and was scheduled to be replaced next year.
I asked Bob if he was interested in another "rooftop adventure",
and he said yes. Before he arrived at my house, I dragged out my
aluminum fold-up ladder and lubricated its stiff joints. I still had
a hard time budging them. (It may be that it was my
joints that needed lubricating.) I needed Bob's help to pop
everything into place.
It had been hot the last time we were up on the roof, but this time it
was chilly and breezy. It slowly warmed up as we worked.
So, here's a quick description of what we were working on:
A tripod firmly mounted on the roof
Fifteen feet of steel mast secured in the tripod
A home brew pair of "cross beams" acting as standoffs for
a pair dual band antennas, located about five feet up the mast
A multi-band discone antenna at the top of the mast
You don't happen to see a metric bolt anywhere, do you?
We had removed the rusted nuts and bolts on the tripod during our last
visit, so we knew that we could easily slide the mast out of the
tripod. But before we attempted that, we needed to remove the cross
beams. If we tried to lift the whole thing out as a unit, it would
have been too unwieldy to control, resulting in:
Damage to the roof
Damage to the antennas
Damage to the cross beams
Damage to us
Not necessarily in that order.
So, we started working on the cross beams. Now, in the past, I had done
this sort of thing by myself (with my safety officer on the ground
nervously thumbing 9-1-1 on her phone over and over). But back then,
I had always treated the cross beams and the antennas mounted on them
as separate items. But with two of us on the roof this time, I
figured we could remove the cross beam / dual band antenna
combination as a single unit.
Naturally, it was a pain.
The main problem was that the cross beams were held tight against the
mast by two u-bolts. And the u-bolts had unreasonably long legs.
(Hey, I said
this was a home brew contraption. Those were the only u-bolts I could
find that fit!) When we started removing the nuts keeping the u-bolts
tight, we had to unscrew, unscrew, unscrew, unscrew. It took ages
to get those nuts down the legs of the u-bolts. (No, power tools
would not have fit.) All the while, the cross beams got looser and
looser, necessitating a spare hand, arm, or shoulder to hold
everything in place.
We eventually got the cross beams and antennas down without damaging
The mast came out easily, and we laid it down. The next task was to
remove the discone antenna.
Man, that thing put up a fight! We had to disassemble it practically down
to the molecular level before we could even get ot off the mast. But
we finally did, and began mounting my new Tram-Browning 220 MHz
antenna. It wasn't complicated, but it was more laborious than I had
And that's when fate caught up with us. I lost one of the bolts.
been there, I had counted all of the hardware several times. I was
puzzled, because whenever a loose nut, bolt, screw, or tool starts to
escape, I can hear it go skitter-skiiter-skitter down the slope of
the roof. This time there was no tell-tale skittering.
We searched the roof, our clothing, containers and everything else in
sight, but the bolt was not to be found. I told Bob that I had
numerous spare nuts and bolts in my basement, but the missing one was
metric. I was pretty sure I didn't have any of those.
As it happened, I had one and it was the right size.
Amazing. Absolutely amazing.
Umm, did you want that to be off center?
We finished up mounting the new antenna, connecting it to the coaxial
cable, weatherstripping it, and then getting the mast back into the
tripod. It was at this point I realized that I'd forgotten to bring a
level with me.
"Looks straight to me," said Bob, clearly as tired as I was, so we
tightened the mast to the tripod and took a short breather.
Not quite rejuvenated, we picked up the cross beam assembly and struggled
it into position. We put the u-bolts in, then screw, screw, screw,
screwed the tightening nuts until everything was nice and snug.
I breathed a sigh of relief, knowing that all we had to do now was
clean up and get the heck off the roof. Until I heard Bob say....
"Um, Gary? Did you mean for the cross beams to be off center?"
I took a few steps back, and....
Bob was right. The cross beams were
off center. One dual band antenna was much too close to the mast,
while the other was far away.
So.... unscrew, unscrew unscrew, etcetera, etcetera. We had to do the whole
cross beam assembly all over again.
It seemed like an eternity, but we got the job done. We washed up and
went to Burger King for a celebratory meal.
While munching on a french fry, Bob said, "You seemed to have a lot
more stamina this time."
That really surprised me, but he was right. I pooped out after one hour
the last time we were up there, and I had fairly oozed off the roof
as a dying mass of protoplasm. This time we were up there three times
longer, and while pretty tired, I was not near-death tired like I was
before. That cheered me up a lot. It meant that I was recovering from
my earlier long-term illnesses (and, truth be told, cures).
The new antenna worked fine, but again, no miracles. I think I'll need to
jack my house up 50 feet to achieve one of those.
Somewhat later in the day, I was down in my shack cleaning the trash that had
accumulated in my tool bag. Perhaps not too surprisingly, I found (1)
a level, and (2) the missing bolt.
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