"Bryan" wrote in message
...
Jimmie D wrote:

Bryan wrote:
Nelson Blaha wrote:
I'm looking to build a 2m yagi, but I haven't got any money. Can I
make one out of aluminum coat hangers? I also have a 4-foot section
of
1" PVC pipe laying around, and glue, tools etc.

Nelson Blaha
Call-sign in the mail

Others presented good ideas. Ya know, an old TV antenna would make a
decent
yagi for 2m, and with people going to cable/satellite TV, you could
probably
find one for nothing or only a few dollars. Remove the elements you
don't
need, cut the remaining elements down to length, do a little rewiring
as
needed, connect your feedline, and you're good to go. If you want
vertical
polarization, redrill the boom-to-mast mounting holes 90° from
original.

I once did something similar with a 3 element 11m yagi... in about an
hour
or so including tuneup time, I turned it into a gamma-matched 6 element
2m
yagi. I used my VSWR-protected 2m rig's output indicator to indicate
proper
tuning by adjusting for maximum relative forward power.

Bryan WA7PRC



When we got cable in the neighborhood my wife was threateing divorce over
all the TV antennas I would pick up off the curb during trash day.

Jimmie

Hmm... I envision stacked arrays! ;^)
Bryan



I actually did very little with them. I didnt have my ticket yet. I put a
couple up in the attic for local TV that wasnt on cable. Still use them when
a storm takes the cable out.

Ok, here's what I tried. I cut notches in that 4' piece of PVC and cut
clotheshanger wire to the lengths found at this calculator:

http://www.csgnetwork.com/antennae3ycalc.html

This I stuck out my window on an aluminum pole (cinderblock walls are
bad). I'm suspicious of my wiring- I used very thin speaker cable to
connect a ground to the screws on my light switch plate, and to the
coax going into my radio. It doesn't perform half as well as my
current antenna- a mobile 5/8 dipole on the end of some eye-bar with
clothes-hanger groundplane radials. Guess I just need to wait until I
have some real coax, the speaker wire is probably the weak link here?
Maybe I was just pointing this yagi away from the station I was
listening to, I suppose it would be doing its job then!

Checking almost hourly for that license on the internet!

Nelson Blaha

On Jan 21, 11:06 pm, "Jimmie D" wrote:
"Bryan" wrote in messagenews:ItednTY6IOjx3inYnZ2dnUVZ_hmtnZ2d@gigan ews.com...



Jimmie D wrote:

Bryan wrote:
Nelson Blaha wrote:
I'm looking to build a 2m yagi, but I haven't got any money. Can I
make one out of aluminum coat hangers? I also have a 4-foot section
of
1" PVC pipe laying around, and glue, tools etc.

Nelson Blaha
Call-sign in the mail

Others presented good ideas. Ya know, an old TV antenna would make a
decent
yagi for 2m, and with people going to cable/satellite TV, you could
probably
find one for nothing or only a few dollars. Remove the elements you
don't
need, cut the remaining elements down to length, do a little rewiring
as
needed, connect your feedline, and you're good to go. If you want
vertical
polarization, redrill the boom-to-mast mounting holes 90° from
original.

I once did something similar with a 3 element 11m yagi... in about an
hour
or so including tuneup time, I turned it into a gamma-matched 6 element
2m
yagi. I used my VSWR-protected 2m rig's output indicator to indicate
proper
tuning by adjusting for maximum relative forward power.

Bryan WA7PRC

When we got cable in the neighborhood my wife was threateing divorce over
all the TV antennas I would pick up off the curb during trash day.

Jimmie

Hmm... I envision stacked arrays! ;^)
BryanI actually did very little with them. I didnt have my ticket yet. I put a
couple up in the attic for local TV that wasnt on cable. Still use them when
a storm takes the cable out.

I'm sure it's not much of a performer, nelson. If you're using speaker
wire as your feeder, it's going to be horribly mismatched. Your trx
expects to see 50 ohm on the antenna, and (though I'm not certain) I'd
be willing to bet that your speaker wire is either much higher or much
lower. At best, this will give terrible performance. At worst,
potentially blow up the output stage of your rig.
RG58 is the coax you need. It's cheap, sometimes free. It's the same
stuff old 10base2 networks used to be wired with, so a visit to a dump
will probably turn up loads.

" I'm sure it's not much of a performer, nelson. If you're using speaker
wire as your feeder, it's going to be horribly mismatched. Your trx
expects to see 50 ohm on the antenna, and (though I'm not certain) I'd
be willing to bet that your speaker wire is either much higher or much
lower. At best, this will give terrible performance. At worst,
potentially blow up the output stage of your rig.
RG58 is the coax you need. It's cheap, sometimes free. It's the same
stuff old 10base2 networks used to be wired with, so a visit to a dump
will probably turn up loads.


He did say he was using coax, the speaker wire was just a ground, which
won't really be doing very much at vhf, so that is not the problem.

73
Jeff

Actually, I'm sorry to say Jeff was right. For the sake of experiment
I had connected with speaker cable more than just the ground.
Basically, I connected speaker wires to the contacts on my mobile NMO
mount. The NMO mount had coax running back to the radio. I knew
transmitting like that was a pretty bad idea (illegal anyway), and that
I needed to get a proper wiring eventually, I just wanted to see if I
could observe the directional effects of my yagi.

Oddly, though, my Alinco DR-130 came with a CB MAGMOUNT when I bought
it as a kid used. It even survived my keying it attached to that
thing, and I don't think it has any protection against high SWRs. I've
always wondered how my radio survived that. Maybe it didn't... I'll
have to test it when my license comes. I only think it works now
because I tried it a while back on MURS frequencies with a radio shack
scanner.

On Jan 22, 9:05 am, "Jeff" wrote:
" I'm sure it's not much of a performer, nelson. If you're using speaker

wire as your feeder, it's going to be horribly mismatched. Your trx
expects to see 50 ohm on the antenna, and (though I'm not certain) I'd
be willing to bet that your speaker wire is either much higher or much
lower. At best, this will give terrible performance. At worst,
potentially blow up the output stage of your rig.
RG58 is the coax you need. It's cheap, sometimes free. It's the same
stuff old 10base2 networks used to be wired with, so a visit to a dump
will probably turn up loads.He did say he was using coax, the speaker wire was just a ground, which
won't really be doing very much at vhf, so that is not the problem.

73
Jeff