Discussion in 'Amplitude Modulation' started by AC0OB, Oct 15, 2019.
If I ever hear you on, I will give you a shout!
I'm on 160 m. now mostly. I've found lately that 75 m. sucks for my kind of operating: armchair copy ragchews. I hear guys on 75 at night, but they're distant and wafting in and out with QSB. I can copy one or two okay but they're always working guys who have signals that are mixed in with noise. In the daytime the locals are absorbed into the ionosphere and at night they skip right over me. 160 is no picnic because so many hams have poor antennas but at least I have a chance of raising guys within 100 miles or so and working them reliably.
Things are often solid on 80 meters at night on the East coast.
Solid copy from NJ to GA both ways on this rig, but close in might not be as good.
Georga and North Carolina often come in strong, along with Western PA and Ohio.
I had a number of solid qso's last night running 25 watts carrier out of the flex 5000.
I try and not make long transmissions on lower power even if the copy is good at the far end because people in other
locations my not hear me at all.
I would have to get radical to get on 160. I just don't have much space for an antenna that would work very well.
I could do something but it would hose up my current 80 and 40 setups.
You should contact Rob and ask him how he does his. Rob lives on a postage-stamp size city lot near Chicago and still manages to put a decent signal into here on 160, and is strong on 75m as well.
I worked Dr John in Florence AL last night on 1885 kc/s. Tried both the vertical tee and the 80m dipole. The dipole was a bit better on transmit, but a lot better on receive. I used the indoor loop for receive whilst transmitting on the vertical, but it still wasn't as good as the dipole. As the crow flies, John is about 130-150 miles from here.
We ended the QSO just as atmospheric noise was steadily building and readability was becoming marginal. I thought it sounded a lot like tornado static even though the wx was clear here. This morning I heard about the tornado that hit Dallas last evening.
To know if it is full transmit check the junction of R9 and the drain of Q8. In transmit it should be close to ground.
Also look at "MOD," (top of C24 or R15). Without modulation in transmit it should be at +12V, with modulation it should kick up towards +24V.
Q8 checked ok, I just ordered another kit and will see how that goes.
Reworking the board is not easy with some parts...
Yes, Clark told me how you can turn any dipole into a 160 meter antenna.
But that would disrupt 80 meter operation.
In my setup it would not be easy to switch between configurations.
At some distances my 80m dipole (average height 110') puts in a better signal than does the quarter-wave vertical tee. I have to go down to the tower and turn a switch and then, back in the shack re-set the remote tuning adjustment to change over. Takes about 5 minutes, so I can't do a "wire array vs 160m dipole" type of test.
Speaking of the tower, I completed the 90' level guy wire replacement last week. Plan to do the 60' next spring when wx warms up. Probably won't do anything at the 30' level any time soon since they still appear to be in good shape. Did the 120' level two years ago.
Thanks Don; from my experience a separate rx antenna is mandatory. Fellows who transmit with good rx antennas are almost always using bad tx antennas. A few years ago I was starting to wonder if the effort for 160 was worth it. I remember some Heavy Metal Rallies where I called CQ forever on 1880 and all the action was on 75. Now I'm glad to have 160 available to me.
Congratulations Don; I think the top two levels are the most important. And as you go down in height, the length of the guys is less.
I did find one cracked insulator on one of the old guys. It hadn't fallen apart and the part between the two loops of cable that take the compression was still there, so no harm done. There was some rusty deposit of the ceramic at the crack, indicating it wasn't fresh but had been there for a long time. A few years ago I had one insulator to fail in the bottom set. I just left it alone for a couple of years before fixing it, but it was easy to replace. It would suck to have to go all the way up, take one top guys down and fix it, just because of one insulator. It would take 3 round trips up the tower to attach a temporary guy, fix the old one and re-attach it, and then remove the temporary one.
I think my 30-minute brisk walk every evening is what has conditioned me to be able to do the climbing.