AlphaFive
Member
I have been recently frustrated after moving my four discones around in my attic. I realized my Tram 1411, attached to a BCD536, had originally come with a long jointed top whip. I felt as though I was not utilizing the 1411 to it's fullest capacity.
1st problem, my attic mount height from floor base to top beam was only 5' 6". Far short of the discone with it's top whip. I researched for a period of time, I was able to piece together that if I wanted the best reception below 100 MHz. I needed to find a way to mount the top whip.
Well, I had been hanging the discone from the top beam with bailing twine, sans the top whip. I set down the discone into the recycled fiber insulation (which is supposed to be fiberglass free) . At that point height restriction only allowed the bottom half of the whip to fit into the top coil. Okay, lets try it. What occurred with the top whip on, and sitting in the fiber insulation was a degradation, in two places that should have not suffered. An A.T.I.S. at 120.200 had to have the squelch opened all the way to receive the voice modulation. A DMR frequency at 454 Mhz. suffered 1 to 2 bar loss if I parked my BCD536 on the freq.
I went back up in the 'crawlspace'.. took off the half whip, and rehung my 536. I was able to receive the A.T.I.S. at 120.200 on # 4 squelch with a decent voice modulation. My 454 Mhz. DMR went back up by 1 to 2 bars.
I cannot say what would have occurred if I had the ability to hang the discone insulation free, with a whip. But, I can say that without the whip, and hanging free, my V.H.F. above 100 and U.H.F. were improved. Don't know which was a deciding factor, insulation or the whip itself....odd
1st problem, my attic mount height from floor base to top beam was only 5' 6". Far short of the discone with it's top whip. I researched for a period of time, I was able to piece together that if I wanted the best reception below 100 MHz. I needed to find a way to mount the top whip.
Well, I had been hanging the discone from the top beam with bailing twine, sans the top whip. I set down the discone into the recycled fiber insulation (which is supposed to be fiberglass free) . At that point height restriction only allowed the bottom half of the whip to fit into the top coil. Okay, lets try it. What occurred with the top whip on, and sitting in the fiber insulation was a degradation, in two places that should have not suffered. An A.T.I.S. at 120.200 had to have the squelch opened all the way to receive the voice modulation. A DMR frequency at 454 Mhz. suffered 1 to 2 bar loss if I parked my BCD536 on the freq.
I went back up in the 'crawlspace'.. took off the half whip, and rehung my 536. I was able to receive the A.T.I.S. at 120.200 on # 4 squelch with a decent voice modulation. My 454 Mhz. DMR went back up by 1 to 2 bars.
I cannot say what would have occurred if I had the ability to hang the discone insulation free, with a whip. But, I can say that without the whip, and hanging free, my V.H.F. above 100 and U.H.F. were improved. Don't know which was a deciding factor, insulation or the whip itself....odd