JI1FGX/DU9　ミンダナオ日記

24MHzダイポールを追加しました　(2024/10/13) Installed a 24MHz Dipole Antenna (October 13, 2024)
「24/10/12 24MHzのアンテナ制作」で作ったアンテナを実際にタワーに取り付けてSWRを調整していました。Ｆａｎ out型というそうです既存の18MHzのエレメントに24MHzを同じ給電点に追加したFan out型アンテナです I was adjusting the SWR after installing the antenna made on October 12, 2024, as described in this link. It is a Fan-out type antenna. The 24MHz element was added to the same feed point as the existing 18MHz element, forming a Fan-out type antenna.
MMANAを使わずにNanoVNAだけでぶっつけ本番の調整を行いました。最初に２４MHｚのエレメント長と角度の調整計算上では300/24.915/40.95=2m86mになるはずなのですが、実際にNanoVNAで測定しながら長さ調整をすると2m53cmになりました。エレメントは2mはなしてあります次に18MHzのエレメント長微調整 300/18.100/40.95=3m94cmになるはずなのですが、エレメントの実測値は3m70cmでした。ちなみにタワーの高さは21m 50MHzと７,21MHｚダイポールが18m 18MHzのダイポールは12m 24MHzのダイポールが10.5m のところに取り付けてあります I performed the tuning on the spot using only the NanoVNA, without using MMANA. First, I adjusted the element length and angle for 24MHz. According to the calculation, it should be *300/24.915/40.95 = 2m86cm. However, when I actually measured with the NanoVNA and adjusted the length, it turned out to be 2m53cm. The elements are spaced 2m apart. Next, I made fine adjustments to the 18MHz element length. The calculation was 300/18.100/40.95 = 3m94cm, but the actual measurement was 3m70cm. By the way, the tower height is 21m. The 50MHz and 7/21MHz dipoles are mounted at 18m, The 18MHz dipole is at 12m, And the 24MHz dipole is at 10.5m*.
NanoVNAで測定した結果１８MHｚと２４ＭＨｚの二つのバンドにＳＷＲの最低値が有ります According to the measurements with the NanoVNA, There are minimum SWR values for both the 18MHz and 24MHz bands.
NanoVNAで測定してみると18.160MHzにSWR最小値が有り1.36ですバンド内ほぼフラットです After measuring with the NanoVNA, I found the minimum SWR at 18.160MHz, which is 1.36. The SWR is almost flat across the band.
NanoVNAで測定してみると24.890MHzにSWR最小値が有り1.16ですこちらもバンド内ほぼフラットです After measuring with the NanoVNA, I found the minimum SWR at 24.890MHz, which is 1.16. The SWR is almost flat across the band as well.
南国のフィリピン、それもミンダナオ島は最南端に位置していて北緯８度です。朝６時から５０MHzのアンテナ修理と18，２４MHzアンテナの調整作業を始めて午後２時までかかりました。太陽は真上からジリジリと照り付け肌が痛くなります。エレメントを調整してはエアコンが聞いたシャックに戻りNanoVNAの値の確認、また外で作業途中で何度も水を飲みましたが頭がくらくらしてきました。昼ご飯を食べて休憩せずにすぐに残りの作業。全てが終わったのが14時でした。そしてすぐにセブンイレブンへ行ってポカリスエットを買ってきました。２Lのポカリスエットが165ペソ　445円です。 In the tropical Philippines, specifically in Mindanao at the southernmost point, located at 8 degrees north latitude, I started antenna work at 6 a.m. The task included repairing the 50MHz antenna and adjusting the 18MHz and 24MHz antennas, which took until 2 p.m. The sun was beating down directly overhead, causing my skin to burn. I would adjust the elements, then go back to the air-conditioned shack to check the NanoVNA readings, and then back outside to continue working. I drank water several times, but I started feeling lightheaded. After lunch, I didn’t take a break and immediately continued with the remaining work. I finished everything by 2 p.m. and then went to the 7-Eleven to buy a 2L bottle of Pocari Sweat for 165 pesos (about 1.75 USD).

2024年10月13日　 2024年10月14日
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24MHzダイポールを追加しました　(2024/10/13) Installed a 24MHz Dipole Antenna (October 13, 2024)
「24/10/12 24MHzのアンテナ制作」で作ったアンテナを実際にタワーに取り付けてSWRを調整していました。Ｆａｎ out型というそうです既存の18MHzのエレメントに24MHzを同じ給電点に追加したFan out型アンテナです I was adjusting the SWR after installing the antenna made on October 12, 2024, as described in this link. It is a Fan-out type antenna. The 24MHz element was added to the same feed point as the existing 18MHz element, forming a Fan-out type antenna.
MMANAを使わずにNanoVNAだけでぶっつけ本番の調整を行いました。最初に２４MHｚのエレメント長と角度の調整計算上では300/24.915/40.95=2m86mになるはずなのですが、実際にNanoVNAで測定しながら長さ調整をすると2m53cmになりました。エレメントは2mはなしてあります次に18MHzのエレメント長微調整 300/18.100/40.95=3m94cmになるはずなのですが、エレメントの実測値は3m70cmでした。ちなみにタワーの高さは21m 50MHzと７,21MHｚダイポールが18m 18MHzのダイポールは12m 24MHzのダイポールが10.5m のところに取り付けてあります I performed the tuning on the spot using only the NanoVNA, without using MMANA. First, I adjusted the element length and angle for 24MHz. According to the calculation, it should be *300/24.915/40.95 = 2m86cm. However, when I actually measured with the NanoVNA and adjusted the length, it turned out to be 2m53cm. The elements are spaced 2m apart. Next, I made fine adjustments to the 18MHz element length. The calculation was 300/18.100/40.95 = 3m94cm, but the actual measurement was 3m70cm. By the way, the tower height is 21m. The 50MHz and 7/21MHz dipoles are mounted at 18m, The 18MHz dipole is at 12m, And the 24MHz dipole is at 10.5m*.
NanoVNAで測定した結果１８MHｚと２４ＭＨｚの二つのバンドにＳＷＲの最低値が有ります According to the measurements with the NanoVNA, There are minimum SWR values for both the 18MHz and 24MHz bands.
NanoVNAで測定してみると18.160MHzにSWR最小値が有り1.36ですバンド内ほぼフラットです After measuring with the NanoVNA, I found the minimum SWR at 18.160MHz, which is 1.36. The SWR is almost flat across the band.
NanoVNAで測定してみると24.890MHzにSWR最小値が有り1.16ですこちらもバンド内ほぼフラットです After measuring with the NanoVNA, I found the minimum SWR at 24.890MHz, which is 1.16. The SWR is almost flat across the band as well.
南国のフィリピン、それもミンダナオ島は最南端に位置していて北緯８度です。朝６時から５０MHzのアンテナ修理と18，２４MHzアンテナの調整作業を始めて午後２時までかかりました。太陽は真上からジリジリと照り付け肌が痛くなります。エレメントを調整してはエアコンが聞いたシャックに戻りNanoVNAの値の確認、また外で作業途中で何度も水を飲みましたが頭がくらくらしてきました。昼ご飯を食べて休憩せずにすぐに残りの作業。全てが終わったのが14時でした。そしてすぐにセブンイレブンへ行ってポカリスエットを買ってきました。２Lのポカリスエットが165ペソ　445円です。 In the tropical Philippines, specifically in Mindanao at the southernmost point, located at 8 degrees north latitude, I started antenna work at 6 a.m. The task included repairing the 50MHz antenna and adjusting the 18MHz and 24MHz antennas, which took until 2 p.m. The sun was beating down directly overhead, causing my skin to burn. I would adjust the elements, then go back to the air-conditioned shack to check the NanoVNA readings, and then back outside to continue working. I drank water several times, but I started feeling lightheaded. After lunch, I didn’t take a break and immediately continued with the remaining work. I finished everything by 2 p.m. and then went to the 7-Eleven to buy a 2L bottle of Pocari Sweat for 165 pesos (about 1.75 USD).