1. How To DIY A Shortened 20 thru 40 Meter Vertical For POTA (Як зробити своїми руками скорочений вертикал від 20 до 40 метрів для POTA) - https://mikestechblog.com/how-to-diy-a-shortened-20-thru-40-meter-vertical-for-pota/
2. Master Portable Operations: Reel POTA-ble Antenna Review (Огляд котушкової POTA-ble антени) - https://ke2yk.com/2024/07/11/master-portable-operations-reel-pota-ble-antenna-review/
3. CQ Magazine Archives Online (Архів журналу CQ) - https://hamcall.net/cgi-bin/cqcgi
** The DX Bulletin (TDXB) - https://archive.org/details/the-dx-bulletin
** Minnesota Amateur Radio Technical Society newsletter - https://archive.org/details/mn-arts
4. Antenna online calculator - https://3g-aerial.biz/en/s11-return-loss-vswr
5. Zero Retries Interesting Small Vendors Catalog (Цікавий каталог малих постачальників) - https://www.zeroretries.org/p/zero-retries-interesting-small-vendors
73 de UT2AB
