Как да разберем, че Соларният котлон е правилно фокусиран?

https://hosasolar.bg/%D0%B1%D0%BB%D0%BE%D0%B3/%D0%BA%D0%B0%D0%BA-%D1%80%D0%B0%D0%B7%D0%B1%D0%B5%D1%80%D0%B5%D0%BC-%D1%87%D0%B5-%D1%81%D0%BE%D0%BB%D0%B0%D1%80%D0%BD%D0%B8%D1%8F%D1%82-%D0%BA%D0%BE%D1%82%D0%BB%D0%BE%D0%BD-%D0%B5-%D0%BF%D1%80%D0%B0%D0%B2%D0%B8%D0%BB%D0%BD%D0%BE

posted from Bloggeroid