1,385. Blowing Trumpets in Prayers for Fasts

Hilchos Taaniyos 4:16

The same is true in the second bracha, which is the first of the six that were added: the shaliach tzibbur would conclude the bracha, “Blessed are You, Hashem our God, God of Israel, for all eternity. Blessed are You, Hashem, Who remembers the forgotten." The people replied, “Blessed be the Name of He Whose glorious kingdom is forever and ever.” The gabbai would tell those who would blow the trumpets, “Blow a teruah, sons of Aaron, blow a teruah.” The one leading the service would then repeat, “May the One Who answered Moshe and our ancestors at the Red Sea answer you and hear the sound of your cry on today.” The kohanim would then blow a series of teruos, a tekiah and another series of teruos.

Hilchos Taaniyos 4:17

For each of the added brachos, he would alternate between, “Blow a tekiah” and “Blow a teruah,” until all seven blessings were finished. Therefore, sometimes the kohanim would blow “tekiah, teruah, tekiah” and sometimes they would blow “teruah, tekiah, teruah.” Seven sets of trumpet blasts would be blown. This was the order followed exclusively on the Temple Mount. When blowing tekios and teruos there, both trumpets and shofar would be blown, as has been discussed (in halacha 1:4).