uhd_cal_rx_iq_balance: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/uhd_cal_rx_iq_balance - from package: uhd-host

You may install the required package with command apt-get install {package}

Error in other languages:
uhd_cal_rx_iq_balance: bevel nie gevind nie
uhd_cal_rx_iq_balance: comandă negăsită
uhd_cal_rx_iq_balance: comando não encontrado
uhd_cal_rx_iq_balance: commande introuvable
uhd_cal_rx_iq_balance: command not found
uhd_cal_rx_iq_balance: käsku ei ole
uhd_cal_rx_iq_balance: không tìm thấy lệnh
uhd_cal_rx_iq_balance: komanda nerasta
uhd_cal_rx_iq_balance: Kommando nicht gefunden.
uhd_cal_rx_iq_balance: kommandot finns inte
uhd_cal_rx_iq_balance: komut yok
uhd_cal_rx_iq_balance: nie znaleziono polecenia
uhd_cal_rx_iq_balance: níor aimsíodh an t-ordú
uhd_cal_rx_iq_balance: no se encontró la orden
uhd_cal_rx_iq_balance: no s'ha trobat l'ordre
uhd_cal_rx_iq_balance: opdracht niet gevonden
uhd_cal_rx_iq_balance: parancs nem található
uhd_cal_rx_iq_balance: perintah tidak ditemukan
uhd_cal_rx_iq_balance: príkaz nenájdený
uhd_cal_rx_iq_balance: příkaz nenalezen
uhd_cal_rx_iq_balance: команда не найдена
uhd_cal_rx_iq_balance: командата не е открита
uhd_cal_rx_iq_balance: 命令找不到
uhd_cal_rx_iq_balance: コマンドが見つかりません