BD8ENX "斜杠" is pronounced "slash", and "portable" means a handheld radio, or "is/p".
Internationally, it is customary to write: call sign /p
Read as: call sign + portable
Internationally, it is customary to write: call sign /m
Read as: call sign + mobile
Internationally, it is customary to write: call sign /qrp, which should be read as: call sign + slash + qrp (or call sign + qrp)
Internationally, it is customary to write and pronounce: call sign /7 (instead of the more common domestic pronunciation of "portable seven").