The Media Workers Association of SA (Mwasa) earlier said it expected all of its 600 workers to take part, while the Communication Workers' Union (CWU) said around 1000 of its members would participate.
The SABC has just over 3000 staff members.
The unions went to the Commission for Conciliation Mediation and Arbitration when the SABC revised a 12.2 percent multi-term pay offer it was supposed to have implemented in April, to 8.5 percent.
The Labour Court in Johannesburg dismissed a bid by the SABC last week to stop its workers from striking.
The protesters are expected to picket around lunch time, will not work overtime and will only do the duties in their job descriptions.
If there is no progress in negotiations with the employer, a complete
stay away will start on 13 July, unions warned.
Sapa

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