10/20/61 cable from JMWAVE to Director: "Lazaro present leader MRR. AMBRONC-5 will be national military coordinator upon return from (Cuba)...Lazaro arrested due Saborit who worked AMPUG net. AMPUG introduced Lazaro to Saborit at time MRR using PEKLOK channel. (This probable took place at time NOTLOX radio being transferred from Venezuelan embassy to a safehouse.)...C/S comment: Request Lazaro be completely debriefed re NOTLOX circuit."
A memo provided by CIA to HSCA staffers identified PEKLOK as a "communications circuit".