MacKenzie claims that the tests, which will not take place until July next year, should happen sooner.
"This is a snow job and yet another example of Rajar doing what it has done for the past three years - finding any excuse to delay the inevitable and kick the whole issue of the introduction of electronic measurement of radio audiences into the long grass," MacKenzie said.
"There is no need whatsoever for Rajar to have to wait another year for testing the second generation of meters. GfK Media (which runs an electronic audit for MacKenzie) has carried out a national survey since March with stable, accurate results published monthly since then and today it is publishing the results of London commercial stations."
However, Rajar, reacting to mounting pressure over its decision to reject electronic measurement last July in favour of its current diary-based system, said that there were good reasons why the tests couldn't take place immediately.
Jane O'Hara, the managing director of Rajar, said: "I am pleased to announce that both Arbitron and Radiocontrol are developing exciting next-generation technology, which we hope will prove to be more suitable for the UK market. We are keen to begin tests with both of them. However, disappointingly but understandably, neither company can deliver test equipment to us until July 2004."
MacKenzie, who has adopted the Radiocontrol wristwatch system to measure audiences, has threatened Rajar with legal action, claiming that its methods were underestimating his audience and costing him ad revenue.