This is not to admit that the problem of RF1 is insuperable in the case of the SPS. There are over 50,000,000 consumer microwave ovens in existence today in the world. In addition, thousands of multi-kilowatt ISM heating sources have been in existence for years at induction frequencies (< 500 MHz), RF bands (principally 27 MHz) as well as at microwave frequencies (0.915, 2.45 GHz). Despite this, studies (14) have shown that they cause minimal complaints of interference. The data in Table 6 show that generally less than 5% of all interference complaints are due to ISM. (The exception in Finland is not understood.) In addition, there is hope that efficient microwave tubes for the SPS can be made with lowered noise. In Fig. 2, we show microwave spectra of older noisy cooker tubes and newer tubes (15) operated under carefully temperature limited, but stable conditions. The reduction in noise in this tube work by W. C. Brown is exceptional and an encouraging sign for the resolution of RFI problems in the SPS. Even if all SPS tube noise is eliminated, we must still contend with the problem of potential incidental interference — i.e., the possibility of safe environmental levels of 2.45 GHz microwaves energy causing interference with or even damage to consumers or commercial electronic devices like computers. In Table 7, we compare the RF
RkJQdWJsaXNoZXIy MTU5NjU0Mg==