= RF Oscillator for LCGT = <> == Applications == * RF signal source for phase & amplitude modulations of the laser for sideband generation. . For this purpose, the required frequency range is from 10MHz to 150MHz. We will first use variable signal generator to search for the best modulation frequency. Once the modulation frequencies are precisely decided, we will make crystal oscillators of those specific frequencies to achieve the ultimate low phase noise. * Phase lock of two lasers, particularly for the green lock. . This application requires a stable but variable sine wave source which can change the frequency from near DC up to 1GHz without phase discontinuity. * Both applications require very good phase noise at around 100Hz. The best available synthesized signal sources seem to reach less than -120dBc around 100Hz. Oscillator phase noise study [[attachment:osc15M_publish.pdf|report]] by Akutsu. == Variable Frequency Signal Generator == This signal generator has to be able to perform frequency modulation. FM is useful to optimize the sideband frequencies to, for example, maximize the MC transmission. We need several of those generators (order of 10). So the price cannot be too high. Some information on this kind of signal generators is available [[LCGT/subgroup/Electronics|here]]. === Rhode & Schwartz === ==== SMB100A ==== http://www.rohde-schwarz.co.jp/ja/products/test_and_measurement/signal_generation/SMB100A.html * 765,450JPY * 9kHz - 1.1GHz * -140dBc/Hz@100Hz for f = 10MHz * -120dBc/Hz@100Hz for f = 100MHz * -141dBc/Hz@20kHz for f = 100MHz * FM OK * GPIB, LAN, USB ==== SMA100A B103 B22 ==== http://www.rohde-schwarz.co.jp/ja/products/test_and_measurement/signal_generation/SMA100A.html * 2,577,960JPY * 9kHz - 3GHz * -151dBc/Hz@20kHz for f = 100MHz * No phase discontinuity * FM OK * GPIB, LAN, USB === NDK === ==== SG010M3R0GB ==== http://www.ndk.com/jp/products/search/sg/SG010M3R0GB.html * 735,000JPY * 10MHz - 3GHz * -130dBc/Hz@100Hz for f = 10MHz * -120dBc/Hz@100Hz for f = 50MHz * -130dBc/Hz@20kHz for f = 50MHz [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/LCGT/subgroup/Electronics?action=AttachFile&do=view&target=SG010M3R0GB_test_sheet.pdf|Test sheet]] == Crystal Oscillator == === Wenzel === http://www.wenzel.com/