Notes from day at Goldstone 5/11/00 obsevers: PG, KL, CN, DS * News: The bullgear work will not be done until mid-July. This means we will not take moon data during our upcoming 3-day pass. * Installed Sun monitor into the rack. (Sun video connector was damaged while monitor was on external table). * BHP-200 filters work fine, 3dB loss at 82 MHz. Visually appears to "turn on" around 50 MHz. No observed attenuation up to IF frequency of 320 MHz. They remove the ratty LF noise we observed last time * Checked out hardlines + other cables. Measured attenuation at 200MHz and 300 MHz. Used a loop of cables: RG/223 (30') + RG/214 (50') + hardline (493') + RG/214 (40') and back through identical cables. configuration A: RG/223 only configuration B: bypass hardlines: RG/223 and RG/214 only configuration C: all Peter has a plot, can be seen at internal/figures/hardline.eps on the webpage measured losses: (keep in mind this is twice what we would observe going one way) 200 MHz 300 MHz ------------------------------ A: 3.5 dB 4.6 dB B: 6.0 7.8 C: 14.5 17.3 RG-223: 0.058 dB/ft 0.077 dB/ft 1.32 RG-214: 0.025 dB/ft 0.032 dB/ft 1.28 hardline: 0.0086 dB/ft 0.0096 dB/ft 1.11 (Note, this corresponds very well to the specs I found subsequently: RG-223:0.06 RG-214:0.027 @200 MHz) So we can reduce our losses by at least a factor of two by using pure hardline. Of course this is not the whole story since we have not measured dispersion. Nothing was noticeable with a pulse containing up to 150 MHz. At least the hardline appears to have the smallest attenuation slope vs. frequency. * We attempted to setup the new trigger: S-RCP-14 * S-LCP-14 * S-RCP-13, with no L-band veto. We appear to have the hardware to do it. * We blew 2 of 3 diodes. This may be due to spike coming out of amplifiers when we turn them on. We need to rework the front end (UHE nu downcoverter) so that we can check the power we are putting into the diodes. Perhaps we will put spigots on the front to make this easier. Action items: ------------ * Reschedule our 3-day pass. Even if we cannot get 3 days, even one or two days would work since we want to test our new trigger configuration. * replace long runs of RG/223 and RG/223 with shorter hardline. also at far end * Someone wanted to show the plot/numbers to the radar group. * purchase: SR400. a printer with a serial port for Sun & oscilloscopes. new diodes + spares GPIB controllable attenuators cheap & simple scalers * Redesign UHE-nu downconverter so diodes can be connected only after checking the power levels. * Need to make a triggerable spark generator * We should request a locked cabinet for leaving RF hardware & assorted tools. * See if we can get software to read a partial record from Tek580. Next time: --------- * Need to test DSS-13 pulses with sparks. * Bring lemo/bnc adaptors so we can use other 222 gate generator * Bring more NIM coincidence units just in case.