Copasetic Flow

 TouCans is back up and running! The battery noise is also just gone! One issue caused both the noise and the key stoppage. The ground wire connection from the keyer relay was in the process of breaking away during the fixes last week. This led to the noise I heard in the rig. It also led to the wire, of course, actually detaching which kept the keyer from working. KO6BTY soldered the ground connection back this morning, and TouCans is back up and running well! Here's what the noise before the fix. This is what a wire breaking in TouCans does. The new battery is doing a good job. Here's how the RBN saw TouCans right after the fix.

 I had an interesting failure with TouCans a day ago. TouCans handily activated a park a day last week. Then, yesterday, when I pulled on the antenna wire just a bit, (I promise), the RockMite keyer rebooted which is never a good sign. I adjusted the wire again and the rig audio went off. What had actually happened was that the power supply had shut itself down. I inspected the interior of TouCans and immediately wondered if the power leads to the Tuna Topper ][+ amplifier had shorted on the tuna can. I unhooked the power lines to the amplifier and tried again nothing. Leaving the power lines detached, I decided to check if the power supply would take a charge. It would. I tried again and the RockMite, (as evidenced by its keyer), booted!  I left everything for a bit before, this morning reassembling the rig with the power lines to the amp re-attached along with the RF output line that I had accidentally broken in the process. I checked the bias voltage to the power transisto...

 Project TouCans is back up and running! The rig just stopped dead in its tracks during the NAQCC Sprint a few weeks back, and that was that. After two hours of debug and soldering yesterday, it's back. A few things of note: The battere was completely dead. The imuto power supplies TouCans uses hold their charge for weeks, so I'm guessing this was the number one issue. But! The battery didn't do it's usual buck supply hum into the radio, (hence me not realizing it was even close to being out of juice.)  The lack of buck supply hum might have been precipitated by the second issue I found. The audio output wire was severed within its insulation. A DC ohmmeter check indicate that there was an open circuit. I'm wondering though, if the wires were close enough together in the insulation if they weren't capactatively coupled, and therefore still producing sound and providing a bit of a filter. I replaced the wire in question, so we may never know. Here are the spots...

 I finally landed at a quiet tape vs. noise  configuration for TouCans on Saturday afternoon. Here’s how. In the picture above, the wires circled in green include the + and - power wire, (white and red respectively), and the keyer wire, (also red.) When I taped the bundle of wires including the single turn coil shown in the white wire to the side of the can, the noise from the power supply went away. I was left with only noise from the radio, (the kind I want), and a gentle hum from the power supply because it had switched into buck converter mode to step its voltage up to the required 15V! The helicoptering from the Pico-W was also almost gone. In other parts of the project, the Pico-W has started burning through pairs of AA batteries rather quickly.

 Here's the query I'm using for Burr Trail ============================================ select   tx_lng,   tx_lat,   rx_lng,   rx_lat,   rm_rnb_history_pres.timestamp,   rm_rnb_history_pres.dB,   rm_rnb_history_pres.Spotter,   haversine(tx_lat, tx_lng, rx_lat, rx_lng) as total_path,   gis_partial_path_lat(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lat,   gis_partial_path_lng(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lng,   id,   strftime('%Y%m%d', timestamp) as date,   strftime('%H%M', timestamp) as time,   'US-4399' as park,   'KD0FNR' as call,   1770.829467773438 as elev_tx from   rm_rnb_history_pres where   dB > 100   and timestamp > '2024-05-27'   and timestamp < '2024-05-28' order by   rm_rnb_history_pres.timestamp desc ======================================================= At some point I'll add an ionosonde field using this map for each QSO. For the Boulder, CO...

Summary:  Classes started this week.  They're a lot of fun, but they take time.  Consequently, the lab work is moving a little more slowly.  I'm looking into what we can accomplish with a YBCO superconductor sample.  The advantage is that we can test our experimental techniques using relatively cheap liquid nitroogen intead of iquid helium.  The downside is that with the size of YBCO sample we have, the expected maximum energy is only 3 deV which is kind of low without a specialized detector. For more background on the experiment, please scroll to the bottom of the post. The percolator peak does not appear when the detector is initially turned on.  The attenuator does however appear to create a rather copious amount of noise. Suppose we used YBCO as a sample.  The energy we could expect doing a back of the napkin calculation is 3.8 keV.  The flux is approximately 230 photons for our sample size.  For a 25 square mm detector t...

Summary :  Initial results from the Dewar attenuation tests look odd.  They won’t be conclusively odd until all the sources have been measured for the same counting time.  At the moment, the Cs 137 32 keV line is less attenuated than the 22 keV Cd 109 line which is expected, but it also appears to be less attenuated than the Cd 109 88 keV line which is not expected.  It seems like a higher energy should have an easier time getting through the Dewar material. To Do Today: .        Calculate the count rate from the Cs 137 source and compare it to the expected flux from Hirsch’s theory .        Run a simulation on a much smaller diameter coil looking into quenching the small YBCO superconductor. .        Analyze the overnight run on Cs 137 Bias 1500 V Gate Window 0.5 uS Threshold 1.5mV Attenuatio...

Lab Book 2014_08_14     Hamilton Carter Summary:   Took several more spectra trying to characterize the behavior of the detector. New to the experiment?  Scroll to the bottom for background. Low Gain linearity run Bias 1100 V Gate Wind0ow 0.5 uS Threshold 1.5mV Attenuation 6 dB Data set HBC_0005 Source Cs 137 taped to window Start Time 8:58 AM Stop Time 11:02 AM Date 2014_08_14 x-y scope V/div 1, 0.5 Shielded? Yes Tube Harshaw B- The source is taped directcly to the window of the detector.  This will give the maximum number of particles from the source impacting the detector.  The counts from these runs will be used to determine the number of counts per second from the source. Picture of the...