Copasetic Flow

  I knew I saw a video with 9 volt batteries used for arc welding!  During the ongoing discussion about Agent Sonya , using 9 volt batteries as a vacuum tube plate current power supply came up. I found references to doing such a thing on one of Pete's blog post s. I also vaguely remembered a Jeri Ellsworth video where forty 9-volt batteries were connected in series. (The tops of these batteries makes the operation fascinatingly simple.) I finally found the video today. It is amazing! So! We now have visual evidence that nine volt cells can be put to rather spectacular use!

 I just saw a heartening post with respect to the gang's and my quest to see if Agent Sonya could have built her own radio rig. Pete, one of the presenters on Soldersmoke even mentions W1REX in the post in conjunctions with this transmitter schematic : Rex is better known in these parts as the ham that produces RockMite and Tuna Topper kits that populate the innards of Project TouCans. Getting back to Agent Sonya , and also to safety, I was heartened to see Pete mention a supply that had occurred to me for plate voltage and current: nine-volt transistor batteries. Gone forever, apparently, are the B cells of yore, but we can definitely string together 9 volt cells. I wandered if there were issues with this type of supply I'd missed. There aren't! The post and the circuit above also answered a question I'd often wondered about with respect to keying tube circuites. That MPSA92 looks pretty hefty what with its 300 volt rating. It is and it isn't. the maximum curren...

 One consideration that I hear often with relation to vacuum tube circuits is to be very, very careful of the high voltages that are typically involved. And, I completely agree. What if the highest voltage was 45 V though? A battery operated rig would seem more useful to Agent Sonya in my opinion. I went searching for something that might take less voltage, and therefore be safer for construction by the gang and I. It didn't take too long to find something that might work as a basic concept, although I do understand that the operating frequency of the circuits shown below wouldn't transmit long distances. Here are the schematics from the 5 meter rig outlined in the March, 1936 issue of Radio Craft  on page 525 Notice that at first glance, the highest voltage involved is from a 45 V battery. The 'interruption-frequency' coil concerns me a bit because I don't know what it's for yet, and it looks like a transformer. Upon further reading, and squinting at the acro...

 How difficult is it to build a single tube ham transmitter? Honestly, I don't know because I haven't tried. The gang and I are out camping this week and thoroughly enjoyed listening to the latest episode of the Soldersmoke podcast as we were out exploring the area around Baker, NV. In the podcast, (episode 260), Agent Sonya  came up again. (Here's the Soldersmoke blog post for the podcast.) I have to say, I'm still a believer. Maybe it's time to put my money where my mouth is though. So, this week, the kids and I will be researching: The article in the 1936 radio handbook on page 111. Whether or not we can still get our hands on a functioning 6C6 tube and socket. Can we find a crystal that fits into a socket like the ones advertised in the back of the handbook? Can we maybe bring the plate voltage 6A6—aka a 53 tube—down to something more manageable than 450 Volts?  How does the circuit function and how does it depend on plate voltage anyway? What sort of oscilla...