Toroids for transistor outputs will be powered through a relay controlled by presence of voltage on LED in cathode of one of 6P15P tubes. Also, there will be a couple of relays that protect speakers from DC. Protection circuitry, servo opamps, and power switch relay will be powered from a separate small power supply.
I am thinking about PCB for DIY community currently. Let's discuss details.
I think I will use Neutrik PC mount XLR inputs, Lundahl, or Jensen, or Altran input transformers (10K:10K), with pads to mount all of them when desired;
Russian military ceramic tube sockets, Russian military non-inductive metal-film resistors, metal-film capacitors, and high precision Vishay or Dale resistors for feedback loops. Some heatsinks will be needed as well: for gyrators of output tubes, for filament DC regulator, for B+ DC regulator. However, it may be a single wide heatsink for everything.
PS PCB will be a separate one, or is it better to put PS parts on the same PCB, except power transformer?
Power transformer and a reactor choke will be chosen from standard Edcor series.
By the way, speaking of Edcor. The last time I ordered them from Edcor, they were better than I expected, performed nice (too nice on lows, so some ringing on highs required extra efforts to buckle them up). Also, I still keep 3 transformers ordered by Cobra2, because he paid enough to ship 2 transformers, but not enough to ship the 3'rd one. Arny, please respond with your decision: to ship you output transformers, or to wait for enough money to ship all 3 of them, including power one.
I am open for an input. Please give me your suggestions.
This PCB will be reused in multiple projects I am going to present, one-by-one. The first one, however, will be an ultimate high end class A room heater.
I think I will use Neutrik PC mount XLR inputs, Lundahl, or Jensen, or Altran input transformers (10K:10K), with pads to mount all of them when desired;
Russian military ceramic tube sockets, Russian military non-inductive metal-film resistors, metal-film capacitors, and high precision Vishay or Dale resistors for feedback loops. Some heatsinks will be needed as well: for gyrators of output tubes, for filament DC regulator, for B+ DC regulator. However, it may be a single wide heatsink for everything.
PS PCB will be a separate one, or is it better to put PS parts on the same PCB, except power transformer?
Power transformer and a reactor choke will be chosen from standard Edcor series.
By the way, speaking of Edcor. The last time I ordered them from Edcor, they were better than I expected, performed nice (too nice on lows, so some ringing on highs required extra efforts to buckle them up). Also, I still keep 3 transformers ordered by Cobra2, because he paid enough to ship 2 transformers, but not enough to ship the 3'rd one. Arny, please respond with your decision: to ship you output transformers, or to wait for enough money to ship all 3 of them, including power one.
I am open for an input. Please give me your suggestions.
This PCB will be reused in multiple projects I am going to present, one-by-one. The first one, however, will be an ultimate high end class A room heater.
Wavebourn said:I have a pair of Russian 220V soldering irons for such purposes: 100W and 150W. I tried to bring 2 more from Russia, but they were confiscated in Dallas airport, because could be used as weapons be I a terrorist: they have wooden handles and sharp copper tips.
......and I thought that you made it yourself!
What you are doing in this thread is one of the best examples possible of what I think this forum is, or should be, all about. You are to be admired.
brianco said:
......and I thought that you made it yourself!
What you are doing in this thread is one of the best examples possible of what I think this forum is, or should be, all about. You are to be admired.
Thank you!
Currently, I show how I build prototypes, like breadboards that may be used on real field tests. They are suboptimal for manufacturing, of course, but convenient to test and tweak. After building a prototype I am going to design the same, but for production. However, a lot will look different, depending on test results, and chosen technology of manufacturing.
Wavebourn said:
Sorry, it was an attempt at humor... Those are very good capacitors.
I have purchased a lot of new surplus KMH capacitors at Halted (Kifer and
Lawrence Expy in Sunnyvale) for very good prices. If I use an electrolytic
it's usually a KMH for power supplies or a Sprague Atom for cathode
bypass, etc. in guitar amps
Thanks for the show ;-)
Michael
PS Halted sometimes have Rubycon also
PPS I have found sometimes new KMH need to be formed