Well I need a straight answer on something and I’m hoping to get some folks feed back. I have a pair of Coleman Raw DC board - can I supply them both from a single transformer? Maybe this has been explained but I can’t find it so…..thanks for any feedback!
If the transformer has two exactly separated secondary, it would working.
Two single transformer would be better, but this solution may work also.
Two single transformer would be better, but this solution may work also.
Best to post the schematic that you will use. The boards may not be compatible with it.
Thank you folks you’ve answered my question! I happen to have a suitable toroid with dual like secondaries.
I have asked of Rod my limit of amateur (stupid) questions for awhile. I wasn’t understanding how the filament of the 4P1L should be wired and I sounded like a dope. I just don’t want to be a pain-reserve those questions for serious issues.
I have asked of Rod my limit of amateur (stupid) questions for awhile. I wasn’t understanding how the filament of the 4P1L should be wired and I sounded like a dope. I just don’t want to be a pain-reserve those questions for serious issues.
I did follow up with him and he steered me in the right direction-while separate windings on the same transformer might be acceptable separate transformers are better. I managed to destroy my v9 regulators by shorting them to the chassis- i left the leads long and while manipulating the wiring I shorted the mosfet out. Rod gave me a whole procedure to go through to troubleshoot. He has been great. Also to be completely honest some of my reluctance in asking for help is fueled by vanity, pride and embarrassment. I’m Working through my flaws
A 3B7 is a dual triode DHT tube. The filaments can be wired parallel or series from the same source.
Why can’t 2 separate DHT tubes have their filaments wired the same as the 3B7 is wired internally from one source?
Why can’t 2 separate DHT tubes have their filaments wired the same as the 3B7 is wired internally from one source?
A 3B7 I read was for us use as an RF amplifier in Class C operation. I’m not sure I understand how class C works but the explanation I saw made me think that with the 3b7 one triode might conduct on th positive cycle of the input signal and the other in the bottom so the two triodes would not be conducting completely at the exact same time.
As far as audio is concerned: If you attempted to us it as an input tube for stereo the left and right channels would mix. If the two triodes were paralleled for one channel it would work fine. I believe it could work as a phase splitter too(LTP) and perhaps a differential amplifier.
My question originally was if I could use two separate winding from the same Antek 9v toroid to heat two 4P1L tubes for a linestage. The answer there was a probably/ maybe. There would be some artifact of each channel super imposed on that other that would likely be inaudible but possibly detectable with a scope. There is no possible way though to use a single winding to heat two DHT’s of opposing channels or stages with a single transformer winding because with DHT’s the cathode is the filament and the audio signal therefore is also traveling through the transformer winding.
I ultimately opted to buy two smaller 9v transformers because of the investment I made already in boards and parts. Why skimp when I’m trying to build the best version of the amplifier I can. Any way 3B7 seems like an interesting tube. I hope my answer makes sense and I certainly welcome any criticism as I am no expert but a total enthusiast!
As far as audio is concerned: If you attempted to us it as an input tube for stereo the left and right channels would mix. If the two triodes were paralleled for one channel it would work fine. I believe it could work as a phase splitter too(LTP) and perhaps a differential amplifier.
My question originally was if I could use two separate winding from the same Antek 9v toroid to heat two 4P1L tubes for a linestage. The answer there was a probably/ maybe. There would be some artifact of each channel super imposed on that other that would likely be inaudible but possibly detectable with a scope. There is no possible way though to use a single winding to heat two DHT’s of opposing channels or stages with a single transformer winding because with DHT’s the cathode is the filament and the audio signal therefore is also traveling through the transformer winding.
I ultimately opted to buy two smaller 9v transformers because of the investment I made already in boards and parts. Why skimp when I’m trying to build the best version of the amplifier I can. Any way 3B7 seems like an interesting tube. I hope my answer makes sense and I certainly welcome any criticism as I am no expert but a total enthusiast!
My amp is a stereo 2A3 SET with one power transformer. The 3B7 is the driver tube for both right and left channels. With the help of the tech that built the amp, we converted it to filament bias to heat the filaments (I’m not a tech or designer…just build kits and follow directions). The filament supply is a AC-DC meanwell module working off a 12VAC winding from the power transformer. The filaments are wired parallel with the ground going through a resistor.
The sound is definitely stereo with a wide, deep sound stage and very detailed. I have 6n1p/300b monoblocks and 5670/2A3 monoblocks, but I listen to this amp because it sounds better.
My question is why does this amp work heating two filaments with one source with this tube, but heating two filaments of two separate tubes with one source doesn’t work?
Musicalorgy, thanks for your informative response. My question isn’t directed specifically to you…just trying to learn something. Thanks
The sound is definitely stereo with a wide, deep sound stage and very detailed. I have 6n1p/300b monoblocks and 5670/2A3 monoblocks, but I listen to this amp because it sounds better.
My question is why does this amp work heating two filaments with one source with this tube, but heating two filaments of two separate tubes with one source doesn’t work?
Musicalorgy, thanks for your informative response. My question isn’t directed specifically to you…just trying to learn something. Thanks