NO !!! no power transformer!! it's dangerous when you're a beginner
Good suggestions. You get plenty of bang for your buck with all the hardware ready to rumble, and they could be passed on for the same or more if you get them working nicely.
Only consideration is that both need a protective base plate for safety.
Ami Rowe ex jukebox amps are also great starting points.
Only consideration is that both need a protective base plate for safety.
Ami Rowe ex jukebox amps are also great starting points.
I looked but there is only a really ugly wreck and then it risks getting lost in the wiring between the inhibition/mute circuit, the opts circuit etc etc etc.
it's still my favorite with magnavox consoles (which I can't find in europe to avoid the exorbitant shipping costs from the usa).
Okay. What method did you use? Does it have a name or can you describe how to do it for a problem where there is more than one loop?
Also, if you do understand Kirchhoff's Laws for DC circuits, then the next step would be doing it for AC circuits. In that case its similar to DC except complex numbers are required (j is the square root of -1, remember?), and we are not limited to resistors as the only passive components. Here is a link: https://people.clarkson.edu/~jsvoboda/Syllabi/ES250/ckts/KandOLaws_foc_ac.pdf
In the first schematic you posted, the DC test point is labeled 300V DC. The next power supply node the right will be a little lower voltage. The tube V2 will be biased to some quiescent current and so there will be some voltage drop across the resistance of the transformer primary winding. From the quiescent operating point the tube could conduct more current or less current, but that will be an AC variation in the tube current which represents an audio signal. At those frequencies the tube will be coupled by the transformer to the speaker load. The change in voltage across the transformer primary will be due to the load's reflected impedance at that frequency. Beyond that if the amplifier is biased for class AB operation then the tube will shut off during negative portions of the AC audio waveform. The other tube V3 would take over supplying current to the load. The transformer primary also forms an autotransformer which will couple the AC voltage at V3 back to the plate of V2, and vice versa. Therefore the plate/anode of V2 may rise to above the 300V DC or so that the power supply produces. Also, if you forget to hook up a speaker then the output transformer may be destroyed by internal arcing from very high induced voltages inside of the transformer.
Other than the above type of considerations, when you specify AC voltages you need to be clear about how you are measuring the voltage: peak, peak to peak, average, RMS, or whatever.
My first thought was this is way too high of a price, could ship @OldHector 's offer easily under half that. Then looked into it and it's a good amplifier, the only thing is remind me about my brother trowing out Oma and Opa's Magnavox, had the same amplifier. Guess let the auction run out and see if take half.
Thanks for confirming.
Good point about ready to go.
I am inept when comes to selling stuff, never get bites despite way underpriced compared to the market. So buying one already made mean stuck with it.
Richard (@OldHector ) the other issue is per what Mark said about each amplifier requires speaker wires specified by there manufacture, can't find this specification, therefore, with no speaker wires, can't use. Still puzzles me how manufacture's can get away with not specifying it since be responsible for the incorrect speaker wire being used.
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So the feedback loop is both AC and DC?
I am not going to deep dive into amplifier designing, just going to build an amplifier which has the correct components specified. Designing one seems far worse selecting a schematic that has only been built a few times, or once.
There is this interesting statement from Blueglow Electronics:
Based on what you said previously, they are opening themselves up to liability (someone builds an amplifier, like a Dynaco ST-70, and doesn't do the required checking of every component, and damages their speaker wire.
So the statement every single schematic has to have every component and circuit evaluated doesn't make since, especially as the Dynaco ST-35 was recommended to me.
Speaking of which, turns out the ECF80 can be used instead of the 7199 solving that hangup of mine. Now if OPTs could be found for it...
I didn't ask for a thesis, just a value to demonstrate understanding. 😛
Here's the file at Microsoft.
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170
You're still not paying very good attention. No wonder you have trouble with communication. Didn't you notice the warning? If you did, didn't it occur to you to ask about how to avoid what for you might be catastrophic loss of your amplifier by a momentary lapse (and we have already talked about the dangers of momentary lapses)?
You also didn't ask about how to make Kirchhoff's laws for AC circuits easier to deal with, nor does it appear to did a google search to help you find out. Not very motivated to learn about audio, yet wanting to jump right into high voltage projects?
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Thank you! 😀
Darn Microsoft never does make it easy, first couldn't find that, then instal, wait the 15 minutes for it to re-start, then get the same error message.
It takes a lot for someone to start irritating me, feel like getting close, for your information.
Okay, since you have now told me the feedback loop is AC and DC, plus a previous statement need to learn Kirchhoff's laws so every component of every amplifier can be checked, especially the feedback loop, then yes, I am ready to learn from you (already reading the book, great information on layout, part of which done to avoid shock).
As for Google search, I been fighting a Microsoft OS instead of waiting to get a ride over to the storage unit and getting my XP machine. If you want me sooner, can PM my cellular number.
You don't have to be interested in amplifier stuff. Maybe you are you still interested in solving your computer problem?
if you are running WinXP and you want to install a currently supported C++ redistributable runtime, then you may out of luck. Sorry, not my doing.
Maybe this would help:
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170
You may need or need to create a Microsoft account to access the link.
if you are running WinXP and you want to install a currently supported C++ redistributable runtime, then you may out of luck. Sorry, not my doing.
Maybe this would help:
- Windows XP Support: Microsoft ended support for Windows XP on April 8, 2014. Current versions of the Visual C++ Redistributable for Visual Studio 2015-2022 only support Windows Vista, 7, 8.1, 10, and 11. The last version of the Visual C++ Redistributable that works on Windows XP shipped in Visual Studio 2019 version 16.7 (file versions starting with 14.27). The Redistributable is available in the my.visualstudio.com Downloads section as Visual C++ Redistributable for Visual Studio 2019 (version 16.7). Use the Search box to find this version. To download the files, select the platform and language you need, and then choose the Download button.
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170
You may need or need to create a Microsoft account to access the link.
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Thank you! 😀
It has been so long I forgot how to check, then your question, suddenly came to me.
I think see an issue, installed x86...