Had this Yaquin MS300B for a bit of time... The entire summer its been on my bench and I have had zero time until a week or three ago...
Most of my learning (aka mistakes) have been on this but think I'm getting a grip...
Very early on I followed some posts elsewhere regarding suggestions, learned that as it is now (after some TLC) is reasonably well set up.
Today finally, the Amp is now for lack of a better term "blue printed". Most of important values have been measured and documented.
I know this is not how the amp sounds (Great to my ears!), but more of a inventory type of check...
Attached is my marked up PDF. When you see two readings, the 1st is always the left channel. plan to use this info in my very near future trouble shooting.
Whats bugging me the most right now, is the 300B heater voltage varies and is not matched left/right.. Not sure if this matters, but I cant imagine it doesn't....
I have not had hours to spend, been more like 20-45 min here and there.
Each time I let the amp warm up for at least 10 min.. Left channel 300B varies from 4.8-5.3 and right channel 5.2-5.6.
Every time the reading shows left is lower than right... Did NOT switch tubes around yet, wanted to get as much as a snapshot as I could....
I hoped you fine folks may gander at the attached and let me know if anything is glaringly out or wrong value wise, if anything looks like an improvement should be considered etc...
Most of my learning (aka mistakes) have been on this but think I'm getting a grip...
Very early on I followed some posts elsewhere regarding suggestions, learned that as it is now (after some TLC) is reasonably well set up.
Today finally, the Amp is now for lack of a better term "blue printed". Most of important values have been measured and documented.
I know this is not how the amp sounds (Great to my ears!), but more of a inventory type of check...
Attached is my marked up PDF. When you see two readings, the 1st is always the left channel. plan to use this info in my very near future trouble shooting.
Whats bugging me the most right now, is the 300B heater voltage varies and is not matched left/right.. Not sure if this matters, but I cant imagine it doesn't....
I have not had hours to spend, been more like 20-45 min here and there.
Each time I let the amp warm up for at least 10 min.. Left channel 300B varies from 4.8-5.3 and right channel 5.2-5.6.
Every time the reading shows left is lower than right... Did NOT switch tubes around yet, wanted to get as much as a snapshot as I could....
I hoped you fine folks may gander at the attached and let me know if anything is glaringly out or wrong value wise, if anything looks like an improvement should be considered etc...
Attachments
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Every component in your heatercircuit has tolerance, will differ, and those differences can add up.
Transformer windings, diode forward voltages, eĺectrolyte capacitors çapacitance and equivalent series resistance, tubes heater resistance.
Since you have 2 "equal" heatercircuits find out by swapping one thing at a time and measure the voltage difference. Start with the easist, the tube
Transformer windings, diode forward voltages, eĺectrolyte capacitors çapacitance and equivalent series resistance, tubes heater resistance.
Since you have 2 "equal" heatercircuits find out by swapping one thing at a time and measure the voltage difference. Start with the easist, the tube