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Anyone measure a 5V4 warm up time? It is not specified anywhere.
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...The only definition of warm up time I've ever seen for consumer grade tubes was specific to the heater as applicable to series heater strings. No reference whatsoever to B+ "rise time" of consumer grade rectifiers or conduction within signal / power tubes. OTOH, specs for big industrial / transmitter tubes address the warm up issue indirectly by stating time period filament current (and cooling system) must be "on" prior to application of electrode voltages.
There is some variability in the different brands so if you really want to know, just put your meter probe with an alligator clip adapter or a wire grabber tip on C1 of the power supply then turn on the amp and time or countoff the seconds before full voltage is reached.
The amp is in the design stage. With choke input power supply, I do not want the B+ to rise as a capacitor input power supply. The power tubes warm up in 11 seconds. If 5V4 is 10 seconds, the partial current draw of the power tubes should be enough for Crit at the choke.
I find that with a 5v4 there is a little voltage overshoot when the B+ comes up. Maybe about 10 to 20%. I actually measured it in my amps, and built extra surge voltage in the power supply.
But, with the Mullard and GE 5AR4 ( I did not measure the Sylvania) the B+ ramp up is over 20 seconds around 30 for the Mullard. So there is no overshoot or voltage surge. I do not know about the currently made 5ar4 and i did not measure any of those. cheers, Dak
Jim
If you use DHT power tubes,they will warm up immediately.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
I am using 6V6GT tubes
If you use a center tapped secondary on the high voltage,just put a switch on the CT ground or a delay so that when the output tubes are warmed up,you will be ready by just throwing the switch or having a relay set on delay.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
I could do that with a B+ switch.
Also throwing a switch will usually cause a "thump" and seeing that thump on your speakers can be frightening.
Are you making a single ended or pp amp? If se, a 6106 will be adequate and has a very long 40+ seconds before fully conducting.
One of the Cary/AES amps do it that way with the switch on the CT and I didn't remember it causing a thump but it may have been on a preamp.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
Perhaps I will use the switch to turn on the rectifier tube filaments.
Take a look.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
Usually around 10 seconds before the voltage comes up.
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