Found a couple of these in my Dad's tube stash. Any opinion on how this damper tube would perform versus a 5ar4 as a rectifier tube? More or less sag.
Look closely at the 6BY5 datasheet. Notice that it's good for 175 mA. of DC per plate. IMO, forward drop will be somewhat less than in a 5AR4/GZ34.
Compared with other damper types, the heater to cathode insulation in the 6BY5 is weak. Therefore, it makes sense (IMO) to use a dedicated 6.3 VAC winding of good HIPOT rating to feed the heater and tie the cathodes to an end of the heater. That replicates the internal construction of the 5AR4 and eliminates heater to cathode insulation breakdown worries.
Compared with other damper types, the heater to cathode insulation in the 6BY5 is weak. Therefore, it makes sense (IMO) to use a dedicated 6.3 VAC winding of good HIPOT rating to feed the heater and tie the cathodes to an end of the heater. That replicates the internal construction of the 5AR4 and eliminates heater to cathode insulation breakdown worries.
I have a bunch of other dampers. Any I should look for that would be better? I know I would need 2 instead of the 1 6BY5.
While some seem to like the 6BY5GA I much prefer the 5AR4 or what I am more used to the Mullard equivalent =GZ34 which is a reliable tube ( no idea if modern copies are any good I am referring to Mullard) .
A warning comes with the 6BY5GA that the voltage difference in a negative respect between the cathode and heater has an upper limit of 450 volts , actually much less is advised --that's RCA advice .
I have figures for the GZ34 which is the UK equivalent and 60uF is advised for capacitor input at 250ma --limiting value Ia (pk) 750ma
A warning comes with the 6BY5GA that the voltage difference in a negative respect between the cathode and heater has an upper limit of 450 volts , actually much less is advised --that's RCA advice .
I have figures for the GZ34 which is the UK equivalent and 60uF is advised for capacitor input at 250ma --limiting value Ia (pk) 750ma
@duncan2
You will find the affordable Sovtek 5AR4 to be highly suitable, IF you implement the series SS diode tweak. On grounds of general principles, I suggest UF4007s, instead of the 1N4007s shown. Less noise, from the outset, can't be bad.
Claims have been made that the series SS diode tweak allows a bit more service to be squeezed out of well used and worn rectifier specimens. I can neither verify nor disparage said claims.
You will find the affordable Sovtek 5AR4 to be highly suitable, IF you implement the series SS diode tweak. On grounds of general principles, I suggest UF4007s, instead of the 1N4007s shown. Less noise, from the outset, can't be bad.
Claims have been made that the series SS diode tweak allows a bit more service to be squeezed out of well used and worn rectifier specimens. I can neither verify nor disparage said claims.
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The hassle you will have is satisfying the needs for the heater supply of a non-standard rectifier compared with a currently manufactured variety.
If you are specifying your own transformers for the project - and some manufacturers do not charge much for that service, then you could get a 6,3V 3A winding with a 5V tap for rectifier purposes.
If you are specifying your own transformers for the project - and some manufacturers do not charge much for that service, then you could get a 6,3V 3A winding with a 5V tap for rectifier purposes.
I really like the 6BY5 and have used it a lot. Sometimes in pairs. Quite a bit of voltage drop. I've also used 6DT4 but prefer the 6BY5. Ideal for a preamp, but can be used in pairs for amps.
Go for it!
Go for it!
The 6DQ4 is quite useful too, and at 1.2A, not too hungry on heater draw. Adding a suitable 6 or 12 volt transformer is easy enough though.
And a pair in FWCT (the usual) configuration are good for >300mA.
The same pair have been in an experimental SE amp for years without issue.
And a pair in FWCT (the usual) configuration are good for >300mA.
The same pair have been in an experimental SE amp for years without issue.