Why was there no PCC81/82/83?

[Disco Volante]

Second that! Check out the super-rugged PL81A (more linear version of PL81). Ra of 2K5, 20+W in PP... And anode at the top -how HV-cool is that?

 

[Admiral-dk]

Only Spoiler in todays World - is the fact that a lot of 'Modern' ECC81, ECC82 and ECC83 (goes for the US numbered12AT7, 12AU7 and 12AX7 as well) do NOT have a 300mA Heater !!!!
Most of the Russian 'Renamed Models' use 350-400mA => Plugging one of those in a Serial Heater System, and you get a lowered Voltage on those Heaters in that Tube ...!!!!
A good number of Chinese has the same problem ...!!!

Beside being a problem (of variable size - depending on ...) - it can also be a problem in Parallel Heater Circuits if the Transformer can't supply the extra Juice (Amperes) required ....

Per

 

[rock soderstrom]

Only Spoiler in todays World - is the fact that a lot of 'Modern' ECC81, ECC82 and ECC83 (goes for the US numbered12AT7, 12AU7 and 12AX7 as well) do NOT have a 300mA Heater !!!!
Most of the Russian 'Renamed Models' use 350-400mA => Plugging one of those in a Serial Heater System, and you get a lowered Voltage on those Heaters in that Tube ...!!!!
A good number of Chinese has the same problem ...!!!

Beside being a problem (of variable size - depending on ...) - it can also be a problem in Parallel Heater Circuits if the Transformer can't supply the extra Juice (Amperes) required ....

Per

That's interesting, do you know why that is? I mean, they have been building these types of tubes for ages, the specifications are unchanged. Is it a particular technical production challenge or just sloppiness?

 

[Khron]

That's interesting, do you know why that is? I mean, they have been building these types of tubes for ages, the specifications are unchanged. Is it a particular technical production challenge or just sloppiness?

Higher current might mean less wire (for the same thickness/gauge), thus some material & processing cost savings...

 

[rock soderstrom]

Higher current might mean less wire (for the same thickness/gauge), thus some material & processing cost savings...

You mean their motivation is good old greed? You're probably very close to the truth. After all, that is one of the main drivers for stupid decisions.

 

[Khron]

You mean their motivation is good old greed? You're probably very close to the truth. After all, that is one of the main drivers for stupid decisions.

There's no amount of engineering that can't be screwed up by bean-counters...

 

[gyraf]

Those Russian/ Chinese tube types were probably never meant to be copies of ecc81/82/83 - however some of them were "close enough" to be passed off as "equivalents" or "replacements" for expensive western types.

I'd guess its a creative-marketing made flaw