Hi. I'm trying to establish whether the RCA8000 Power Triode is equivalent to the RCA810 Transmitting Triode. Reason being that I'm looking at purchasing a pair of push-pull RCA8000 mono block amps and I want to make sure that replacement tubes won't be an issue. HT in the amps is probably 800V. Currently trying to locate the schematics but it's probably one of the ones in this thread: 8000 electron tube.
The tubes look the same and the bases and pin-outs are the same but there are differences between some parameters. Question is whether the tubes would be interchangeable in a push-pull amp.
Salient characteristics are shown side-by-side below.
So, the Amplification Factors are different but the grid voltage and plate current aren't specified for the 810.
There are minor differences in interelectrode capacitances.
The AF Power Amplifier Maximum Ratings are the same.
For "Typical Operation" the DC Grid voltages are completely different. The Maximum signal driving power differs by about 35%. Other parameters are very close.
I've also superimposed the anode characteristics. The 810 tube curves initially show a higher current but show a lower current above 800V or so.
>>>>>>>>8000>810
400V/+60V 32mA 34mA
800V/+60V 49mA 45mA
The variation probably isn't more than you'd see between tubes of the same designation.
My guess is that you could replace a pair of 8000s with a pair of 810s but wouldn't want to mix them.
What does the forum think?
The tubes look the same and the bases and pin-outs are the same but there are differences between some parameters. Question is whether the tubes would be interchangeable in a push-pull amp.
Salient characteristics are shown side-by-side below.
So, the Amplification Factors are different but the grid voltage and plate current aren't specified for the 810.
There are minor differences in interelectrode capacitances.
The AF Power Amplifier Maximum Ratings are the same.
For "Typical Operation" the DC Grid voltages are completely different. The Maximum signal driving power differs by about 35%. Other parameters are very close.
I've also superimposed the anode characteristics. The 810 tube curves initially show a higher current but show a lower current above 800V or so.
>>>>>>>>8000>810
400V/+60V 32mA 34mA
800V/+60V 49mA 45mA
The variation probably isn't more than you'd see between tubes of the same designation.
My guess is that you could replace a pair of 8000s with a pair of 810s but wouldn't want to mix them.
What does the forum think?
