6V6. One of the most well known and dare I say "loved" tubes of low audio output tubes(low compared to say an 810). I'd read about beam power tubes in quite a few different places and had simply marveled at the novel design that had produced so much more from a tube of that size. Appearently I skimmed over the space charge effect every single time. I've been hassling the good (and forgiving) people in this forum for quite some time begging for an answer to why my audio output push pull 6V6's had a higher screen voltage than plate voltage. No one answered I think because they wanted me to go hunting for myself. I had honestly forgotten they were beam power until a few days ago(you always see them drawn like a regular pentode on a schematic, and you sure cant see inside the tube). I just reread the section on beam power tubes from that wonderful little orange ameco book I'm sure everyone has a copy of, and I had that eureka moment where it became clear to me. Thanks for pushing me fella's. Sorry for all the whining

Hi

6V6's sometimes have higher screen voltage than plate since both are supplied from the same point in a power supply. The screen connects directly to B+ while plate goes through an output transformer. This output transformer has resistance and drops some voltage.

Norm

:6V6. One of the most well known and dare I say "loved" tubes of low audio output tubes(low compared to say an 810). I'd read about beam power tubes in quite a few different places and had simply marveled at the novel design that had produced so much more from a tube of that size. Appearently I skimmed over the space charge effect every single time. I've been hassling the good (and forgiving) people in this forum for quite some time begging for an answer to why my audio output push pull 6V6's had a higher screen voltage than plate voltage. No one answered I think because they wanted me to go hunting for myself. I had honestly forgotten they were beam power until a few days ago(you always see them drawn like a regular pentode on a schematic, and you sure cant see inside the tube). I just reread the section on beam power tubes from that wonderful little orange ameco book I'm sure everyone has a copy of, and I had that eureka moment where it became clear to me. Thanks for pushing me fella's. Sorry for all the whining

Sometimes, you will see a pair of 6V6s in a circuit where the screens are tapped off of the output tramsformer with the plates. If I remember correctly, this is called a "Williamson" circuit. The plates work at a higher impedence than the screens, but at a lower DC Voltage.
Lewis

:Hi
:
: 6V6's sometimes have higher screen voltage than plate since both are supplied from the same point in a power supply. The screen connects directly to B+ while plate goes through an output transformer. This output transformer has resistance and drops some voltage.
:
:Norm
:
::6V6. One of the most well known and dare I say "loved" tubes of low audio output tubes(low compared to say an 810). I'd read about beam power tubes in quite a few different places and had simply marveled at the novel design that had produced so much more from a tube of that size. Appearently I skimmed over the space charge effect every single time. I've been hassling the good (and forgiving) people in this forum for quite some time begging for an answer to why my audio output push pull 6V6's had a higher screen voltage than plate voltage. No one answered I think because they wanted me to go hunting for myself. I had honestly forgotten they were beam power until a few days ago(you always see them drawn like a regular pentode on a schematic, and you sure cant see inside the tube). I just reread the section on beam power tubes from that wonderful little orange ameco book I'm sure everyone has a copy of, and I had that eureka moment where it became clear to me. Thanks for pushing me fella's. Sorry for all the whining

Smart idea. Makes use of the wasted screen power. I had an idea to put the output transformer in the cathode circuit in a special way that would still allow the tube to have gain, but I haven't tried it. It, too, if it worked properly, would make use of both screen and plate current, and might have more clarity, since all electrons leave the cathode in a uniform manner, but get all jumbled up on their way to the plate, and they don't all necessarily make it to the plate at the same time like they left the cathode.

....Also, regarding beam vs. regular pentodes, most of the radios I own with regular pentodes (6K6, 6F6, 41, 42, 1LB4, etc.) also have their screens tied directly to the same B+ that feeds the output transformer. The output transformer is the reason why the voltage seen at the plate is lower than that at the screen, even though they both derive power from the same B+ point (as others have said).

T.

Yes, being relatively new to tubes, this threw me off for quite some time. I see a lot of them with the same voltage, alot with the screen slightly lower, and then some with vastly lower voltages. I did recognize the drop across the rest of the coil making the screens higher than the plate. Its what caused me to check the schematic in the first place. I had forgotten they were beam tubes and have always heard that a higher screen voltage than plate voltage would burn up a pentode in nothing flat. Thanks for all the responses.

:Smart idea. Makes use of the wasted screen power. I had an idea to put the output transformer in the cathode circuit in a special way that would still allow the tube to have gain, but I haven't tried it. It, too, if it worked properly, would make use of both screen and plate current, and might have more clarity, since all electrons leave the cathode in a uniform manner, but get all jumbled up on their way to the plate, and they don't all necessarily make it to the plate at the same time like they left the cathode.
:

:....Also, regarding beam vs. regular pentodes, most of the radios I own with regular pentodes (6K6, 6F6, 41, 42, 1LB4, etc.) also have their screens tied directly to the same B+ that feeds the output transformer. The output transformer is the reason why the voltage seen at the plate is lower than that at the screen, even though they both derive power from the same B+ point (as others have said).
:
:T.

Im sure you meant "impedance" and not resistance. The dc drop of the transformer wire would be almost negligible.

:Hi
:
: 6V6's sometimes have higher screen voltage than plate since both are supplied from the same point in a power supply. The screen connects directly to B+ while plate goes through an output transformer. This output transformer has resistance and drops some voltage.
:
:Norm
:
::6V6. One of the most well known and dare I say "loved" tubes of low audio output tubes(low compared to say an 810). I'd read about beam power tubes in quite a few different places and had simply marveled at the novel design that had produced so much more from a tube of that size. Appearently I skimmed over the space charge effect every single time. I've been hassling the good (and forgiving) people in this forum for quite some time begging for an answer to why my audio output push pull 6V6's had a higher screen voltage than plate voltage. No one answered I think because they wanted me to go hunting for myself. I had honestly forgotten they were beam power until a few days ago(you always see them drawn like a regular pentode on a schematic, and you sure cant see inside the tube). I just reread the section on beam power tubes from that wonderful little orange ameco book I'm sure everyone has a copy of, and I had that eureka moment where it became clear to me. Thanks for pushing me fella's. Sorry for all the whining

Perthrow,

Norm is right. The output transformer has DC resistance which is not the same as AC resistance (impedance).

Radiodoc
*****************

:Im sure you meant "impedance" and not resistance. The dc drop of the transformer wire would be almost negligible.
:
:
::Hi
::
:: 6V6's sometimes have higher screen voltage than plate since both are supplied from the same point in a power supply. The screen connects directly to B+ while plate goes through an output transformer. This output transformer has resistance and drops some voltage.
::
::Norm
::
:::6V6. One of the most well known and dare I say "loved" tubes of low audio output tubes(low compared to say an 810). I'd read about beam power tubes in quite a few different places and had simply marveled at the novel design that had produced so much more from a tube of that size. Appearently I skimmed over the space charge effect every single time. I've been hassling the good (and forgiving) people in this forum for quite some time begging for an answer to why my audio output push pull 6V6's had a higher screen voltage than plate voltage. No one answered I think because they wanted me to go hunting for myself. I had honestly forgotten they were beam power until a few days ago(you always see them drawn like a regular pentode on a schematic, and you sure cant see inside the tube). I just reread the section on beam power tubes from that wonderful little orange ameco book I'm sure everyone has a copy of, and I had that eureka moment where it became clear to me. Thanks for pushing me fella's. Sorry for all the whining