The Bias Rite seems to be extinct...

MrCoolGuy

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I'm tired of biasing amps manually. I've learned a lot doing it that way, but jeez...
And from what I hear the bias rites were the best for a few reasons... anyone have one for sale? If not, whats another good option?
 

telemnemonics

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Was that like the bias probe and other devices that plug into one or two tube sockets with the power tubed plugged in and either a meter or two or banana plugs to hook to your meter?

Seems to be numerous sources, never decided which to buy.
 

cherryburst1

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With all the variables in modern tube production from over there, today's tubes are all over the place. There just isn't no such thing as a arbitrary one size fits all adjustment. When I dial one in, I usually check cathode currents, etc just out of curiosity. It's never to the published spec. Sometimes it's more, sometimes it's less.
 

Milspec

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I have a new one in box still, but was unaware that they stopped building them. I have an earlier version that I have been using for years, I do think they were the best of their kind.

That said, I am not letting my extra one out of sight.
 

SnidelyWhiplash

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Are you referring to the Weber Bias Rite? Hasn't been made for years, I believe. My friend has one & has used it for quite sum time. I should have bought a bias tool from a company called Amp-Head, now sadly defunct. Always heard they made good stuff. :(
 
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J. Bonkosky

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Just make a socket adapter(s) and get two inexpensive multi meters for a volts reading and an amps reading. Here is a link for octal bases https://www.tubesandmore.com/products/tube-base-8-pin-octal-125-diameterif you don’t want to pull them off a dead octal dual triode or similar. All you need is an octal socket wired in and glued to the base with leads coming out for plate voltage and current readings.
 

Jon Snell

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It is far easier to fit 1Ohm resistors in between the cathode and ground on each valve base; pin 8 to ground. Every millivolt equals a milliamp. Subtract the screen grid dissipation from the reading. The value is on the valve data sheet.
1 Ohm 1W resistor is a penny or so. A valve current tester can be expensive!
 
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SoK66

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Back in the late 2000s I got a probe called the Compu-Bias from Mission Amps. An excellent product that is also sadly no longer in production. Shows plate voltage, milliamps and wattage. The guy had an issue with his probes failing and I'm not sure if he ever worked it out. I have a spare set if the ones I have ever fail.

In the 90s I got one from Alessandro that is really just a couple of VU meters showing milliamps and two probes.
 

SnidelyWhiplash

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I have a BiasPro single socket bias probe.& a SRS PV one. Bought both off Ebay. They work well. I would like to have a dual bias tester, though.
 

PCollen

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Are you referring to the Weber Bias Rite? Hasn't been made for years, I believe. My friend has one & has used it for quite sum time. I should have bought a bias tool from a company called Amp-Head, now sadly defunct. Always heard they made good stuff. :(

sum..? Autocorrect will get you, sooner or later.
 

MrCoolGuy

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Was that like the bias probe and other devices that plug into one or two tube sockets with the power tubed plugged in and either a meter or two or banana plugs to hook to your meter?

Seems to be numerous sources, never decided which to buy.
Yes, but the bias rite was able to show RMS output watts and other things that some meters dont.
 

MrCoolGuy

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Just make a socket adapter(s) and get two inexpensive multi meters for a volts reading and an amps reading. Here is a link for octal bases https://www.tubesandmore.com/products/tube-base-8-pin-octal-125-diameterif you don’t want to pull them off a dead octal dual triode or similar. All you need is an octal socket wired in and glued to the base with leads coming out for plate voltage and current readings.
That is not all you need... if that was all I needed, I would just use my dmm probes. Good bias meters show current.
 

MrCoolGuy

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I have a new one in box still, but was unaware that they stopped building them. I have an earlier version that I have been using for years, I do think they were the best of their kind.

That said, I am not letting my extra one out of sight.
Then why say anything?
 

MrCoolGuy

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Are you referring to the Weber Bias Rite? Hasn't been made for years, I believe. My friend has one & has used it for quite sum time. I should have bought a bias tool from a company called Amp-Head, now sadly defunct. Always heard they made good stuff. :(
Yes. And yes, I know they dont make them anymore, thst why I'm asking on here instead of Amazon.
 

MrCoolGuy

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It is far easier to fit 1Ohm resistors in between the cathode and ground on each valve base; pin 8 to ground. Every millivolt equals a milliamp. Subtract the screen grid dissipation from the reading. The value is on the valve data sheet.
1 Ohm 1W resistor is a penny or so. A valve current tester can be expensive!
Agreed. Not everyone wants that in their amp. And some amps with pcb's arent that easy to install. That said, that is the way I do my amps.
 

cherryburst1

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That is not all you need... if that was all I needed, I would just use my dmm probes. Good bias meters show current.
It's unfortunate no one knows what the real current draw should be, given any modern tube.
All depends on how much cat hair was used to extend metal parts production that day...
 




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