What Do these Numbers Mean
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bob barcus
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What Do these Numbers Mean
I have a quad of Matsushita 6Ca7 coming and the guy in Japan gave me these numbers VG 4.0 IK 77 GM 9.6 what does that mean,is that good ? Bad?
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Kevin
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Re: What Do these Numbers Mean
Whether they're good or bad depends on which values would represent 100%, given those test conditions. Your tubes tested 9.6mA/V in the way of transconductance and 77mA in the way of cathode current, it seems. Usually plate current is measured. I guess screen current is included here...
Numbers like these usually imply a low plate voltage like 250V and a bias voltage of -12V or so, where the data sheets usually state 100mA and 11mA/V as 100%. Although Vg is being stated as 4, so I don't know...
If you're concerned, I would ask him or her which values represent 100% in this situation.
Have you seen pics? I would say that physical appearance is as important as test scores. The Matsushitas up for grabs usually look pretty good, as opposed to a lot of the fried Mullards which people are always trying to sell...
Numbers like these usually imply a low plate voltage like 250V and a bias voltage of -12V or so, where the data sheets usually state 100mA and 11mA/V as 100%. Although Vg is being stated as 4, so I don't know...
If you're concerned, I would ask him or her which values represent 100% in this situation.
Have you seen pics? I would say that physical appearance is as important as test scores. The Matsushitas up for grabs usually look pretty good, as opposed to a lot of the fried Mullards which people are always trying to sell...
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bob barcus
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Re: What Do these Numbers Mean
I just got them yesterday and they look brand new,Tube tramp said that they are really good tubes. Now I just need to fire them up.I have had alot better buying E. 
German dimple tops and these Matsushia's than with the Mules on ebay
German dimple tops and these Matsushia's than with the Mules on ebay-
jonamojo
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Re: What Do these Numbers Mean
no doubt, out of the 3 pairs of xf2's I bought 2 tubes fried within a month, ended up with 1 good pairbob barcus wrote:I just got them yesterday and they look brand new,Tube tramp said that they are really good tubes. Now I just need to fire them up.I have had alot better buying E.
