Audio Asylum Thread Printer
Get a view of an entire thread on one page
|For Sale Ads|
In Reply to: RE: Eico HF-30 question posted by gkargreen on May 29, 2017 at 08:32:21
310v rail voltage is way too low. The source voltages should be 360v,350v,and 320v. This would also explain your lower cathode voltages.
Was this originally the 6C4/6AV6 amp or don't you know?
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
Hi, Michael, and thanks! This was originally the 6AV6/6C4 version that someone in the past had wired up the PS to be the version with the 7247, don't really see a problem with that. The plate and screen is right on the money, the rail after the 33K is 281 v, whereas the schematic notes 310, this is for the 7247 version, don't know what the voltages are supposed to be for the 6C4/6AV6 version (this voltage feeds the front end tubes) Also, the cathode for the 6BQ5 is 11.6 v, once again I don't know what it should be for the 6C4/6AV6 version, but the 7247 schematic it is 15 volts. Thanks, Randy
There is no reason to believe that the voltages would differ. The triode in a 6AV6 is the "same" as those in a 12AX7. The triode in a 6C4 is the "same" as those in a 12AU7. The 7247/12DW7 is 1/2 'X7 and 1/2 'U7.
BTW, the 2 tiny diodes in the 6AV6 would be grounded out.
Post a Message!
This post is made possible by the generous support of people like you and our sponsors: