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Been out having fun today!
#11

Well after having a closer look there isn't enough bias on the 47. Only about -4v and it has 260v on the plate. Transformer is rated @ 40ma. Measured the total HV current and it was 46ma. So what I did was remove the hv ct from ground and put in a few resistors. What did was give me a tap so I could come up with -15v for the 47 tube bias and it lowers the total hv. As it stands I got it down to 36ma total and the hv is about 190v.
Overall I'm happy with it. It still runs a bit warm but isn't unconformable to touch. Audio sounds good and clean with plenty of volume.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
Been out having fun today! - by 7estatdef - 05-09-2011, 05:12 PM
Re: Been out having fun today! - by Uffda - 05-09-2011, 06:28 PM
Re: Been out having fun today! - by TA Forbes - 05-09-2011, 10:44 PM
Re: Been out having fun today! - by 7estatdef - 05-10-2011, 06:00 AM
Re: Been out having fun today! - by TA Forbes - 05-10-2011, 10:44 PM
Re: Been out having fun today! - by 7estatdef - 05-12-2011, 10:36 PM
Re: Been out having fun today! - by 7estatdef - 05-14-2011, 05:17 PM
Re: Been out having fun today! - by 7estatdef - 05-18-2011, 08:18 PM
Re: Been out having fun today! - by Arran - 05-19-2011, 12:49 AM
Re: Been out having fun today! - by 7estatdef - 05-19-2011, 03:30 PM
Re: Been out having fun today! - by 7estatdef - 05-23-2011, 12:27 PM



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