Search found 8957 matches

by Paul Barker
Sat Apr 13, 2024 9:27 pm
Forum: Everyones Projects
Topic: Distortion 2 to 3 W DHT,IDHT,Multigrid idht.
Replies: 3
Views: 92

Re: Distortion 2 to 3 W DHT,IDHT,Multigrid idht.

OK so this has led me back to the 801a amplifier. 535v - 34 mA A2 operation. Get 5.6 watts. Use the tribute OPT’s.
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by Paul Barker
Sat Apr 13, 2024 7:44 pm
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

This is what Stephie said about the negative in his example 3rd

“Notice the minus sign. This indicates that the harmonic content subtracts from the fundamental (flattening it) when the fundamental is at its crest. This *usually* happens on third harmonic distortion in tubes.”
by Paul Barker
Sat Apr 13, 2024 2:57 pm
Forum: Everyones Projects
Topic: Distortion 2 to 3 W DHT,IDHT,Multigrid idht.
Replies: 3
Views: 92

Re: Distortion 2 to 3 W DHT,IDHT,Multigrid idht.

In my book the EL34 wins.
by Paul Barker
Sat Apr 13, 2024 2:48 pm
Forum: Everyones Projects
Topic: Distortion 2 to 3 W DHT,IDHT,Multigrid idht.
Replies: 3
Views: 92

Distortion 2 to 3 W DHT,IDHT,Multigrid idht.

Right, its getting surprising. Ive probably given up on repurposed sweep tubes. But now, as the EL34 sounds so great at 2.1 watts Ive drawn up the distortion camparrisons of three valves of which you’d expect the dht’s to win. https://i.postimg.cc/xdNLvBzW/IMG-1236.jpg https://i.postimg.cc/cLBq9F8C/...
by Paul Barker
Sat Apr 13, 2024 1:23 pm
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

Yes Steve Im going off the EL84 aswell. But the EL34 at 2.1 watts is a keeper. Its the winner of this excercise. I see no point building an amp loaded with odd order distortion. I cant go out so I’ll play with other characteristic curves at 2 watts. Its a shame I dont think I can get more than a wat...
by Paul Barker
Sat Apr 13, 2024 1:13 pm
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

So I shifted the EL36 operating point to 2.3 watts and to highest current I could, also pushed dissipation up to 20w limit; the 3rd h distortion speaks for itself. https://i.postimg.cc/152zYVG2/IMG-1237.jpg https://i.postimg.cc/6pZQs6z3/IMG-1238.jpg I don’t see a 300b challenger. This will not be th...
by Paul Barker
Sat Apr 13, 2024 12:03 pm
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

I’m sorry I was struggling with the 3rd harmonic distortion formula, so went back to Stephies teaching on distortion, read it multiple times, added 4th harmonic so I now have a spreadsheet that calculates 2nd 3rd and 4th. Stephie explains the negative figures. They are not a calculation error. I gue...
by Paul Barker
Fri Apr 12, 2024 6:04 pm
Forum: News
Topic: Diana’s PIP has been approved
Replies: 10
Views: 277

Re: Diana’s PIP has been approved

Ah, so I could claim pension tax credits if I don’t work. I probably will.
by Paul Barker
Fri Apr 12, 2024 2:28 pm
Forum: News
Topic: Diana’s PIP has been approved
Replies: 10
Views: 277

Re: Diana’s PIP has been approved

I get more than £81 state pension so “you will not get any carers allowance”

So that wont be claimed and as before its better to work.
by Paul Barker
Fri Apr 12, 2024 10:14 am
Forum: News
Topic: Diana’s PIP has been approved
Replies: 10
Views: 277

Re: Diana’s PIP has been approved

Yes, thank you? I could have always had it as I registered as her carer 2010 when she first went into a coma and came back not knowing our wedding or honeymoon. . It just suited me to work instead. Yes I’ll get that changed. Probably by phoning the local council as thats where I had to register.
by Paul Barker
Fri Apr 12, 2024 9:21 am
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

16uF ultrapath cap ordered QTY 2
by Paul Barker
Fri Apr 12, 2024 8:51 am
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

Re: EL36 SE Triode from ETF 2006 build

I’ll consider moving the el34 out of its chassis and fit it into the new smaller chassis. Depending if I can reduce the bypass cap as it would require 6 big poly caps as it stands and Im not using electrolytics, Ive heard better, Im not going backwards. The bypass cap calk for existing cap in the El...
by Paul Barker
Fri Apr 12, 2024 7:56 am
Forum: Everyones Projects
Topic: EL36 SE Triode from ETF 2006 build
Replies: 10
Views: 218

EL36 SE Triode from ETF 2006 build

https://i.postimg.cc/L8DyLPnR/IMG-1230.jpg https://i.postimg.cc/CMn6Xd6H/IMG-1231.jpg with a couple of changes, yet to put ultrapath cap value in as need to get all facts and I’ll do the calcs on the bypass cap in the same process. Im sure 330 is excessive. The grid choke speaks for itself. https:/...