Search found 9423 matches

by Paul Barker
Fri Dec 13, 2024 7:02 pm
Forum: Everyones Projects
Topic: 833A (GU-48) Amp
Replies: 1256
Views: 576328

Re: 833A (GU-48) Amp

https://i.ibb.co/7VfBfbS/IMG-1850.jpg

I’ll get my big 3kv power transformers dusted off out of the lockup. It has been to Eggborough and Owston and meetings in my dining room last Century.

Might be able to get 1k5 polyprops more easily than 3kv and stack them. I have 8 anyway at 50uF so that ...
by Paul Barker
Fri Dec 13, 2024 4:02 pm
Forum: Everyones Projects
Topic: Converting EL38 amp to 300b Amp
Replies: 64
Views: 12863

Re: Converting EL38 amp to 300b Amp

https://i.ibb.co/PNYvPD1/IMG-9944.jpg
https://i.ibb.co/S3xzngp/IMG-9943.jpg
https://i.ibb.co/TcBdBdK/IMG-9945.jpg

Above you can see what I called semens, are Dubilier pio caps. The Russian pio 0.1 uF caps arrived.

The pair of power transformers and chokes make it monoblock rated transformers ...
by Paul Barker
Fri Dec 13, 2024 1:16 pm
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

For Max. The most dramatic a change of load is the 10y 801a at 30mA 15 watts disipation one chart into 5k load other 10k load.

A bigger difference than a 45 or 6v6.

But a good example to bear in mind loading appropriately.

https://i.ibb.co/nf7qMJT/IMG-1840.jpg
https://i.ibb.co/3h3vrB0/IMG ...
by Paul Barker
Fri Dec 13, 2024 11:44 am
Forum: Jokes
Topic: A little light humour
Replies: 2784
Views: 1530766

Re: A little light humour


When we were newly wedded, Diana went on a course for a week.

I carried my vauxhall viva engine into the bedsit living room stripped it down put new shells on the crank all shells and fitted cords rings had it back in the car before she got home. She never found out.


13 Hamilton Rd Bromley ...
by Paul Barker
Fri Dec 13, 2024 11:40 am
Forum: Jokes
Topic: A little light humour
Replies: 2784
Views: 1530766

Re: A little light humour

When we were newly wedded, Diana went on a course for a week.

I carried my vauxhall viva engine into the bedsit living room stripped it down put new shells on the crank all shells and fitted cords rings had it back in the car before she got home. She never found out.
by Paul Barker
Fri Dec 13, 2024 11:37 am
Forum: Everyones Projects
Topic: Converting EL38 amp to 300b Amp
Replies: 64
Views: 12863

Re: Converting EL38 amp to 300b Amp

Nick wrote: Thu Dec 12, 2024 9:15 am I am sure it was a rhetorical question but
Resistors and coupling caps; Who said they need fixing
I think almost entirely you.
Lol
by Paul Barker
Thu Dec 12, 2024 1:05 pm
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

Good to know.
by Paul Barker
Thu Dec 12, 2024 9:16 am
Forum: Everyones Projects
Topic: Converting EL38 amp to 300b Amp
Replies: 64
Views: 12863

Re: Converting EL38 amp to 300b Amp

OK so back on the 300b amp. I was uncomfortable with the 6j5 lack of load and rather larger ri caused by the lack of bypass cap. I also decided it was worth trying the 6em7 stage at higher than usual voltage but drop the current to 35 mA. That means I dont need to drop the b+ voltage. The 6j5 I ...
by Paul Barker
Thu Dec 12, 2024 6:39 am
Forum: Everyones Projects
Topic: Converting EL38 amp to 300b Amp
Replies: 64
Views: 12863

Re: Converting EL38 amp to 300b Amp

Well to be honest the 801a amp sounded pants compared to the EL38 triode connected SE amp. It had the hammond interstage transformers. That proves nothing but makes one aware of something.

So I went forward using srppcl and cant prove anything but it sounds bloody marvellous. The C’s are Siemans ...
by Paul Barker
Thu Dec 12, 2024 4:57 am
Forum: Jokes
Topic: A little light humour
Replies: 2784
Views: 1530766

Re: A little light humour

My mate subscribes to the trade magazine "Osteopath Monthly".

He has a lot of back issues.
by Paul Barker
Thu Dec 12, 2024 1:14 am
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

Nick wrote: Wed Dec 11, 2024 9:20 pm So remove the center tapped choke and use to resistors. Ok, standard PP driver stage. Not sure where the CCS's come into it?
At the b+ end two ccs one for each pole.
by Paul Barker
Wed Dec 11, 2024 5:23 pm
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

Image
by Paul Barker
Wed Dec 11, 2024 4:56 pm
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

Ok that makes sense Nick. So is that where the ccs comes in you were talking about to Dave was it?

Max yes secondary left open.

Nick, so actually I could use a two power resistors of the value required and b+ to centre tap? Or just use the ccs and have a horizontal. Loadline?

Not that Im goingto ...
by Paul Barker
Wed Dec 11, 2024 11:22 am
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay



But in deciding the driver the 2a3 or px4 were outright winners. The 45 probably has other sound qualities to mitigated its distortion. But its ability to drive the grid of 300b may be insufficient for full output aswell. Its either Sukuma concept and use another 4 300b’s or use 2a3 types. My ...
by Paul Barker
Wed Dec 11, 2024 6:41 am
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 147
Views: 45168

Re: It's time to go full Karna Kay

I was about to build pp 300b but the 8 valves, I would have used 6b4g driver and the biggish pp opt’s used as ct choke for drivers, add to that the big Sowter opt’s. It was as big a boat anchor as an se GM70 SE. So changed my mind.

The bee in my bonnet is you guys all building pp amps full of ...