audio-talk

My Dad never lied. I was with a military veteran in the cafe yesterday. He used to be on qra when the Lightning and I think it was Jaguar. He is one of the few of many people in Scarborough riding around on ride on scooters. He is one of the his because in the 60’s he was returning fast desent to ...

More food for thought.

Sadly the pp35nn is ony 2.4 watt pp.

The 300b looks very worthy; I have a matched quad. Just one quad but some other matched doubles, so could make an amp to last to my end of life.

But anyway, the 2a3 figures look worthy at 10 watts, I could put a quad of 6b4g’s in.

Yes ...

He sent Octals afterwards.

So to recap, the vade mecum states 250v for triode ab, which is a little confusing because it allows a 375v potential between g2 and g1. So I think the 300v anode and g2 combined ought to be OK as per ETF 6.

So to recap.

https://i.ibb.co/nNfby33Z/IMG-2622.png
https ...

Just bagged two more PL38 new boxed military version £42 delivered. The xx 38 is a superb valve. I found I had two boxed Mullard NOS for the preamp driver project. So had a scan for backup bottles or bottles for PP. as their resistance is 1100 they would go in the QUad II project since the triode ...

Its not a hill worth talking about. I’ll carry on doing what works for me and not bother to talk about it.

Nick Ive done this more than twice without connecting a load, it works. I have one in my bench supply sharing the mains with the big 500mA power transformer. I can’t remember why but its still there and it set the primary voltage exactly right.

When I’ve done this one I’ll photograph it, and the ...

About 25 v torroid secondary in series with the primary to reduce the b+ and I’m there.

But as the two cores are not coupled, the 25v torroid will only reduce the voltage if its under load, the voltage out of the two transformers will be very dependent on the load on the two transformers ...

Here is the 15+15 30 Watt transformer

https://i.ibb.co/TxtbJv0Q/IMG-2608.jpg

two PL38 draw 18 watts. Adding a 5 volt winding will make the total 28w with the 5R4 with the 5u4 33 watts. As the primary is 230v the 30v side will go high but I doubt that matters to the PL 38’s. So the 5v winding if ...

I’m actually using pl38’s in this amp so ordered a torroid 15v x 2 to make 30v which has spare capacity so I’ll wind 5v for the rectifier on that and buy a low value 6v for the two 6j5’s.

https://i.ibb.co/bjTjc7dY/image.jpg

https://i.ibb.co/1GR8hWbw/image.jpg

About 25 v torroid secondary in ...

OK I have a 625-0-625 transformer but I need 570-0-570 so I lower the primary by sharing it with another transformer and then I meet the Black Gate voltage limits including the start up peak. Meaning the b+ is what it says on the signal section schematic.

https://i.postimg.cc/hjR3jmC2/IMG-0562.jpg ...

Oh buggeration, something isn’t right.

This is the choke input power supply.

https://i.ibb.co/9mw9kS7W/IMG-2607.jpg

And this is the b+ I require for the signal section to achieve 4.9 watts stand alone, and actually sufficient voltage swing for full power output of the GM70.

I shall have to go ...

The components are shuffling around the various pre punched holes which are perfect for octal bases. The power transformar was changed to enable the decision to blend the requirements for a reasonable SE power out used daily at home, and the necessary voltage swing to power the GM70 output stage ...

Excellent! :lol:


From a YouTube viddy, re 'the American bubble' (there are several viddys about this)


@harry9392 4 days ago
An American asked me on FB who did I vote for, I said I didn't vote. And I was called a lot of names. And then he asked me what state I was in. Told him Northern Ireland ...

This one is a genuin story from my father’s time as a house Doctor at Wallsend Hospital where Mum and Dad lived when I was born, which classes me as a Geordie but I dont speak that way because after my Dad qualified as a GP he got his first practice in rural Hampshire when I was 2 years old.

So you ...