Search found 1095 matches

by Thermionic Idler
Thu Jan 30, 2025 7:25 pm
Forum: Assorted Stuff
Topic: Rozenblit - Transcendent Amps
Replies: 2
Views: 16618

Re: Rozenblit - Transcendent Amps

I've just downloaded the one for the Evermore - 2 monoblocks with 8 EL34's per side.

I've had the Beasts on the shelf since the 300B amps went live - with EL509's now costing £55 a pop from HotRox, that means they now have a retubing cost of £1320 :shock: And I didn't even build it with all 16 ...
by Thermionic Idler
Mon Jan 27, 2025 11:32 am
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 212
Views: 163433

Re: It's time to go full Karna Kay

The boxes are MDF with walnut veneer, the chassis frame itself is solid walnut. That picture is from when the amp was quite new, the walnut has since acquired a slightly deeper, more golden colour with age.
by Thermionic Idler
Sun Jan 26, 2025 7:53 pm
Forum: Everyones Projects
Topic: It's time to go full Karna Kay
Replies: 212
Views: 163433

Re: It's time to go full Karna Kay

Progress update. As well as planning the power supply, I have been trying to figure out how to modify the input stage layout for KT88 drivers to fit.

Tha main issue being that the three existing octal valve sockets that accommodate a 12SN7 and two 6V6's are only 50mm from each other centre-to ...
by Thermionic Idler
Mon Jan 20, 2025 11:51 am
Forum: Suppliers, recommended or not
Topic: Lundahl in the UK
Replies: 3
Views: 26082

Re: Lundahl in the UK

Looks like HiFiCollective has a Lundahl account now too.
by Thermionic Idler
Sun Jan 05, 2025 7:37 pm
Forum: Suppliers, recommended or not
Topic: PTFE hookup wire - help!
Replies: 9
Views: 7551

Re: PTFE hookup wire - help!


If it helps Dave I've a little red and white silver plated copper ptfe wire and could send you a meter or so of each if that's what you need?

This is the red stuff that came from Rapid
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This is the white stuff from Farnell
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20250105_192306.jpg
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I think I've got som yellow ...
by Thermionic Idler
Sun Jan 05, 2025 6:05 pm
Forum: Suppliers, recommended or not
Topic: PTFE hookup wire - help!
Replies: 9
Views: 7551

Re: PTFE hookup wire - help!


Amateur radio rallies are your friend. https://rsgb.org/main/news/rallies/ I bought a carrier bag full of PTFE-covered wire on reels for £10. Beware that the stuff is horrible to strip. And you want solid core for a tight heater twist. Also, https://www.bvws.org.uk/ but you need to become a member ...
by Thermionic Idler
Sun Jan 05, 2025 4:36 pm
Forum: Suppliers, recommended or not
Topic: PTFE hookup wire - help!
Replies: 9
Views: 7551

Re: PTFE hookup wire - help!


Why not use one colour only and identify with different coloured heat shrink or even small zip-ties as tags? Can be positioned at both terminal ends but anywhere else you might find helpful. Just an idea……..

I did think about that as an option, it does seem easier to get hold of heatshrink in ...
by Thermionic Idler
Sun Jan 05, 2025 2:25 pm
Forum: Suppliers, recommended or not
Topic: PTFE hookup wire - help!
Replies: 9
Views: 7551

PTFE hookup wire - help!

During the latest bout of insomnia, I figured out a nice new wiring colour scheme for Project Redwing, which would allow easy differentiation of B+, ground nodes, signal phase, the different heater lines etc.

The upshot of which is that I need some 20 AWG 600V rated PTFE hookup wire, ideally silver ...
by Thermionic Idler
Sun Jan 05, 2025 1:58 pm
Forum: Suppliers, recommended or not
Topic: Primary Windings
Replies: 5
Views: 25388

Re: Primary Windings

Well, over Xmas I ordered 4 mains transformers and 2 chokes - still awaiting their delivery but it's the holiday season so fair enough. The products look good value although I wish they would post more technical data that would allow more accurate PSUD predictions.
by Thermionic Idler
Mon Dec 30, 2024 2:58 pm
Forum: Beginners
Topic: HT and filament heating from the same transformer
Replies: 7
Views: 17875

HT and filament heating from the same transformer

One thing Lynn Olson recommends is to have filament transformers be separate from the HT transformer, at least for DHT's like 300B's. This is because you (apparently) get rectification switch-noise from the HT secondary winding capacitively coupling into the low-voltage filament circuit.

When I ...
by Thermionic Idler
Sun Dec 29, 2024 7:15 pm
Forum: Buying and Selling
Topic: Hammond 193B Chokes x 2
Replies: 11
Views: 8719

Re: Hammond 193B Chokes x 2

Paul Barker wrote: Sun Dec 29, 2024 2:35 pm The tdk caps and sovtek 2a3 are interest to me. I have enough ecc81 ECC88 and 6v6.
OK, I need to look up what I paid for the TDK caps originally so I can get an idea of what they are worth (if anything). I'll do that and get back to you.
by Thermionic Idler
Sun Dec 29, 2024 12:23 pm
Forum: Buying and Selling
Topic: Hammond 193B Chokes x 2
Replies: 11
Views: 8719

Re: Hammond 193B Chokes x 2

Interesting! :D That's a nice stash of KT88 / 6550's you have there, but as you say, in exchange for two Hammond chokes - not gonna happen for even one, let alone four, that wouldn't be a fair ask.

The D3a's are probably the most realistic swap. I'm looking through my own valve stash to see if ...
by Thermionic Idler
Sat Dec 28, 2024 3:12 pm
Forum: Buying and Selling
Topic: Hammond 193B Chokes x 2
Replies: 11
Views: 8719

Re: Hammond 193B Chokes x 2


Are there any valves you want we could swap? I can’t buy anything at the moment.


Well, total requirement across the two Redwing monoblocks will be 2 x 12SN7, 4 x KT88 (matched pairs), 4 x 300B's, 4 x 0C3 / VR105 regs.

I don't have any KT88's or 0C3's yet (though I know for any KT88's I'd have ...
by Thermionic Idler
Sat Dec 28, 2024 12:12 pm
Forum: Buying and Selling
Topic: Hammond 193B Chokes x 2
Replies: 11
Views: 8719

Hammond 193B Chokes x 2

Another item liberated by Project Redwing - 100mA is insufficient for 2 KT88's and a 12SN7 so these are up for grabs.

https://www.hammfg.com/part/193B

£40 each or will let them go as a pair for £70.

Coming soon, a bunch of TDK motor run caps...
by Thermionic Idler
Fri Dec 27, 2024 7:40 pm
Forum: Buying and Selling
Topic: Hammond 400-0-400 HT Transformers
Replies: 6
Views: 15798

Re: Hammond 400-0-400 HT Transformers

I'll be ordering them imminently - Primary Windings https://primarywindings.com/product/pwht04-300v-320ma-6-3v-3a/ the frame version will allow me to attach the power supply PCB's vertically. At that rating they should run nice and cool.

EDIT - two of the chokes will be for sale too, will list ...