M77 build

I have found JMS inexpensive, responsive and reliable, unlike…

forgot about the 13V winding.

M77 uses a pair of mains tx, each is:

200 - 0 - 200V @ 30mA
6.3V @ 1A
13V @ 2A

the 6X4 is used in a hybrid bridge

Is there a technical argument against using separate Tx for each o/p voltage?

Obviously aware of the cost argument, but no intention of productionising.

FTFY :grinning:

The Nobsound pcb doesn’t use a hybrid bridge iirc

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I’m currently using a separate transformer for the 12V winding. No issue with it.

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argument is generally in favour of separate tx, as reverse diode pulses from heater supply will be isolated from HT supply.

Rod Coleman regularly recommends JMS for his filament supplies as they do nice split bobbin designs, and will add electrostatic screens inside and copper band outside, all which help to minimise noise, which is nice

Mine’s gonna be all-toroidal.

Canterbury Windings ?

VB

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So far the ebay seller continues to take the piss - currently wants £60 for a PCB, even with a group buy!

Offered £25/ea, if they don’t get close, the PCB buy is DOA.

Buy one, get it copied here for a more reasonable price, spread the cost of the expensive one over resales to your mates.

VB

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Love the irony of playing the Cinese copyists at their own game.:grin:

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This forum, it’s a race to the bottom. Unsurprising, wth @Penance as a mod…

Just ask the seller to send a full photocopy of the board and don’t buy one at all.

I’ve got a spare blank board if someone does want to get one copied. But I’ll want it back when done!

Actually I still think this is a good deal.

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Get a few membrs of the forum on to this and we could have a new splinter group.

The Nobbo Mafia

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The price of the populated boards is fine, but I have, let’s say, trust issues with a company who’s openly ripping-off someone else’s design and their component quality… Could, of course, be fine, but then what are the chances that the phono section is well matched and closely toleranced…?

Only wanted PCB because I’m lazy and didn’t fancy home-knitted…

Nobdo, surely?

It’s win win all the way.

I’ll take a wild guess and suggest that it might just be slightly inferior to Audio Note Japan. However, the kit that Guy bought and built seems good enough for starters.

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Good enough is not good enough.

One is £350, the other is >100x that!

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Is this dead in the water?