Mosfet amplifiers including Susan Parker Zeus amplifer

[nige2000]

ives soldered usm packages before
the trafo will be more of an issue, id have to order parts from aliexpress which usually take a month,
then there's all the parts variations wire sizes and bobbin sizes.
i imagine id end up with a trafo factory for options if i go that way,

right.. whats the trafo shopping list ill get em ordered

[abraxalito]

You don't need the trafo - that's taken care of with the transistor gain stage. I'd check to make sure the input FETs are available on Mouser/Digikey.

The power supply I shall get installed shortly, a MeanWell brick I think will be suitable, 24V and 4A. Filtering probably will be needed though - that's where the trafos work their magic in mitigating the supply noise.

[nige2000]

What's the input fet

[abraxalito]

SSM3K35FS - can't find that in the regular suppliers. They have 3K35MFV though, same die just 75% of the size (1.2mm long).

[jkeny]

SSM3K37FS is available in Mouser - same size as SSM3K35FS but 12pF Ciss Vs 9.5pF
lower o/p capacitance 5.5pF Vs 9.5pF (35FS)
Any use?

[nige2000]

thats pretty small ill have to get a few extra for the floors cut
anything else i need to get in mouser

[abraxalito]

Its only a few pF more Crss than the K35 so yeah I think it'll be fine. Yfs curves look almost identical.

The other FETs I'm using are K339s which I think John already has.

[nige2000]

already ordered the k339 and the j327 ? a while back

[abraxalito]

The other semis are BC846B and BC856B which I use for current sources and current mirror. Caps are 10uF 35V TDK X7R (or X5R) 1206 for decoupling and 100nF NPO for coupling. Plus TDK 7mm inductors for PSU filtering (150uH SLF7045). Then some low ESR electrolytics for damping on the supplies.

[nige2000]

rs components had 110 x SSM3K35FS a few minutes ago ( as in past tense )