Bigbottle MM/MC Hybrid Valve Phonostage PCB

[Bigman80]

I have these....I'll try them

 

[smangus]

Interesting, I have some of those spare, idss is abot 10 though so not high enough by the sound of it.

 

[Flikoman]

I have these....I'll try themView attachment 831469

You said low Idss ... I don't know the schematic, but maybe you'll have to change Rs value for lower Idss device.

 

[Bigman80]

You said low Idss ... I don't know the schematic, but maybe you'll have to change Rs value for lower Idss device.

I said same IDSS as thebones in the BOM but there is no harm I seeing what happens with the aforementioned fets

 

[Flikoman]

I said same IDSS as thebones in the BOM but there is no harm I seeing what happens with the aforementioned fets

Can you post the latest BOM in the first post, please? 😉

 

[Bigman80]

This is the very latest one:

BOM MM-MC - Google Sheets

 

[craigtone]

Yes, unless someone finds a through hole version that is better?

If you can find 2sk170c then you could manipulate the legs to fit.

Hence my search to experiment but it seems this version wasnt as popular.

As long as gate is the center pin source and drain don't matter on a JFET.

 

[Bigman80]

As long as gate is the center pin source and drain don't matter on a JFET.

Ah, thanks craig.

Any input on the use of alternatives for the BF861C?

 

[Marra]

It seems that I am running true to form and have missed one of the resistor from my Farnell order. Does any one have some 3k3's they could post to me please and a couple of red LED's.

 

[craigtone]

Ah, thanks craig.

Any input on the use of alternatives for the BF861C?

Not really ... getting close to the Idss of the BF861/BF862 is the key.

 

[Bigman80]

Not really ... getting close to the Idss of the BF861/BF862 is the key.

Yup, I see

 

[elnaf]

Just curious what the measurement of the pcb is. I have som different enclosures and my head spin on which one to choose

 

[brommermartin]

It's arrived. Top Quality board !

 

[mhenschel]

Just curious what the measurement of the pcb is. I have som different enclosures and my head spin on which one to choose

According to an earlier post: 90 x 245mm


(I remembered seeing it in a post and tried a search for this but came up with nothing. So I did a brute force search...'cause I hadn't made a note!)

 

[Marra]

All my red led's give a reading round about 1.724 volts; is this ok?

 

[elnaf]

According to an earlier post: 90 x 245mm


(I remembered seeing it in a post and tried a search for this but came up with nothing. So I did a brute force search...'cause I hadn't made a note!)

Thanks

 

[ikir]

US based folks, what transformer are you planning to use for the build?

 

[Flikoman]

PCBs arrived. They look awesome.

 

[sasha70]

Thank you Oliver, I have received PCB.
Fantastic quality.
Could you please advice on transformer?
Best regards.
Sasha.

 

[entropist]

US based folks, what transformer are you planning to use for the build?

I picked up the Chinese manufactured R-core mentioned earlier in the thread (R26-90); took 5 weeks arrive, but it's here now!