Simplistic NJFET RIAA

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Joined 2009
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Merlin,

here is another candidate (maybe?)
Digi-Key - 490-1957-ND (Manufacturer - TZ03R121F169B00)
It's good to have some small fixed value caps on hand when you do that.

Hey psgr,

I am glad to hear you again, that's you propose it's ceramic but if you use only to finetuning the RIAA can be OK if when you know the exact value replace for fixed better caps.

Do you have photos of your RIAA & regs.?

Cheers

Felipe
 
Merlin,
I have not started yet, I'm missing a few parts. Now that it started getting cold and I will be spending more time indoors I will complete the Riaa.

About those variable caps your working range is 180 degrees, maybe it's better if you can find something with a little larger capacitance, it might be easier to work with.
 
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Joined 2002
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Giasou Salas,
I saw that the other day, I will.
I have a MM cart of unknown brand, since there is no label on it, I'm not sure what is the output !!!
I have not heard from you for a while, did you get version a3 of the document?

Pete

Just looked by email search and its there indeed. I don't remember reading it though. Must have skipped it. Will read it and let you know.

Make the R2=100R MM, its most possibly a normal MM cart.
 
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I have been experimenting with decoupling caps in my 48dB riaa and I am amazed by the results.... these caps influence tone (I knew that) but they also influence noise...

After replacing the 330u decoupling caps by 680u BG N, the noise went down to the point where I can no longer hear it..... Is it possible or is there any other reason ?
 
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I have been experimenting with decoupling caps in my 48dB riaa and I am amazed by the results.... these caps influence tone (I knew that) but they also influence noise...

After replacing the 330u decoupling caps by 680u BG N, the noise went down to the point where I can no longer hear it..... Is it possible or is there any other reason ?


330uF was also BG with same voltage?

BG are my prefered lytic caps, I love them, are far better that any cap, it is a shame that is stopped making.

Also are killer in PSU.

Welcome to the BG no noise:D
 
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Look at the red ones on the riaa boards.

The difference is UGE in noise floor.

Can we have an alternative to those decouplers ? Maybe another type of decoupling or RC filter that does not need special caps....:D
 

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Member
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Look at the red ones on the riaa boards.

The difference is UGE in noise floor.

Can we have an alternative to those decouplers ? Maybe another type of decoupling or RC filter that does not need special caps....:D


Ricardo you you have two possibilities depending what are you looking for:

1-Less noise can reached paralleling two BG N "L-Cancelling Pairs" so + one cap to - other cap, look for at the Michael Percy pdf. web

2-N series are very very low noise so very very transparents, if you like more body I will try BG standard 470uF 160V you will be near near heaven:)

Let me know?