L'Amp: A simple SIT Amp

juanitox probabily yes , if Tamura have normal iron and amorphous iron for psu choke.....DhtRob on choke test confirm this ,forum user too, how I dont know!! probabily as on air the Michael choke don't have this problem...btw the resistence is higth....

you can open up the clarity caps with small mundorf s/o

PS I vote for grid choke :D
 
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Pass DIY Apprentice
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do you think your hand made inductors will sounds different than the Hammond too ? :)

It does sound a bit different. I think the big coil retains much of the liveliness and triodey richness of the light bulb version, whereas the iron choke and CCS versions begin to sound slightly more conventional to my ears (and with my speakers)

They're all good, but if I had to choose, the big dumb coil remains my favorite for now. :)

I haven't yet experimented with different caps. I hear those Clarity caps impart lots of ooey-gooey goodness.
 
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@Salas
The series strap button works pretty well, no major issues. I think there's a big relay circuit involved, and sometimes it takes a couple of presses to latch up.

Ah, the Edsyn, that's my lucky iron. I love it. :)

Don't know if it will handle it in case of short, but you are in no production line to be so eventful anyway. Having the current knobs fully right?
 
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Yes, fully right.

I think you're right about the series relay handling a short, probably better to use a heavy wire to connect them in a more permanent installation.

They have been pretty robust though, and have survived a couple of dumb mistakes in the lab.

The supplies supplies pictured are the 50V X2, so I could try those 100V DeLites. :)
 
Maybe a bit OT, maybe not given this kind of amp's power supply range. There are $200 double and $130 single linear high current regulated bench supplies about. I have a double 30V 5A unit for series linking up to 60V high or up to +/-30V symmetric. Also because I could find one of the fan-less variety in doubles. Maybe good for checking out such amps fast, listening, and then deciding to keep and build them their own costly supplies. And for a number of other projects of course. For Matching MOSFETS, SiC JFETS, SITS, also. But don't use it as a circuit's CCS, you remember it did not work correctly for member Protos amp. It takes to fit an NTC primary side not to trip 10A breakers (I put one there). That trafo is 500VA easily. Construction is so-so, but OK for the price. Its meters look set true. Setting the scope's trigger for single shot, I captured the power on event. Looks smooth, no over voltage or ringing. That one's a 5V/Div 100mS/Div ramp up.
I was looking at those recently. I always felt slightly challenged with single linear supply.What is the best source to buy from?
 
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Please excuse my lack of transistor knowledge here. Is bias the same as Id (indicated by the arrow) and determined by the setting of P1?

Regards,
Dan :)

completeschemptone.jpg
 
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I was looking at those recently. I always felt slightly challenged with single linear supply.What is the best source to buy from?

If you mean in Greece, there are enough on line local retailers with good for European standards price (~220 for the 5 Amp ones) if you will google the brand name + type choosing to show Greek results only. Best prices in general are in USA especially when factoring in $<EUR.
 
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Please excuse my lack of transistor knowledge here. Is bias the same as Id (indicated by the arrow) and determined by the setting of P1?

Regards,
Dan :)

completeschemptone.jpg

Yes, sounds like you've got the idea.

Id is controlled by the voltage between the Gate and Source pins. Here, P1 adjusts this voltage. Id is temperature dependent and will need to be adjusted initially, and again after an hour, once things have equalized.
 
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Yes, sounds like you've got the idea.

Id is controlled by the voltage between the Gate and Source pins. Here, P1 adjusts this voltage. Id is temperature dependent and will need to be adjusted initially, and again after an hour, once things have equalized.

Michael,

Thanks for your response. After some searching I finally found a novice-friendly description of JFet biasing.

Regards,
Dan :)

FET biasing - Electronic Circuits and Diagram-Electronics Projects and Design

fixed-bias-circuit-for-jfet.jpg