I have a trial PCB at 3V3 on the bench, full smd for space saving.
Regarding 2SK880s, i am now testing it with 2mA Idss of the Y classification without source resistors
If I use the GR classification with a source resistor to reach the 2mA, in what will differ?
Morning.
I suspect my lack of knowledge prevents me from being assured that the things I do I do right 🙂
It is embarrassing but I ll give a go.
15 V from the psu. G,S pins shorted. Meter in ma range, I put one lead on the V+ and another on the drain- measurements bunched around 8-9ma.
Am I doing it right?
I suspect my lack of knowledge prevents me from being assured that the things I do I do right 🙂
It is embarrassing but I ll give a go.
15 V from the psu. G,S pins shorted. Meter in ma range, I put one lead on the V+ and another on the drain- measurements bunched around 8-9ma.
Am I doing it right?
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Hi Salas,
Could you please share your thoughts about using wirewound non inductive vs metal film low noise resistors (paralleled for appropriate wattage) for the CCs R1 position.
I have used the Vishay MBB series in some of my 1.3 builds and wirewound Vishay RS in others. Not very sure which I prefer since my A/B experience is limited. I am presently building a set of 1.3 for use with the Soekris dam2941 and I thought that since its been almost six years since the 1.3 were introduced, your sonic experience might suggest a preference for one type over the other in a specific type of application.
Thank you. Nash
Could you please share your thoughts about using wirewound non inductive vs metal film low noise resistors (paralleled for appropriate wattage) for the CCs R1 position.
I have used the Vishay MBB series in some of my 1.3 builds and wirewound Vishay RS in others. Not very sure which I prefer since my A/B experience is limited. I am presently building a set of 1.3 for use with the Soekris dam2941 and I thought that since its been almost six years since the 1.3 were introduced, your sonic experience might suggest a preference for one type over the other in a specific type of application.
Thank you. Nash
Low inductance are also the thick film TO case types that many 1.1. & 1.3 users subjectively like. You could try one for yourself.
example: https://www.bourns.com/docs/Product-Datasheets/PWR220T-35.pdf
example: https://www.bourns.com/docs/Product-Datasheets/PWR220T-35.pdf
I forgot to order Rf so connected bench psu to C1 to test.
Target output is 5V so my 3296Y-1-502LF positive trimpot is fine but negative side is just above -5.22V and stops there.
Should I order a different trimpot or there is a way to adjust Rvv or similar to fine tune dc?
Thanks
Target output is 5V so my 3296Y-1-502LF positive trimpot is fine but negative side is just above -5.22V and stops there.
Should I order a different trimpot or there is a way to adjust Rvv or similar to fine tune dc?
Thanks
I know. Did not have any. Might order a bunch extra to match or use ubib with 15v build I am planning.
Jumper short one LED at its pads underneath to free some downwards voltage space for the trimmer.
Correct. But for another reason i.e. stiffer local CCS for Q4 since available Vds vs Vgs is insufficient over J3 when set at 5V out. Smaller IDSS samples do have smaller Vgs (OFF) too. So they nest better. J3 is not an integral part of the Vref branch.
Thanks, it worked. However I used my stock of leds and positive side is red, negative is green hence the overshot? If I change neg side to red leds it should work then.
It is. Replaced a jumper with one red and it went below but not enough. Going to look for another red, might find if lucky 😄
As a recent example, see Stajo's build post #3,973 where a Caddock thick film R1 is prominent in the photo
I repost in case it got lost between others
Regarding source resistor
Does it somehow serve like it works better in the linear region than in saturation?