Hey Pete, how's it going? 🙂
I bought some around this time last year (25 of each I think) and they were not that much then. Looking at Digikey now, these are $2.32 (here)! Maybe worth it though if you don't use 10 of each in a design.
I think it was on a tip from you that I bought them.
I haven't had a chance to test drive them yet.
I managed to get 3601 at a sensible UK price.
I gave up trying to find 1407 at a price I was prepared to pay.
I gave up trying to find 1407 at a price I was prepared to pay.
PNP complement KSA1381
last time I checked both of these are ~ $0.25 ea
I have found the mje340 works well for me.
In combination with a CCS using MJE350.
You realy dont need loads of gain as this then needs slugging with a CB capacitor to stop oscillation.
In combination with a CCS using MJE350.
You realy dont need loads of gain as this then needs slugging with a CB capacitor to stop oscillation.
Usually the VAS is the dominate voltage gain stage😉 so high betas are good, and normally a cap from CB is used here for the amps overall feedback compensation cap. Besides you want an external capacitor here to help swamp the device parasitics for linearity and stability with a large voltage swing. Most conventional 3 stage power opamp topologies can use lots of beta here for high OLG ie negative feedback. Do you use more stages or something else.
My LTP has a current mirror to up the gain.
This saves having to have so much gain in the VAS.
The thing I dislike about using 340/350 is that quite a few parameters are not specified and with so many vendor sources, I'm not sure what I'll get.
What about an additional cap from VAS collector-base or do you depend on the Cob of MJE340?
Hey Pete, how's it going? 🙂
I bought some around this time last year (25 of each I think) and they were not that much then. Looking at Digikey now, these are $2.32 (here)! Maybe worth it though if you don't use 10 of each in a design.
I think it was on a tip from you that I bought them.
I haven't had a chance to test drive them yet.
Longggg time , no see , I am M.O.A.N- ing hard core now.. 😀
Yes , lots and lots of gain... with KSA/C's + beta enhancement = 100DB , and Nico RAS's inspired design BOTH a current mirror and a beta enhanced VAS (symasym style) = 135db+ (too much - especially with the Ksa1381). If you use the old MJE340/50's with one of these these "gain monsters" (pix1 - 105db) AND add a touch of "spice" (TMC), you get some real sound 🙂 - (pix2) The MJE's Higher Cob/lower beta actually makes some designs (especially the one in pix1 @ 80db- w/mje340) , sound better by moderating the loop gain.
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Great to hear and good to see you back as well. 🙂
Looks like you have a few things brewing.😎
I'm not up to speed yet but I have a few ideas that I'd like to get going on.
Salas,
as far as I know Samsung owns Korea Semiconductor Company (KSC) and Samsung Electronics Corporation (SEC), anyway, semiconductors manufactured under license does not necessarily exhibit nearly identical characteristics to those of the original item.
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The MJE340/350 was not intended for voltage amplification but for switching.
Video transistors were developed for CRT screens and presumably will be available for a limited time.
Can anyone point me to a reliable source for Sanyo 2SC3600 / 2SA1406 please?
as far as I know Samsung owns Korea Semiconductor Company (KSC) and Samsung Electronics Corporation (SEC), anyway, semiconductors manufactured under license does not necessarily exhibit nearly identical characteristics to those of the original item.
¤
The MJE340/350 was not intended for voltage amplification but for switching.
Video transistors were developed for CRT screens and presumably will be available for a limited time.
Can anyone point me to a reliable source for Sanyo 2SC3600 / 2SA1406 please?
You have been gone awhile ... your "patchwork" = "blame ES" = my BX. Your patchwork was a great inspiration for a great amp. On "steroids" (TMC + VAS beta enhancement ) , it can be a good PPM / near perfect amp. 🙂 I'd LOVE to have a couple 2SA1407's to plug into it.
Check dis' out ..(Below 1/2- no lie) Works and works GOOD...
OS
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