Interesting Vfet cascoded by vfet what be happen ?
Behaving like a tetrode
Not if you choose well your Vbias, I believe...the sweet spot, so to speak.
Cool ! Powerful SIT's with high gain are back in stock from verified Japan shop.
watanabetomoaki | eBay
Make offer and have a good price
watanabetomoaki | eBay
Make offer and have a good price
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Hi guys,
Anyone can share their projects on this wonderful SIT?
SIT with low thermal memory input.
Second one is not proven yet.
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Hi Christophe, Watanabe-san also sell MRF255, high power Lateral RF mosfet with isolated case like the pucks, gm comparable to IRFP250 and parasitic capacitances comparable to IRF510. Seems suitable for Mofo at 19V and 2.5A
Yes but MRF255 datasheet show is 55 watt´s max power
MRF255
https://www.mouser.com/datasheet/2/427/91212-102915.pdf
What about Tokin SIT depletion mode Big MoFo version haha ?
Have a nice day
MRF255
https://www.mouser.com/datasheet/2/427/91212-102915.pdf
What about Tokin SIT depletion mode Big MoFo version haha ?
Have a nice day
Correct, maximum usable power output. Max device dissipation 175W, 1 W/K derating and 1 K/W Rtjc. No forseeable problem for 19V supply and 2.5A bias. 24V supply will hit Vdss.
A SIT follower is of course uber nice. An inducted SIT3, ... a SitFo. The caretaker of opldf will be restless.
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Not yet, same boat situation with opldf caretaker.
Member Vladimir bult a modified power follower 99 with an RD100HHF1 in this thread. MRF255 and MRF151 are better suited for MoFo due to isolated flange allowing direct metal to metal contact to the heatsink for better thermal transfer.
Of course an inducted SitFo or L'amp is a bit more interesting.
RD15HVF1 also looks good for cascoded common source, common TO220 with flange connected to source so can be mounted without isolation to heatsink when no source resistor is used. A bit less gm compared to the IRFP240 with negative tempco for Id > 1.7A. Much better choice in terms of greenies and commonly available in Europe like Naltronic.
SIT in the MoFo way
I have two copies of sk180 that gave me jama. The aim was to experiment the SIT in the configuration of L'Amp by Mr. Rotacher that fascinated me. However, in the meantime I built the Mofo with the IRFP250 mosfet which is giving me enormous satisfaction. For some time I'm wondering if to use the sk180 instead of the irfp250 can make it possible a further step forward in the current performance of my Mofo in the same configuration. I am also aware that a buffer is necessary to properly control the gate (due to its high capacity). have you experimented in this sense? And above all it makes sense as a Power Buffer?
I have two copies of sk180 that gave me jama. The aim was to experiment the SIT in the configuration of L'Amp by Mr. Rotacher that fascinated me. However, in the meantime I built the Mofo with the IRFP250 mosfet which is giving me enormous satisfaction. For some time I'm wondering if to use the sk180 instead of the irfp250 can make it possible a further step forward in the current performance of my Mofo in the same configuration. I am also aware that a buffer is necessary to properly control the gate (due to its high capacity). have you experimented in this sense? And above all it makes sense as a Power Buffer?
All I know is Mr Rothacher MoFo designer & expert and his future SIT amp.
Guess Diyers can possibly build MuFo MoFo another version with more power and high gain Tokin's.
Information source: AudioMaker | DIY Audio Projects & More Thanks to AudioMaker!
Guess Diyers can possibly build MuFo MoFo another version with more power and high gain Tokin's.
Information source: AudioMaker | DIY Audio Projects & More Thanks to AudioMaker!
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Or find cheap skate cascoding transistors equivalents from Mickey Mouser
Mouser Electronics Europe - Electronic Components Distributor
The important parameter for large capacitance big SIT amp is a good match with preamplifier
who have low ~ 25 Ohm impedance that is perfect for this purpose.
If the active preamplifier output impedance is high we can get a better frequency bandwidth response
if the use of B1 passive jfet buffer between preamp and amp , who can do all nice job.
See what Papa says is starting at 0:20:02
2015 Burning Amp Speaker: Nelson Pass