The Exicon MOSFETs are laterals, inappropriate for the Slewmaster OPS. Post 9498 of this thread has a list of appropriate bipolars for this design.
The Slewmaster OPS was originally designed only for bipolar transistors, it was later found that it was a simple modification to allow the use of vertical MOSFETs. This option was then integrated into the latest version of the PCB.
If yow want a OPS that uses laterals, Search the Slewmaster threads for the "Mini OPS".
The Slewmaster OPS was originally designed only for bipolar transistors, it was later found that it was a simple modification to allow the use of vertical MOSFETs. This option was then integrated into the latest version of the PCB.
If yow want a OPS that uses laterals, Search the Slewmaster threads for the "Mini OPS".
Newark puts the Sanken MT200 devices on sale regularly. I picked up 50 for $1.50 each last sale.
Thanks guys, I guess I had read something regarding the mini-OPS and assumed the same applied to the larger version. Will stick with the Sanken MT200.
Will be checking newark for sure on the $1.50 a piece pricing...awesome deal.
Will be checking newark for sure on the $1.50 a piece pricing...awesome deal.
Spooky V2 Question
Has Pete or anyone built Spooky V2 with real parts and tested it on a bench with the OPS boards? Pete told me to wait about a year ago. Just checking. Thanks, Ray
Has Pete or anyone built Spooky V2 with real parts and tested it on a bench with the OPS boards? Pete told me to wait about a year ago. Just checking. Thanks, Ray
I am now building my second Slewmaster, this time with the Spooky IP (Jkuetemanns layout). I have two questions and hope for repons.
OPS: C102/105 are listed to be 22uF100V. I have 22uF/35 V (also 100uF/100V but they do not fit so well). Can I use this? (powering will be around 70-80V DC).
IPS:
Farnell coud not deliver KSC 1815. I have plenty of BC 550/560. Can I use BC550 for Q1/2 and still keep Q3 -Q8 as listed in the BOM-list. They are already soldered. Or will this changes I want to do with Q1/2 also results that I must go for BC 560 as well?
Eivind S
OPS: C102/105 are listed to be 22uF100V. I have 22uF/35 V (also 100uF/100V but they do not fit so well). Can I use this? (powering will be around 70-80V DC).
IPS:
Farnell coud not deliver KSC 1815. I have plenty of BC 550/560. Can I use BC550 for Q1/2 and still keep Q3 -Q8 as listed in the BOM-list. They are already soldered. Or will this changes I want to do with Q1/2 also results that I must go for BC 560 as well?
Eivind S
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To me honest I am not sure, but I have studied post 9498 here: http://www.diyaudio.com/forums/solid-state/248105-slewmaster-cfa-vs-vfa-rumble-950.html.
I have followed Jkuetermans BOM list to his pcb for Spooky. What schematics he has taken into his lay out, I dont know.
Eivind S
I have followed Jkuetermans BOM list to his pcb for Spooky. What schematics he has taken into his lay out, I dont know.
Eivind S
I think vi must have Jkuetermann "on the field" to hear what his has to say about this question(schematics)
Eivind S
Eivind S
R33, the NFB lower leg, is shown connected to the power ground at the bottom of R3.
It should be connected to the Signal Return at the bottom of R2.
There was some discussion about the servo in this series of amplifiers. Not sure which one.
The servo feed to the -IN node is via R36. This is 15k to match R32.
Usually the servo resistor is about 5times to 10times the feedback upper leg resistor. i.e. R36 could be 75k to 150k. I'm not sure how that previous discussion ended.
It should be connected to the Signal Return at the bottom of R2.
There was some discussion about the servo in this series of amplifiers. Not sure which one.
The servo feed to the -IN node is via R36. This is 15k to match R32.
Usually the servo resistor is about 5times to 10times the feedback upper leg resistor. i.e. R36 could be 75k to 150k. I'm not sure how that previous discussion ended.
The different transistors in the upper and lower LTPs will probably result in higher distortions than if they were good complements. I don't know how much that will affect the outcome.
But no transistors are perfect complements, so maybe small errors will be reduced sufficiently by the NFB that any change will be inaudible.
Try at least to get similar hFE, so that the base currents are near cancelling.
I can't find the caps C102 C105.
But no transistors are perfect complements, so maybe small errors will be reduced sufficiently by the NFB that any change will be inaudible.
Try at least to get similar hFE, so that the base currents are near cancelling.
I can't find the caps C102 C105.
Andrew I think you have put post 1953 in the wrong thread. I think the mistake has somethings to do with my question on grounding F5V2 in another thread.
Eivind S
Eivind S
I clicked on your link and it came back with a Spooky-V1.2 -schematic.
I read that and gave my comments thinking that was what you were asking about.
I read that and gave my comments thinking that was what you were asking about.
It's difficult to comment on OPS if I don't see the exact schematic.
OK, I've found it. C102/C105 will see almost the full rails voltage, so "no go" for 35V rating. It has to be 100V.
BC550/560 in place of KC1815/A1015 will be fine, assuming they run at Ic < 10mA in this particular case. BC550/560 start "feeling bad" at higher currents (hFE droop).
Cheers,
Valery
Gooday all,
Can someone plse post the latest schematic and BOM of the Kypton ND.🙂
Will be appreciated !
Can someone plse post the latest schematic and BOM of the Kypton ND.🙂
Will be appreciated !