That is smoked. Wonder when this happened. Like this it will smell a bit and you will also notice some real smoke.
As ZM writes it is important to also check all resistors for correct value.
If some resistors are mis-colored then also change those.
If you are not experienced in pulling parts it can be a mess. Maybe better to cut legs and pull out legs after legs and buy new parts (but not the expensive JFETs of course). Maybe let them sit? ......but ZM said pull all actives 😳
As ZM writes it is important to also check all resistors for correct value.
If some resistors are mis-colored then also change those.
If you are not experienced in pulling parts it can be a mess. Maybe better to cut legs and pull out legs after legs and buy new parts (but not the expensive JFETs of course). Maybe let them sit? ......but ZM said pull all actives 😳
Since we have mentioned fuses, what size/amp fuse would be suitable for this unit at 120 VAC? Yes, fuse on hot wire and before power switch.
I reckon JFets didn't even get voltage, so - if soldered correctly and not misplaced, same as bjts around them, no reason to touch those
(VA of your Donut)/(mains voltage in your neck of wood)
then take closest standard value, up or down, whatever, slow-blow or T(rage)
It depends on the transformer you use (how much it "kicks" during startup / inrush current). Toriods usually "kicks" more. I used a 20VA Toroidy transformer. The Toroidy company specs. 160 - 180 mA T for that transformer. This is for a 230 VAC type. Then for 120 VAC then maybe just double up.
You can also do as ZM says. Try that and if it blows during startup use the next standard value. Then for a 20 VA / 120 VAC it will be 180 mA T. If it blows go for a 0.2A T or 0.25A T.
I must be some kind of ocd that makes completing such things so rewarding…even before knowing if it works 🙂
The case has made it to the states, but saying 4 more days to get here.
The case has made it to the states, but saying 4 more days to get here.
I am pretty much in the same boat. New panel may come tomm. Even then there is much to be done. I am in a position of building another unit, but that is way out there. Despite that fact, parts for the second unit are slowly arriving.
I never really planned on any of this, but as you will soon find out, it is head and shoulders above just about anything that I have ever heard.
I never really planned on any of this, but as you will soon find out, it is head and shoulders above just about anything that I have ever heard.
Ill give those legs a trim 😛. Finishing up after feeding the fam, logic too. I neglected to order LEDs so also have to rummage for spares, and liberate an additional volume pot from another pre to have a pair. Debating mounting everything to a piece of lumber until the case gets here.
I am VERY much excited to hear this with the M2X. I built a DCB1 years ago and distinctly remember being floored by the detail, but the amps it fed were sterile to my ears. I let it go to a new home ( and the commercial amps it fed ) when I built the F4 and a BA3-FE. Not enough cash at the time to retain all.
It was also an imortant lesson in what my ears like.
Thank you for all your help ZM! As always, and over the years 🙂
I am VERY much excited to hear this with the M2X. I built a DCB1 years ago and distinctly remember being floored by the detail, but the amps it fed were sterile to my ears. I let it go to a new home ( and the commercial amps it fed ) when I built the F4 and a BA3-FE. Not enough cash at the time to retain all.
It was also an imortant lesson in what my ears like.
Thank you for all your help ZM! As always, and over the years 🙂
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I'm looking for the "best" filtered power module for the the Modushop chassis. I see that Schurter DD12.9111.111 was recommended. This is a 10A unit, but the Iron Pre obviously doesn't need all of it. According to the spec sheet, the 1, 2, 4, 6, 8, and 10A all use different value caps. They are all about the same price, so there must be a reason why they make them in different "strengths". What is the benefit of using a module that more closely matches the power draw?
I also have a question about the Power LED power source. Is it possible to tap into the LED resistor on the Twister Board? That way it'd use the same source for all the LEDs. Where would be the best place to attach the return? I'm having trouble figuring out where the common return is. Would that be pins 13/14?
I also have a question about the Power LED power source. Is it possible to tap into the LED resistor on the Twister Board? That way it'd use the same source for all the LEDs. Where would be the best place to attach the return? I'm having trouble figuring out where the common return is. Would that be pins 13/14?
it'll work if you don't use any of Twister LEDs, so LED resistor feeding just your permanent one
if you're using twister and its LEDs, then you need dedicated resistor for your permanent LED, but - I reckon, in that case you'll not need permanent LED
