...just checked and my request to purchase some signal transfer PCBs goes back to Feb 2020! Back then i got a reply (from Gareth) to say they were available but then radio silence. Obviously now lost in the mists of time so I will go to the ST site and try again. I note the forgoing not to rub salt into wounds but to reflect that it's a sad outcome as Gareth had previously been very helpful on some detailed matters regarding the pre amp kit I purchased some time before 2020.
DRC: Design Rule Check
You can set rules when designing - like minimum clearance between traces, pads, outlines, etc. DRC checks to ensure you've complied with these rules. They are often set from a electrical functionality perspective.
DFM: Design for Manufacturability
This is the PCB fabrication house rules. They will also have minimum and maximum specs they can manufacture to. Like minimum silk screen sizes, clearance to board outlines, via sizes, etc.
There's additional checks such as:
DFF: Design for fabrication. This ensure it can also be fabricated, if using an assembly service.
You can set rules when designing - like minimum clearance between traces, pads, outlines, etc. DRC checks to ensure you've complied with these rules. They are often set from a electrical functionality perspective.
DFM: Design for Manufacturability
This is the PCB fabrication house rules. They will also have minimum and maximum specs they can manufacture to. Like minimum silk screen sizes, clearance to board outlines, via sizes, etc.
There's additional checks such as:
DFF: Design for fabrication. This ensure it can also be fabricated, if using an assembly service.
Yes. If you have very much difference copper areas on different parts of the board, you can get over- or underplating. If that is flagged, you can place some copper in some areas to balance the distribution.
The attached is a well-balanced board, as you can see with the color bar at the bottom. Slight overplating at the left side, but nothing to worry about.
Jan
The attached is a well-balanced board, as you can see with the color bar at the bottom. Slight overplating at the left side, but nothing to worry about.
Jan
Attachments
PrecisionPreamp
Never really talked of my works... but first thanks to m.Self for my audio inspiration. Unfortunately on this thread I'm not a buyer of the Transfer Company but I do agree that after reading products of the site they're of very good quality. Neather a buyer of CarlHuff's products but I only have good words on a product that really brought me to a top-level of audio listening.
To keep short:
My PCBs are made in China and the quality is stunning. And the price is 1/3 of North America's price. Delivery is very fast. Again I insist in having a good ground plane on top PCB and most of tracks on bottom side. Also voltage distribution should be made in the state-of-the-art. Fault finding must belong to the board designer.
Every low-level signal equipments have the main supply outside of boxes in my version, limiting 50-60Hz getting inside preamplifier.
My amplifiers consist of the Load Invariant of m.Self. Some works had to be done in the output stage and 130W/channel has been possible using +/- 50V supply and all Toshiba transistors inside.
Aside technical facts, only the listening help justifying the work and now I know!
Thanks m.Self for the reading on audio made available from your works.
Never really talked of my works... but first thanks to m.Self for my audio inspiration. Unfortunately on this thread I'm not a buyer of the Transfer Company but I do agree that after reading products of the site they're of very good quality. Neather a buyer of CarlHuff's products but I only have good words on a product that really brought me to a top-level of audio listening.
To keep short:
My PCBs are made in China and the quality is stunning. And the price is 1/3 of North America's price. Delivery is very fast. Again I insist in having a good ground plane on top PCB and most of tracks on bottom side. Also voltage distribution should be made in the state-of-the-art. Fault finding must belong to the board designer.
Every low-level signal equipments have the main supply outside of boxes in my version, limiting 50-60Hz getting inside preamplifier.
My amplifiers consist of the Load Invariant of m.Self. Some works had to be done in the output stage and 130W/channel has been possible using +/- 50V supply and all Toshiba transistors inside.
Aside technical facts, only the listening help justifying the work and now I know!
Thanks m.Self for the reading on audio made available from your works.
Attachments
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What is so great about this company that you are prepared to wait six months for the PCB?
And the scale seems kitchen or garage size...20 available!
Find another more reliable supplier, it seems the other partner, not Mr. Self , is having mental issues, possibly enhanced by the corona induced lock downs.
Or he has become addicted to a mind altering substance.
Either way, he was not able to work properly.
And the scale seems kitchen or garage size...20 available!
Find another more reliable supplier, it seems the other partner, not Mr. Self , is having mental issues, possibly enhanced by the corona induced lock downs.
Or he has become addicted to a mind altering substance.
Either way, he was not able to work properly.
I think it's unwise at forums to speculate on the health of other members, whether in regard to personal or business matters. If that member cannot promptly defend or justify their situation, it amounts to public ridicule and possibly defamation.
Reading back a few years in this thread shows this problem is actually a long-standing one which predates the current pandemic by years. I suggest you look at the thread more closely and visit the STC website to read and consider what product quality, reputations and local production costs are involved, before posting off-handed comments.
Reading back a few years in this thread shows this problem is actually a long-standing one which predates the current pandemic by years. I suggest you look at the thread more closely and visit the STC website to read and consider what product quality, reputations and local production costs are involved, before posting off-handed comments.
To order all you need to do is email me. My email address is on the front page of the Signal Transfer site and also on the front page of my website at The Douglas Self Site.
Yes, it is a sad business. I am doing all I can to sort things out and fulfil back orders. I will be dispatching more PCBs this afternoon.
It seems that Douglas Self has now been able to handle the business which was not handled properly to the satisfaction of customers by the other partner.
I was speculating on the mental state of his partner, who was running the actual physical side of the business, sending the actual goods sold, with Mr. Self doing the design part, and the impression was also that he - D.Self - was no longer full time at the business.
Please read my earlier post carefully, and previous to this Mr. Self has hinted that his partner's (or colleague's ) issues are not physical.
So my logic is that the only other problem has to be mental.
I never said Mr. Self has problems.
Anyway, as an observer rather than a customer, I leave it to the members who actually want to buy the products to decide what they want to do.
Tactless, I agree, but they should man up and face the music, as the Americans might say. They have customers to answer to.
And thanks to the pandemic, people have lost their savings, and a their behavior has become , let us say...somewhat eccentric, here in India as well.
Many people have been forced to use up their savings, with their businesses and places of work closing down for long periods.
And the lock down will continue for an unknown period.
There is fear of the unknown, and a bleak economic future.
So yes, people are acting in ways that would interest a behavioral psychologist.
My apologies for any offense caused.
I did read this thread a few months back and most of the posts were to the effect that orders were placed, and material not delivered, or e-mails ignored, even posters speculating if the company was still in business.
My advice is still the same, look for a supplier you can deal with comfortably, not one who keeps you waiting without any reason.
I was speculating on the mental state of his partner, who was running the actual physical side of the business, sending the actual goods sold, with Mr. Self doing the design part, and the impression was also that he - D.Self - was no longer full time at the business.
Please read my earlier post carefully, and previous to this Mr. Self has hinted that his partner's (or colleague's ) issues are not physical.
So my logic is that the only other problem has to be mental.
I never said Mr. Self has problems.
Anyway, as an observer rather than a customer, I leave it to the members who actually want to buy the products to decide what they want to do.
Tactless, I agree, but they should man up and face the music, as the Americans might say. They have customers to answer to.
And thanks to the pandemic, people have lost their savings, and a their behavior has become , let us say...somewhat eccentric, here in India as well.
Many people have been forced to use up their savings, with their businesses and places of work closing down for long periods.
And the lock down will continue for an unknown period.
There is fear of the unknown, and a bleak economic future.
So yes, people are acting in ways that would interest a behavioral psychologist.
My apologies for any offense caused.
I did read this thread a few months back and most of the posts were to the effect that orders were placed, and material not delivered, or e-mails ignored, even posters speculating if the company was still in business.
My advice is still the same, look for a supplier you can deal with comfortably, not one who keeps you waiting without any reason.
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Thanks, my view is that you should be able to let a little go if your supplier has genuine issues, which are communicated to you.
If not, then what?
Here I got some things made, and paid for them, in October.
I was not able to go to the next town over - 80 km, as I had other commitments.
Then I asked for a small modification, 2 hours work, said I will pay whatever is extra, and told the manager to tell me a day before sending it.
The owner was tending to a sick relative, and told his manager to do what I wanted done.
That was 27 April.
He is not answering the phone or WhatsApp messages. Nor is his manager.
So I have no idea what he has done, or if he has actually done the work.
Going and coming 80 km each way here takes more than 4 hours, as I have to drive through crowded roads full of speed humps.
Add to that the actual meeting time.
So my regular work suffers.
You think I will place more orders?
Or find another supplier?
Same principle, if you have an issue, tell the customer, or refuse orders. But silence is hard to deal with by the customer, who has some plans for what he will do once he gets the material.
And ultimately an unhappy customer will always look for alternate suppliers.
That is called shooting yourself in the foot, if you are a supplier who takes his customers for granted.
If not, then what?
Here I got some things made, and paid for them, in October.
I was not able to go to the next town over - 80 km, as I had other commitments.
Then I asked for a small modification, 2 hours work, said I will pay whatever is extra, and told the manager to tell me a day before sending it.
The owner was tending to a sick relative, and told his manager to do what I wanted done.
That was 27 April.
He is not answering the phone or WhatsApp messages. Nor is his manager.
So I have no idea what he has done, or if he has actually done the work.
Going and coming 80 km each way here takes more than 4 hours, as I have to drive through crowded roads full of speed humps.
Add to that the actual meeting time.
So my regular work suffers.
You think I will place more orders?
Or find another supplier?
Same principle, if you have an issue, tell the customer, or refuse orders. But silence is hard to deal with by the customer, who has some plans for what he will do once he gets the material.
And ultimately an unhappy customer will always look for alternate suppliers.
That is called shooting yourself in the foot, if you are a supplier who takes his customers for granted.
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He had gone to Ahmedabad, about 90 km away, to visit a distant relative in hospital. I should have said visiting instead of tending...
He and his manager are recovered Covid patients, survivors is perhaps more descriptive.
The mutual friend who introduced us knows me since 1992, and him since 1975.
Our fathers, the mutual friend and I, are classmates from Engineering school, 1954.
My supplier's father and the mutual friend's father also know each other since many years, he was born in 1975...
So more old friends than customer and seller.
That is what rankled, even then he did not respond.
The sheet metal boxes were in storage since October, and he could have said it is delayed, I would not have said more than tell me when you will send it, our relation is like that.
As for the Covid emergency...I molded more than 100,000 plastic safety goggles last year for use by medical personnel for their protection, during a nation wide lock down.
I had special permits to move around in a curfew like situation.
So yes, I am aware of the situation regarding Covid.
The sheet metal boxes are also part of equipment designed for the fight against Covid.
So no I was not insensitive, just upset when someone took me for granted.
In the industrial estate near my house, 70% of the units are practically closed due to shortage of labor, compounded by a ban on non medical use of gases, so gas cutting and laser cutting of metal has stopped.
Without this, the machining and other shaping of metal has also stopped. No delivery means no billing, nor can you ask for money as nothing was supplied.
So yes, I am seeing the effects close up and am well aware of the emergency like Covid scenario.
He and his manager are recovered Covid patients, survivors is perhaps more descriptive.
The mutual friend who introduced us knows me since 1992, and him since 1975.
Our fathers, the mutual friend and I, are classmates from Engineering school, 1954.
My supplier's father and the mutual friend's father also know each other since many years, he was born in 1975...
So more old friends than customer and seller.
That is what rankled, even then he did not respond.
The sheet metal boxes were in storage since October, and he could have said it is delayed, I would not have said more than tell me when you will send it, our relation is like that.
As for the Covid emergency...I molded more than 100,000 plastic safety goggles last year for use by medical personnel for their protection, during a nation wide lock down.
I had special permits to move around in a curfew like situation.
So yes, I am aware of the situation regarding Covid.
The sheet metal boxes are also part of equipment designed for the fight against Covid.
So no I was not insensitive, just upset when someone took me for granted.
In the industrial estate near my house, 70% of the units are practically closed due to shortage of labor, compounded by a ban on non medical use of gases, so gas cutting and laser cutting of metal has stopped.
Without this, the machining and other shaping of metal has also stopped. No delivery means no billing, nor can you ask for money as nothing was supplied.
So yes, I am seeing the effects close up and am well aware of the emergency like Covid scenario.
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Hello all! Is there a BOM in spreadsheet form for the balanced phono preamp floating around here in the ether? Better yet, has anyone made a BOM in Digikey or Mouser? The BOM in the pdf that comes with the kit doesn't copy and paste nicely into a spreadsheet so I'll essentially need to do it manually. If there's no spreadsheet already, I'll be happy to share mine when I've completed it. Is there a better thread to make this request in?