Yes, indeed sorry guys, there is a typing error in the appendix. It should read 197.1 instead of 201.6 if you want a 10 mm cut width centered about the connector. The connector itself is 9.2 mm wide.
I'm currently overseas so I can't update the documents on the website. I'll do that in a week. Note that the placement of the cut in the drawing is fine - it's just the reading which is wrong.
Nice job Bengt, and interesting design! So is the board hanging upside down? And the display comes on the top? Looking forward to the finished product
Do you mean you have the channels L-R inverted?
Yup, should be fine! And definitely worth a try at this price
Nice job Bengt, and interesting design! So is the board hanging upside down? And the display comes on the top? Looking forward to the finished product
Yepp, it's hanging uppside down. There will be more pictures in due time.
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Soo...trying to load some coefficients for FIR filtering i Najda Under Control. Tried text files and wav but is getting a "Invalid file" message. What kind of files are expected?
Best regards,
Mattias
Hi Mattias,
A text file should do
Have a look at the attached files. This is a minimum phase 2k xo@48kHz.
have fun!
best Paal
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Thanks, your files worked as expected. Can't see what is wrong with my text files then. See the attached file (100 taps):
Any progress on checking the voltage with this? Attractive at that price!
Acquiring the bits before I buy the board here. Somehow when ordering the 1602 OLED that we now know is not HD44780 compatible, I ordered the WRONG one thinking I was getting a different colour version;
Oled 2x16 Yellow/green On Black - Price For 1 Each - MCOC1602BWMYE | eBay
http://www.farnell.com/datasheets/1485419.pdf
Nevermind! No mention of HD44780 so I think it will not work - but correct me if I'm wrong please. Have seven days to return it, though I may do an exchange for this;
Lcd Module Alphanumeric 16x2 Price for 1 Each - MC16021E8-SBLW | eBay
http://uk.farnell.com/everbouquet/m...2/dp/9449051?Ntt=EVERBOUQUET+-+MC16021E8-SBLW
"utilise the latest white LED technology for the backlight whilst maintaining compatibility with the standard HD44780 driver format"
Not cheap but the price is similar through Farnell and CPC, so I am thinking it must be decent unless anyone advises otherwise? White on blue may be a taste issue of course
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Hi Paal,
Your Acourate screenshot doesn't show the phase. I actually don't know what it shows because the units on the vertical axis don't make sense.
A linear phase filter will exhibit a phase that is a straight line if the frequency spacing on the horizontal axis is linear. Note I said straight line, not horizontal line. Most audio plots have a log frequency spacing because this fits better the way we hear pitch, and Najda Under Control is no exception.
The mathematical expression of phase vs frequency is something like:
phase(freq) = a * freq + b, where a is the slope of the line (connected to the group delay) and b is the phase at DC (i.e. when freq = 0 Hz).
So if you're looking at the phase of a linear phase filter on a log frequency scale, you actually won't see the straight line...
Then comes in the wrapping of the phase. In the above expression, as freq is growing, the phase is at some point exceeding 180 degrees. Wrapping consists in adding multiples of +/- 360 degrees in order to keep the phase in the [-180, 180] degrees interval. This translates in jumps of the phase plot from bottom to top.
Does this answer your question?
Best,
Nick
Acquiring the bits before I buy the board here. Somehow when ordering the 1602 OLED that we now know is not HD44780 compatible, I ordered the WRONG one thinking I was getting a different colour version;
Oled 2x16 Yellow/green On Black - Price For 1 Each - MCOC1602BWMYE | eBay
http://www.farnell.com/datasheets/1485419.pdf
Nevermind! No mention of HD44780 so I think it will not work - but correct me if I'm wrong please. Have seven days to return it, though I may do an exchange for this;
Lcd Module Alphanumeric 16x2 Price for 1 Each - MC16021E8-SBLW | eBay
MC16021E8-SBLW - EVERBOUQUET - LCD MODULE, ALPHANUMERIC, 16X2 | Farnell United Kingdom
"utilise the latest white LED technology for the backlight whilst maintaining compatibility with the standard HD44780 driver format"
Not cheap but the price is similar through Farnell and CPC, so I am thinking it must be decent unless anyone advises otherwise? White on blue may be a taste issue of course
The OLED above is probably not OK as you noticed.
The second display should be fine, they seem to suggest it can replace a standard LCD in an existing product. It's maybe worth double-checking with the seller (ask the datasheet).
Hi Nick,
You are talking about the first screenshot?
The first Acourate screenshot shows the impulse response of HP and LP filter and the second screenshot is the phase vs frequency. it has +- 180 degree on the vertical scale and log frequency on the horizontal axis.
best,
Paal
I'm talking about the second screen shot. I understand the +/- 180 vertical axis is meant for degrees - but the plot itself is not the phase of your filter in the +/- 180 degrees interval.
Here's an example of linear phase plotted. You will see this straight line I was referring to (again, straight line because linear freq spacing).
I don't have Acourate, so I can't tell you what's going on. Could it be that you have set the phase units to radians but for some reason the units on the plot are degrees?
Best,
Nick
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Thanks Nick,
The datasheet is in the second link I posted and is pretty vague in that respect I think. Page 10 describes recommended resistors for a power supply which I do not understand.
I just want plug and play so may get a refund and wait for something tried and tested by other builders on this forum.
As I understand it, there are very minor differences between the OLED protocol in question and HD44780. I still hope that you take a look on the link I posted previously and consider the possibility of including support for OLEDs. They are really beautiful displays imo.
No mention of the driver chip in the datasheet. I suggest you ask the seller on ebay, he's the one saying that the part is a possible substitute for standard LCDs.
The last page is about adjusting contrast with a pot. On Najda, there's a PWM replacing the pot. You can ignore this page.
As I understand it, there are very minor differences between the OLED protocol in question and HD44780. I still hope that you take a look on the link I posted previously and consider the possibility of including support for OLEDs. They are really beautiful displays imo.
Hi Mattias, I'll look at the details in the datasheet and I'll let you know how it goes. I'm yet to find what these 'minor differences' are