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Old 8th August 2007, 07:14 PM   #11
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gbyleveldt,
That is absolutely beautimous!
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Old 8th August 2007, 09:12 PM   #12
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Very nice indeed.

Can I ask you how much was your VFD screen? I don't manage to get one at a good price.
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Old 9th August 2007, 02:30 AM   #13
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Quote:
Originally posted by Raka
Very nice indeed.

Can I ask you how much was your VFD screen? I don't manage to get one at a good price.
Thanks!

I think I paid a shade over $100 for it (shipping to South Africa is a killer) and got it from Farnell. Not cheap, but worth it I think. Anything else would've looked 'home made'
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Old 9th August 2007, 05:03 AM   #14
Raka is offline Raka  Europe
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Definitely they look, and can be looked, much better than a LCD, for sure. But my blue backlight LCD doesn't look "homemade"!!
I'll search the Farnell book, and will also continue to keep an eye in every thrash bin...
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Old 9th August 2007, 05:31 AM   #15
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Hi Raka,

My VFD is a Noritake unit and is quite low tech compared to the rest of the stuff they got. Check here I battled to get a better supplier than Farnell, but you might have better luck being in Europe.

The back lit blue LCD does look good, but can be a little hard to read from a distance. Got any pics of the result? Sorry Error401 for hi-jacjing your thread...

Cheers

Gert
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Old 9th August 2007, 06:46 AM   #16
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Quote:
Originally posted by gbyleveldt
Hi Raka,

My VFD is a Noritake unit and is quite low tech compared to the rest of the stuff they got. Check here I battled to get a better supplier than Farnell, but you might have better luck being in Europe.

The back lit blue LCD does look good, but can be a little hard to read from a distance. Got any pics of the result? Sorry Error401 for hi-jacjing your thread...

Cheers

Gert
No problem, better to have discussion, even if the discussion is a bit tangential. I'm actually interested in this because I couldn't find a decent source for appropriate graphic VFDs, which I would eventually want. All I can find is 20x2 (and similar) character VFDs on eBay. They're almost as cheap there as LCDs and I sorta wish I bought one instead of the blue backlight LCD I grabbed to toy with; they're certainly more readable at distance, but I think character LCDs look nicer than character VFDs.

Any ideas where to find VFD colour filters? I googled around and couldn't seem to find a source other than a couple manufacturers that didn't have contact info on their sites.

On topic: I got my microcontrollers and other gadgets (Atmel ISP programmer) that I ordered on the weekend. After using PIC in the past, this is so nice. The AVR architecture is just a blessing compared to the PIC one that I just can't blast often enough. Took all of an hour for me, having never used an AVR before, to get I2C working and lights flashing out of two separate IO expanders. It took almost a week for me to get a similar demo going with SPI and PIC with the TLC5940. Fun, fun chip that one. I'm almost tempted to toss one in this project for some fancy LED effects to exercise the excessive MCU cycles - but the switching noise...

PGA2311 interfacing is next, and shouldn't be too much harder. This digital stuff is so fun and easy compared to the analog
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Old 9th August 2007, 06:55 AM   #17
Raka is offline Raka  Europe
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Interfacing with the PGA is really simple, you will see. Let me recommend you something: as the pga has zero crossing detection also for the mute action, for the source changing you can do mute-change-demute. You can avoid potential clicks in the change.

PD: I tried some time ago to search in ebay for VFD's, but without success... I couldn't find anything. I have to improve my skills in ebay searching.
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Old 9th August 2007, 07:07 AM   #18
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Quote:
Originally posted by Raka
Interfacing with the PGA is really simple, you will see. Let me recommend you something: as the pga has zero crossing detection also for the mute action, for the source changing you can do mute-change-demute. You can avoid potential clicks in the change.

PD: I tried some time ago to search in ebay for VFD's, but without success... I couldn't find anything. I have to improve my skills in ebay searching.
That was already part of the plan . I was actually going to quickly ramp the volume down, mute, switch, unmute, then ramp up to the new (offset) level over total maybe 250ms. I find abrupt source changes very disconcerting (or maybe it's just that smooth ones are so much nicer), and these relays switch in 3ms; at full speed (<10ms source to source) I'm sure it would bother me.

Scarily enough I'm actually thinking this should be a fairly easy project, and maybe even doable home-etched with a few jumper wires .

Ahhh! Now off to the beach for 4 days and forget about electronics...my AMP5 kit just assembled is not working
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Old 9th August 2007, 09:01 AM   #19
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I don't have the ramp implemented, but in the future I will include this as an option. For comparing sources it's better not to have the ramp.

Once you finish the project, and debug everything, you realize that it's a simple project.
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Old 10th August 2007, 06:23 AM   #20
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Quote:
Originally posted by error401

Any ideas where to find VFD colour filters? I googled around and couldn't seem to find a source other than a couple manufacturers that didn't have contact info on their sites.
I also battled with that one, but I ended up hacking up an old VCR for it's filter. Works beautifully! You might want to pop around to your local repair shop and go through their old VCR's to have a look.

Quote:
Originally posted by error401

On topic: I got my microcontrollers and other gadgets (Atmel ISP programmer) that I ordered on the weekend. After using PIC in the past, this is so nice. The AVR architecture is just a blessing compared to the PIC one that I just can't blast often enough. Took all of an hour for me, having never used an AVR before, to get I2C working and lights flashing out of two separate IO expanders. It took almost a week for me to get a similar demo going with SPI and PIC with the TLC5940. Fun, fun chip that one. I'm almost tempted to toss one in this project for some fancy LED effects to exercise the excessive MCU cycles - but the switching noise...

PGA2311 interfacing is next, and shouldn't be too much harder. This digital stuff is so fun and easy compared to the analog
My first big AVR project was also this one. Most of my work was with TI MSP's in the past, but in general AVR's are now my favourite!!

I was also concerned with the CPU clock inducing noise into my system and was going to put the CPU to sleep if it wasn't doing anything, but it turned out that with the boards split the way I did it I could not detect any CPU noise (tested with a scope) on the output. Admittedly, I'm not really using any gain in the PGA, I'm always only attenuating (ie. I'm always below 0dB).
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