Hawkeye Posted January 5, 2011 Report Share Posted January 5, 2011 (edited) Viewing the slow LCD display updates next to VFDs has become quite a burden lately :-) I haz made some successful color-altering tests with color foil, which creates great red character output from a standard vfd... Of course it is not a cheap modification, but the mb6582 is my fav synth currently... so the question is... Has anyone successfully installed a 4x20 VFD in a MB6582? Noritake advertises some as LCD drop-in replacement alternatives... Eg. CU20045-UW5J Datasheet: http://www.farnell.c...heets/14273.pdf It seems that it will physically fit... but will it cause too much load on the 5V chain (275 mA typical)? I have a standard C64 PSU, 9V only option on baseboard and 8x8580 installed. Thanks for your opinions, Peter (If this works out, I will update the photo tutorial, of course :-)) Edited January 5, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
phunk Posted January 5, 2011 Report Share Posted January 5, 2011 woah..that thing is expensive...BUT NICE! Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 5, 2011 Author Report Share Posted January 5, 2011 gets cheaper when we do a forum bulk order of 100pcs :) Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 5, 2011 Author Report Share Posted January 5, 2011 rethinking this... is there an easy way to create a 300mA load on the 5V chain so that I can test prior to buying one? I have lots of standard 0.25W resistors flying around, how would I chain them correctly? Quote Link to comment Share on other sites More sharing options...
philetaylor Posted January 5, 2011 Report Share Posted January 5, 2011 (edited) Ohms law to the rescue..... To get the resistance required to generate 300mA on a 5V supply, you divide 5(V) by 0.3(A) which gives you 16.6Ohm's. The power required (in Watts) can be obtained by multiplying 5(V) by 0.3(A) which is 1.5W. If you put equal value resistors in parallel, it half's the resistance and doubles the power handling capacity so you could put 10 x 160R 0.25W resistors in parallel which would give you 16R which would produce a load of 312mA on a 5V supply. You could probably get away with 5 x 80R but they might get a bit warm :) Edit: The actual formula is: 1 R(total) = --------------------------- 1/R1 + 1/R2 + 1/R3 + 1/R4 ... Cheers Phil Edited January 5, 2011 by philetaylor Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 5, 2011 Author Report Share Posted January 5, 2011 (edited) Great and thanks a lot to you and mr ohm senior :-) I will use then 13pcs 220R resistors in parallel giving 16,92 ohms which will cause 296 mA load according to the formula, that is close enough :-) Edited January 5, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
audax_axon Posted January 12, 2011 Report Share Posted January 12, 2011 second the notion Re. interest in participating in a bulk order for the noritake alleged drop in. I picked up an IEE VFD that showed up cheap on Ebay, but found that it's mechanical dimensions were slightly too large for the spacing in the control surface PCB. Haven't yet gotten to the point in assembly where I could test compatibility, but had pretty much written it off because of the size issue. Quote Link to comment Share on other sites More sharing options...
audax_axon Posted January 12, 2011 Report Share Posted January 12, 2011 this topic also brings up the interesting question, Are the worst case scenarios for power consumption on the various supply rails using all 6581's, 8580's etc. known? All the references i've seen in the docs simply refer to using the C64 PS or building an externally regulated unit, if one were building one, what should the carrying capacity be on the various rails to account for all possible conditions? Quote Link to comment Share on other sites More sharing options...
strophlex Posted January 13, 2011 Report Share Posted January 13, 2011 Based on datasheet calculations, the 5V supply usage is ~1000mA. PICs are 23mA each, 6582A SIDs 70/100mA each, LEDs 100mA max, LCD ~280mA. If the SIDs are at the max current, then it's ~1200mA. 9V supply usage is ~320mA I would say you would be safe with 2A on the 5V and 0.5A on the 9V/12V. I am building a PSU now and I use a 15VA 7.5V transformer (2A) for the 5V and a 15VA +12V/-12V center tap transformer (0.625A) for the 9V and it works. Right now I have some noise in the audio, but I don't think it is because the transformers are too small. Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 13, 2011 Author Report Share Posted January 13, 2011 (edited) I have the feeling that the noritake VFD is not greedy on power, as it is rated the same (275mA) as some LCD backlights. That is a good character trait and makes it really useful as a drop-in lcd replacement :-). Ok, here is a pic with added load on the 5v chain. My setup is a standard C64 power brick, 8x8580 - I am playing some notes on all 8 sids for some time now and so far everything looks stable, will leave it on for a little longer, though... The breadboarded resistors actually only add ca 190mA current consumption on the 5V rail, because my multimeter is a very el-cheapo variant and can´t measure higher currents than 200mA. That´s why I left the backlit LCD connected... in conclusion, if the VFD does not take more than 200mA more than my used backlit LCD (which is rated for 200mA), it will work. Of course, using a newly built custom PSU, you are on the safer side, just make sure that you catch no noise from switching PSUs. Regarding the bulk order - I am not sure, that this is going to happen, as the items are quite pricey and we would need to get 10 people interested in them with cash prepayment for a significant rebate - i would not like to run such a thing for sure, because of the hassles involved. I will order one noritake VFD soon, as I love the MB-6582 (really!) and will keep you posted regarding the compatibility: dimension-wise, as well as driver-wise. I am quite confident now, that for a 8x 9V SID setup (8580/6582) at least the C64 PSU is good enough for use with this VFD. Edited January 13, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted January 13, 2011 Author Report Share Posted January 13, 2011 (edited) Sorry for double posting - just before ordering, I have identified a potential fitting conflict of this VFD, if you look at the vacuum tube and the components on top of the vfd glass case on the right diagram in the datasheet: http://www.farnell.c...heets/14273.pdf they will collide with the top window cutout of the control surface pcb and the tactile switches there, if you look at the second photo here (sometimes i am glad for photo documentation :-)): so either the vfd has to be mounted ca 7mm deeper, which might be problematic because of the already quite stuffed pactec pt-10 or we have a fitting problem... Argh &§"/$(! Edited January 13, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted June 15, 2011 Author Report Share Posted June 15, 2011 (edited) If anyone else is also VFD hungry... the above-mentioned display from Noritake fits quite nicely into the MB6582 (its outer dimensions regarding components on the pcb differ from the schematics in the datasheet). I will update the mb6582 photo tutorial soon with pics and installation guidelines. The display needs a little bit of driver patching, though. I´ve updated a clcd driver, that works fine for me now, you can find it here: Best regards, Peter Edited June 15, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted June 16, 2011 Author Report Share Posted June 16, 2011 (edited) And a demo pic can be found here (will add another one after it is installed in the PT-10): http://midibox.org/f...ewimage&img=837 Ah, lovely VFD... mmmm! :-) Edited June 16, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
jojjelito Posted June 16, 2011 Report Share Posted June 16, 2011 Mmm, looks tasty! Wonder what the final pic in the box will look like? A time lord you say, but the question is: Are you justified and ancient, and do you come from Mu mu land? Bring back KLF and resurrect Tammy Wynette while you're at it :sorcerer: Quote Link to comment Share on other sites More sharing options...
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