Jidis

Hey again, I think it can help, but it's effectiveness will depend on the signals and frequencies you're trying to block. Hopefully someone more knowledgeable here can explain. I had to laminate sheet aluminum to both of my isolation cabinets in the control room due to the fact that I was running "caseless" computers. Years ago I wanted to shield either a CRT or a speaker, and a tech here explained that in order for it to be effective in that range, I'd have to use expensive mu-metal, or go with some ridiculously thick stuff. Shielded speakers supposedly use a specially designed magnet which counters the emissions. I'm guessing balanced transmissions and proper distance are the most realistic solutions. -- Sorry if you already knew all that ;) George  PS--- I just remembered that with certain noise, any little gap can allow passage. I had to couple metal screening to the inner shields where my fans were. In other words, I'm not sure a rack which was wide open on two sides would defeat the purpose. I know there are a lot of them in the server/network industry, but it may be more for the durability. PSPS------ Also remembered your mention of lighting/dimmer noise. Another thing to try might be isolating your gear from the noise makers. I've got variac dimmers in both my rooms to kill the regular dimmer buzz. An iso-transformer or some filtering may help if it's "safe" enough. I've got one here as well, but I think it makes as much acoustic buzz as anything it knocks off the power line. ;D

Jack, I just noticed these if you're interested. Pretty inexpensive ($1 each), but no housing. -George http://cgi.ebay.com/SPST-ILLUM-RED-P-BUTTON-SWITCH-MS661R_W0QQitemZ2598535838QQcategoryZ26211QQcmdZViewItem -- Check his store too. He's got green, red and some 74HC165's

Jack, Yes (I think). It's way back at the beginning of this thread. I think it was just pushing the "end" line to the line number that MPASM wanted (using blank lines). -Take Care

Ingebret, I've built more than I care to think about ;) I learned from bad experiences to be a bit generous on the i.s. dimensions. I usually go 19 &1/8" on the inside width. The rails are really easy to shim inward with a couple thin strips of cardboard or rubber, and you won't notice it at all. There's nothing worse than going the exact dimension and finding one piece of gear who's ears are a tiny bit wider than the others. I give them a fraction more at the top and bottom as well. The rails will give you the proper space to space dimension, with the exception of that one device with the "tall" chassis screws that seems determined to destroy all your other hardware. -Good Luck

I don't think they should go away after a second though. (?) I use the debug in MS for the ability to send text to the display for layout purposes, but I guess you'd need a functioning connection first. I'm only familiar with the two displays I've used here (16x2 & 40x2, both with 44780 chips and 14 connections + 2 for light). I think a 4 bit connection requires a little more work than that. Maybe someone more knowledgeable here can help out. It looks like there are some software edits involved (search the forum for "4 bit LCD"). If that's the 1022 datasheet I just looked at, I think their janitor may have drawn that up. ;) Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Good luck! George

Hey Moebius! It was the same connections from the schematics, just on a board with the LED's. I think I went by the mtc_extension.pdf schematic. The clock display only needs 3 595 chips (one for the 8 anodes, one for the left 4 cathodes, and one for the right). I've got them on a board with the digits and the 16 220 ohm resistors. It's got a five pin connector carrying the supply, the ground, and the three lines to the 595 chain. You're looking at 24 lines to the LED circuit for this thing, so I figure it's about as easy to put them all together and just have the five lines going to that. -George Â

Hi Jason, That timecode display is my favorite of the MIDIBox circuits. You just need the MIDIMon from www.ucapps.de with the MTC LED display. You can run it without the LCD connected for what you're doing. You'll need the MBHP "Core" module for the guts with a programmed MIOS PIC chip (or a PIC with the MIDIMon app already on it). You need seven segment displays with common anode LED's for the display. You can go with whatever configuration is convenient, as long as they have separate cathode pins for the segments and you have eight digits total (I use four dual digits). I don't think there's a board for that, but the schematic PDF is on the website. I've built a couple with the three HC595 shift registers onboard, but I guess standard procedure is to use the MBHP D.OUT module for that part. If you, or he, needs any help with the display half, let me know.                                       - Take Care George Â

Thanks! I was afraid of that. I guess if I get a bunch of cheap boards, I probably should at least go with something thick enough for multiple projects. I'll probably go .062. -take care

Moogah, They look like Digitast buttons. I have sort of a history with them. I had to send back a used JL Cooper CS-10 for button cap replacements, and they all self destructed afterward. They sent me more caps, and they did the same thing (the plastic hinge part cracked and fell apart). I eventually had to give up and etched a new daughterboard for a different style of switch, with "Digitast Sucks" written in the copper. ;D I have since bought several batches off eBay and don't believe that was a common problem. Best I could figure, something had changed in the manufacturing dimensions over time, and the current cap was no longer an "exact fit", putting too much outward pressure on the hinge tabs. I have narrow gray ones here, wide blue with a red LED, and wide black with dual red and yellow LEDs. They all feel quite solid. I think I remember them being from Germany. Digikey sells them here in the US, and also appears to have something by E-Switch (5500 and 5511 series) and ITT Industries (REKN series), which look about the same. The price was what kept me from just replacing all the Coopers. It looks like the E-Switch is a bit less money. Good Luck -George PS- I think I remember them in the old MidiBoxPlus pictures too.Â

Speaking of DIY VU's: I searched, but never found a good VU circuit with peak hold. If anyone ever sees one, I'd be interested. -Thanks! George

Moogah, Thanks! - That's weird, that is almost what I put on there. I blew an 18f452 with the bootloader and MIOS1.8, as well as erasing it, reading it and verifying it successfully. I did everything except use the chip in a MIDIBox ;D It looks fine, but I didn't get the 13.7v in the MCLR test at pin 1. It was something in the high 12 range (maybe 12.9v) and that "delay" fader was at minimum. The Vss/Vdd test was a fraction lower than 5v as well. I'm not sure what the tolerance is on this stuff, but I do have a backup programmer. -George PS- I think 9 pin "straight-through" cables with most of the lines connected need to be on the endangered species list.

Hey Rowan, You probably want to go with "bars". They'd be easier to wire and cut holes for, and there are a bunch on eBay,etc. I've actually got some coming, but they're all red. I've seen the "stoplight" style multi-color ones too. If I can find a link, I'll try to post back later with it. I thought you meant individual holes at first. I've been wondering lately how anybody cuts those. There are some cool looking rectangulars out there. I saw some today with the plastic mounts too. -George

Hi, I'll be running out of copper over the next week or so. There are some great deals on .025 single-sided boards, but what I'm used to looks to be in the .062" range. Has anyone used that thin one a lot, and is it OK even for boards which directly support pots or buttons (with standoff bolts to the panel or chassis)? -Thanks!  George

Hi, I etched a JDM board and had everything but the 8.7(or 8.2) zener diode on hand. I found a 9.2 and a 7.something, but nothing in the eights. Is it safe to go up or down a value, and if so, which one? If not, I've been using a Willem. I just want one for home. :) -Thanks!

Davo, I had to decline on the wipe-on etch thing. It appears you need the TRF to do that. I guess you'd wipe the print off without it. I'll probably be ordering the green and white this week when I get up a good DigiKey order. I'm looking forward to doing some white on black, but I'm wondering how easy it will be to check over the black toner transfer before you apply the white. I usually don't hit a perfect transfer on my first attempt, but it's really easy to wipe it off and do another. This last one was an eight digit, green numeric display. It's only about 1.5" by 4 or something, with four of the full size (20mm?) dual modules, the three 595's, the resistors, and a five pin header. It's packed real tight with some really small traces, but I had to go with a bunch of jumpers on the top. They're multi-colored, insulated leads, smushed down under the components, so they actually look sort of cool. Every time I do these things I have to remember the heat/pressure/time ratio. That's why I usually don't get a good one on the first attempt. Two things I'm catching on to: Less pressure for less time, moved frequently around the board with the tip of the iron, and also making the boards an eighth inch or more larger around than my print. They trim down fairly easy on a belt sander. I've found the edge traces to be the ones which don't always stay on the copper, so I do that as well as thickening up the outer ones until they hit the edge. If there are pieces of traces which come off, there are usually one or two in a small area where I didn't apply enough heat (never really anything long). I've discovered that it's easier to draw a splotch of sharpie ink over the whole area, rather than trying to redraw the small missing chunks of trace. You can slice out the center parts to separate the traces with a pencil tip x-acto blade after the etching and still have nice straight lines. My total ironing time probably isn't much more than 3 minutes. When I initially hit it, I will usually press the full base of the iron over the whole board for a bit, so that it glues itself down and I don't risk having ripples in it by working from end to end. Gootee's got similar instructions on his site. With this new Staples paper and the printer I'm using, it doesn't look like there's much danger in extending the ironing time. I think if I keep the iron moving, applying light pressure in small spots, I won't overheat it and I'll have less chance of having any parts that didn't stick. I've blurred the traces a bunch of times from either pressing too hard or letting the heat sit too long in one spot. I'm also wiping the top of the paper afterward with a wet paper towel to cool it, and I've been squashing the iron into it one last time after it's soggy. I keep a spoon handy in case it tries to stick to the iron. I don't know if this helps, but I see lots of mentions of briefly reheating stuff after the main heating for better bonding. The Staples paper is weird. It sort of rolls off in beads after you get it wet, and leaves a film of paper stuck to the surface. This comes off with more rubbing, or a toothbrush and water. That stuff is all or nothing. The parts that stick properly are hard to get off, unless you use solvent or steel wool. I also usually wipe it with a wad of wet paper towel to get the initial thick layers of paper off. Pulling it off the board seems more dangerous. The old paper would peel off clean, leaving a slight gooey residue after it got wet enough, but it seemed the traces were more fragile and more likely to lift off with it. It still worked pretty well, but the procedure is a bit different. I think that type of photo paper may be the easier one to find. The printer I just got is a Sharp FO-2850 fax/laser. Gootee uses the HP LaserJet 4. I think a bunch of the HP's use the same toner, but many printers may work just as well. The Sharp was given to me. I looked at that Pulsar laminator too. I'm not sure what it handles. It looks like it may just be for the paper or something (5mil maybe). The model is actually a GBC Creative Laminator (I think I saw the model# too). It wasn't really made for PCB's and there are about a zillion different similar units on eBay,etc., so if you go that route, you may look around to see if there's a heftier one which is used for the same stuff. I wish they'd start selling the colored TRF in rolls without the whole bundle. The green and white are very affordable. I couldn't find anyone outside of Pulsar selling it. Let me know if you see any.                                              -George PS-- I "flipped" the plastic tray of ferric chloride off the bathroom sink on the last etch :o It splattered across me, the wall, the floor, the cabinet and the bathroom door. First and LAST time for that one.  Â

For anyone interested, I read a tip in a link for toner reactive foil that Davo posted a few days ago. It involves "wiping on" the etching solution. I'm coincidentally soaking some paper off an MTC display board in the other room, and was going to try it for the first time. If I'm not too tired, I'll post what happens tonight (otherwise tomorrow). http://www.pulsar.gs/PCB/a_Pages/5_Support/4b_Tips_Tricks/Tips_Tricks.html -George

You should be able to with a 6 position rotary switch and fixed resistor values that would put you in the correct waveform states (2k intervals maybe). Just bring one line in and take the resistors out from the last 5 pins (1st is no resistor/0 Ohms) at 2k,4k, etc. up to 10k (those numbers are guesses). I'm wishing for the same thing, only with a momentary switch and LED indicators (hit the switch to bounce through the different values, and the lights change). That way, when you change patches or plugs, the knob wouldn't be pointing to the wrong setting. -George Â

TK and Kurt- FWIW, I didn't have much trouble moving the display elements around on a 2x40 using the MB64 files, and I barely know what I'm doing ;) I've played with the main display page layouts, but there's lots of stuff that seems like it would need to be moved around to use the wide LCD. Nothing frightening, just a bunch of nudges and added characters. I've been fighting with some button mode changes the past couple nights, so the LCD offset thing is a fond memory. Now that I've seen Nuendo's ability to transmit the mapped generic remote element's MIDI messages from the program, I don't see much reason to go LC either, and the MB64 code seems written to be customized. I do like the MTC display and the track metering, but there's always MIDIMon for one of them. -George Â

Yeah, Lexan's the common one here too. I think I've got some of each, but it's mostly Lexan. -Good stuff!

Good that you got it back! I've hit the "mangled MIOS" wall several times since I replied to this and haven't been able to get a MIDI dump through at all, so it may be something to consider when working out the internal layout of a box. My programmer is connected to a computer only a few feet away, but the ZIF socket only holds up to 32 pins or something, so there's an adapter hanging off with a regular cheap DIL socket >:(Â I'm not sure how long my PIC might keep all of it's legs. -George PS- Keep in mind, I have been making quite a mess of some of the .inc files. I doubt this firmware damage is very common.

Synapsys, Thanks for the additional info! When I ran into them, I had assumed that all the macros and stuff had to show up in the 1st column. Then, to make it more confusing, the web searches for it turned up rgoto's from a bunch of "non-PIC" code. I'm still new to PIC assembler and my only paper book is more or less on an "elementary" level. I run into lots of stuff in TK's programs that it doesn't cover and I have to go looking for. If any of you have any suggestions on a more thorough current book, which covers a broader range of info, I'm anxious to get one. The one I started with was "Easy Microcontrol'n" by Square One, and then it was straight to source comments and datasheets. ??? -George

The dedicated "function" buttons I suppose. Like the display and snapshot buttons. -Take Care

Roger, you've been watching too much "Night Rider" ;D -George PS- There's cool looking gloss black plexi around too. I've got a chunk that I scavenged off the door of a dead dishwasher.

Raphael, Thanks! I had sort of assumed there was more to it than that, and that it was a standard since it looked like the regular goto. -George

Synapsys, If you don't mind me asking (or changing the subject)- What exactly is Thorsten's "rgoto" instruction? I couldn't find it in any instruction set listings or web searches. -George