photos of the delta1

delta1

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Re: photos of the delta1

Postby linux-works » April 25th, 2010, 5:12 pm

no pretty ribbon cable. and I think one half of that connector is digikey and the other side is mouser (?). so you really have to be ordering from both places to get both halves.

and once its soldered up, that's it; you don't get to break it apart and 'remote' one end, later on. marriage is for life, here. ;)
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Re: photos of the delta1

Postby amb » April 25th, 2010, 5:15 pm

linux-works wrote:no pretty ribbon cable. and I think one half of that connector is digikey and the other side is mouser (?). so you really have to be ordering from both places to get both halves.

Both are from Digi-key.

and once its soldered up, that's it; you don't get to break it apart and 'remote' one end, later on. marriage is for life, here. ;)

You could remove both connectors and then break the board if you want.
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Re: photos of the delta1

Postby linux-works » April 27th, 2010, 10:11 am

another shot or 2 of the d1 controller board:

Image

Image

on the 2nd one, this is an important hack for use of the TI (texas instruments) 8574 chips. it seems that these *NEED* pull-up resistors for the PE chips to work. the NXP/philips chips did NOT need this! this was not found until just today when I tried hacking in those 2 yellow networks and, to my surprise, that board suddenly came to life after the mod!

we will look into adding support (on the pcb) for the 'new' resistor network. for NXP, it does not seem to be needed but for TI chips, it does.

at least that is one mystery that is now solved ;) and it allows us to second-source this important chip.
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Re: photos of the delta1

Postby DorkVader » April 27th, 2010, 10:35 am

Very cool stuff, and good you caught it. I'm pretty glad I won't have to do that sort of soldering. I'm happy for the updates.

It looks like the resistor network is soldered directly to the far side(closest to the middle of the board) of the chips (well, the sockets). I suppose you can probably add holes for them on the board without too much trouble. You will move some stuff over a little to make room, but it looks like no major shifting around and reorganization would be necessary.
This will remain unpopulated completely for the non- TI chips, and it'll be filled in only for the TI ones, right? Or will it be optional for one type and required for another?

This looks un-fun (or very fun, depending on one's perspective on life) to do ones'self. We're one step closer to awesome!
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Re: photos of the delta1

Postby linux-works » April 27th, 2010, 10:48 am

it may be one of those things that 'doesnt hurt' when in the NXP chip but is needed with the TI ones. I will do some testing (others are invited, too, of course!) with both and with the r-net installed. I doubt things will work 'better' with it in and the NXP chip but I want to be sure it does no harm.

the PE chip 'wraps around' with its pin definitions (if you look at the datasheet for it). that makes 'patching' it hard. however, the tracework has been done and the relay driver chip (next in line) already 'straightened out' the weirdness and so that makes a convenient pull-up patch point ;)

in fact, now that I look at this, the bus pin (pin1) could be bent to hit the bottom-left pad on the relay driver chips and all the rest lined up and tack soldered like the photo shows. then you would not need a clip-off wire or other green-wire to connect the bus/common lead. it would really not be all that hard. I may try a few like that on my remaining test boards.

for all the NXP use I've tried, they never needed this r-network. so, I do consider patching the boards optional if you pick the NXP branded chip. if you have TI chips and they're not soldered in, perhaps return them and get the NXP ones to save yourself some hassle.
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Re: photos of the delta1

Postby linux-works » May 4th, 2010, 12:45 pm

patches!


Image

here's my 3 set of patches to the proto board.

going left to right, the first set of yellow r-networks (102LF) are there as pull-ups to the not-so-compliant TI versions of the philips port expander (PE) chips. if you use the NXP philips chips, this is not needed.

the next set of yellow SIPS (470LF) are meant to halve the relay 'bias' resistors and lower them to something closer to 20 or 22ohms. the 47ohm value was too high and it worked 'ok' for 4.5v relays but the more common 5v ones were not always latching. the new BOM update will have the better 22ohm value and that will work for both values of relay voltage, 4.5 and 5.0.

the last patch was my own soldering mistake when I didn't bend the right pin over on the last (board level, not seen here) r-network. there was nothing really wrong with it but I lost the power 'dc ok' leds on the very last bargraph segment. by making a solder bridge across the last two NON INDEX pins (ie, leave the dot or pin1 pin alone!) I was able to get my DC OK leds on each bargraph to come on. very very optional but I did it anyway. if you use the correct r-network you won't ever run into this problem.

I prefer to parallel the new 47ohm part to the lower area of the board rather than unsoldering the existing one and putting in a strip of 22ohm network. if you have NOT built yours yet, please do get the 22ohm part instead! if you did already solder in a 47ohm strip, you can patch it like I did. least perferable is to cut the old part out and clean out the holes and put a new 22ohm part in. having 2 in there won't hurt, it even doubles each one's current ability and does not stress or weaken the board.
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a small-box prototype for development

Postby linux-works » June 6th, 2010, 3:59 pm

somewhat complete LCDuino1 and Delta1 in a medium sized hammond box with 'poor man's panels' (abs plastic):

Image

Image

Image

Image

(I'll show more shots of that perf-board, by itself, next time its removed. it's fragile and I don't like to handle it unless it needs to be)

this is my current working prototype for the lcd1 and d1 system. its a single ended (single d1 board) volume control with learning IR remote, local motor/pot for volume adjustment, multi-button on front for various functions and remote power on/off via a switched 5v intended to be used to control a solid state relay (SSR) on your amp.

the multibutton is as follows:

- if power is off, press and release this to power on system. a 5v logic (low current) line goes high and that is sent out from a rear panel power jack.
- if power is on and its been 3 seconds since system power-on and the button is pressed again, 'config mode' is entered. this is only needed once to program the IR handheld remote
- if power is on and its been longer than 3 seconds (ie, normal mode) a tap on this button will toggle muting the relays (whatever the user defined 'mute' dB to be). press to mute, press to unmute, etc.
- if power is on and the button is pressed and held for a few seconds, amp power is then turned off via the switched 5v ttl line and a small animation appears on the lcd to show that power is going off. it also allows you to release the button so that it won't turn back on again if you hold too long ;)
- finally, the led on the button can be mapped to 'IR command received' or it can be 'power=ON'; whatever the user wants. I like mine to blink when a valid IR button is pressed and stay off the rest of the time.

on the rear, I have a test led connected to the TTL control line for the amp, which is good enough to test the software. if the led comes on, my amp would, also ;)

I have been using TRS jacks lately since they are a single hole to drill and can be expanded out to dual rca's easily (shown). one jack is line-in and the other is line-out.

the IR module is simply hot-melt glued to the back of the red neon light bezel (that's what it came from).

the largest ribbon cable is the relay control line group that goes from the d1 control board to the d1 audio relay board. when you turn the volume knob or use the IR remote, these lines become 'twitchy' and pulse the relays. after the relays are pulsed, this line group carries no current and is at 'rest'.

the smaller ribbon cable (bent at angles) is the i2c group and has 4 active lines: 2 for power and 2 for i2c. that would go to the lcd1 board.

there is a small 'free hanging' 6pin male header on a cable. that's my debug/upload cable and it mates with the $20 usb/serial cable that you need to write firmware into the lcd1.


general note: I used single sided pc board and that was a big mistake. I keep forgetting this ;) the problem is that you need strong holes with plating thru them and traces that are solderable on both sides. you need some strength to hold the molex connectors since they get plugged and unplugged a lot. and you also need a place to tap-solder wires to and this is very very hard on single sided systems. most of the connectors are 'raised' to allow me to get my soldering pencil on the 'top' of the board where I need to solder ;( not really recommended but good enough for a proof-of-concept and it actually does work.

the idea behind this 3 layer sandwich is to keep the middle module mostly 'pure' and not modified. the arduino board (lcd1) sends out its cpu lines via male header pins and these are tapped into by the 3rd board, the perfboard, and that is where the 'application specific' wiring happens. I kind of like this approach and it lets me remove things and work on them and not have a tangle of wires. otoh, you can see how MANY connectors there are here! its quite a nest, isn't it? ;) at some point, I do plan to draw a wiring diagram key or legend and actually include it inside the box. or number the jacks and put tags on them. you really need to be sure you can put the right wires back into the right molexes.

I think there's enough room in this box to support stacking so that you could have balanced d1 boards. I have not tried that, yet.
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Re: photos of the delta1

Postby Nebby » June 6th, 2010, 6:04 pm

I'm really looking forward to the release of the delta series, my planned three channel build in a par metal case has a good amount of open space right by the inputs :D
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Re: photos of the delta1

Postby juaquin » June 6th, 2010, 11:14 pm

Same here, I'm 80% done with my GainClone and can't wait for some relay attenuated goodness. Keep up the good work!
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Re: photos of the delta1

Postby linux-works » June 19th, 2010, 11:04 am

I'm going to hack my own board (lol):


Image

this is a 7bit build (7 relays, 1dB/step) and I just hate wasting that last relay slot ;) so what I have planned is to use it for an input selector, poor-man's fashion. I'm going to take that 8th relay (the omron latching one) and remote it on a smaller perf board and put that near the input jacks of my amp and let it select A or B as inputs. just that simple. I like the fact that, since its latching, it remembers its last set state. for i/o selectors, that's really handy.

it will take an update to the code to partition off this 'unused bit' (the 8th bit) from the volume up/down stuff and just mask it off so that when the user selects A or B as the inputs it will leave the volume bits alone and toggle only this one 8th bit.

I don't know how many people will do 7bit builds or 8bit builds (for volume control) and out of those that choose to do 7's, how many will want to go to the trouble to 'remote' the final relay off near the input jacks. but its not a lot of extra software and I love the frugality of being able to use every last bit for 'something' ;)

note, on that final relay pcb area, there are 2 wire shorts that you install to jumper over that last r/r2 stage and just connect to the output. those cutoff leads from resistors are all you need to bypass around the final stage, in terms of the volume control signal path. then, you simply hijack the control wires for the relay (the 2 color ribbon cable that I used going to a molex) and run that to the remote'd relay. that takes care of the control side. for audio, the center pins of the relay are the 'output' and the opposite pins are the center and ground of the rca inputs (or equiv). just regular old A/B selector stuff here; the only trick is that its a latching relay acting like a DPDT switch and the control to the relay comes via this hacked up vol control r-2r board and some magic firmware that tells bits where they belong in life ;)


Image


more to come as it gets finalized.

also worth mentioning, AMB likes the idea of having this last relay be a true mute (short to gnd) style function. that's another possibility that is simply a matter of turning on a software setting and actually installing that relay in the final slot but not using any R's and only using opens and shorts for series and parallel. and if that relay is the last in the signal chain and the input to it is 'open' and the center is connected to gnd, its just like a ideal pot being at the very min of its rotation and is actually a true full mute. that's another possible mapping of the last relay in a 7relay build.
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