Building Aleph P clone (still a mistery)

[blank527]

Hi there,

I did some research on the Aleph P.
I found that out that the microcontroller is the hardest part.
The microcontroller controls the volume and input selection.
By optical sensors, the microcontroller can be adjusted.
It's like (I think) how a computer-mouse works.
If we could just replace this 87C750 (80C752) from Philips for a Pic programmable IC. I have done a search and I think it is possible with this kit:
http://www.velleman.be/downloads/0/Manual_K8045.pdf
http://www.velleman.be/Product.asp?lan=1&id=349182
It is actually an LCD controller, but if we program it for other use such as volume-control or input-selector.
It's like an cheap Pic-programmer.
I've seen other volume controllers on this site, my thought about that is, 8 steps volume.. that isn't a lott.
If it works, you could just buy the PCB from Kristijan and implement it.
The other IC's like 74HC573 are buffer IC's wich shouldn't be a problem.
Tell me if I'm wrong.

Greetzzz,
Remco Blankesteijn

 

[Kravchenko_Audio]

8 bit Volume control Without Micro

I think that if you go to the volume control thread in the Pass Labs section you will find that the 8 bit dac version of the volume control actually has 256 steps. This might be what you are looking for.

Mark

 

[Dane]

Yes, you can have more than one resistor "switched" at a time, and in parallel.
Something like this perhaps, unless I got the LSB/MSB backwards.

Decimal Binary Resistance (ohms)
1 1 0 0 0 0 0 0 0 8,060.0000
2 0 1 0 0 0 0 0 0 4,020.0000
3 1 1 0 0 0 0 0 0 2,682.2185
4 0 0 1 0 0 0 0 0 2,000.0000
5 1 0 1 0 0 0 0 0 1,602.3857
6 0 1 1 0 0 0 0 0 1,335.5482
7 1 1 1 0 0 0 0 0 1,145.7041
8 0 0 0 1 0 0 0 0 1,000.0000
9 1 0 0 1 0 0 0 0 889.6247
10 0 1 0 1 0 0 0 0 800.7968
11 1 1 0 1 0 0 0 0 728.4246
12 0 0 1 1 0 0 0 0 666.6667
13 1 0 1 1 0 0 0 0 615.7372
14 0 1 1 1 0 0 0 0 571.8350
15 1 1 1 1 0 0 0 0 533.9525
16 0 0 0 0 1 0 0 0 499.0000
(...)
233 1 0 0 1 0 1 1 1 34.0602
234 0 1 0 1 0 1 1 1 33.9162
235 1 1 0 1 0 1 1 1 33.7741
236 0 0 1 1 0 1 1 1 33.6296
237 1 0 1 1 0 1 1 1 33.4899
238 0 1 1 1 0 1 1 1 33.3506
239 1 1 1 1 0 1 1 1 33.2132
240 0 0 0 0 1 1 1 1 33.0691
241 1 0 0 0 1 1 1 1 32.9340
242 0 1 0 0 1 1 1 1 32.7993
243 1 1 0 0 1 1 1 1 32.6664
244 0 0 1 0 1 1 1 1 32.5312
245 1 0 1 0 1 1 1 1 32.4005
246 0 1 1 0 1 1 1 1 32.2701
247 1 1 1 0 1 1 1 1 32.1414
248 0 0 0 1 1 1 1 1 32.0106
249 1 0 0 1 1 1 1 1 31.8839
250 0 1 0 1 1 1 1 1 31.7577
251 1 1 0 1 1 1 1 1 31.6331
252 0 0 1 1 1 1 1 1 31.5063
253 1 0 1 1 1 1 1 1 31.3836
254 0 1 1 1 1 1 1 1 31.2613
255 1 1 1 1 1 1 1 1 31.1405

 

[blank527]

Hi,

Ok, but then how to implement a remote control?
With a Pic it is easier I think.

 

[Dane]

Yes, a microcontroller of some kind, an IR detector, and software to glue it together. A display if you want that also.

 

[till]

I made the ADC0804 version of this. It is quite easy to build and works good. Only it has one disadvantage, a lot of switching noise when you tune the volume. This is because during tuning there a moments with no realis closed then some closed etc. If you use the MC, this noise can be avoided by switching a relais closed that should be closed according to the value you read at the volume controll (optical, AD input etc) , wait a moment, than open a relais that should be opened and so on. So the switching isn´t that hard. (sorry language skills missing to use better words here)

btw. who needs remote? - sure this task is easy with a MC

 

[Klaus]

solution w/o SW must

I also - like Till - combined P1.0 with P1.7. I use from P1.0 the ADC0804 volume controll, but with 7bit. Good voltage supply for the ADC is a must. No SW programming necessary. The inputs are switched by simple mechanical 6 step-4 contact Elna-switch by hand. For the remote controll of volume, gain level (+6dB), inverse polarity and mute I found a discontinued old remote controller IC and build a simple device added by flipflops for switching function on/off. http://leute.server.de/peichl/fernbed/fernbed.htm (sorry, it is in German, but the schematic is clear...). Alternative solution would have been to buy a IR-remote controll system from e.g. Alps http://www.schuro.de/preisl-fernb.htm for a quite reasonable price of 85€. So, no SW at all, plug&play...

regards

Klaus

 

[ElectroNick]

Goedenavond Remco,

I'm building the BoSoZ. A remote is something i like very much. Therefore i'm puzzling how to use an Atmel ucontroller. A friend of mine started working with those things and he's pretty enthousiast about them.
It should be possible to use one for source selection and volume control. Then you wouldn't need an A/D convertor.

Last thing the atmel should do is controlling the red LED matrix display. (i like the Mark Levison look !!!)

Take a look at this . That's the goal

Grtz,
Nick

 

[mlloyd1]

pic based remote control solution ...

I like this one. It is flexible, easy to use and works well. It's not very expensive and I happen to have a few extra Sony universal remotes looking to be useful.

Of course, if you are one of those folks that likes doing your own coding, you may be disappointed

http://www.rentron.com/remote_control/IR-D14.htm

mlloyd1

 

[gogo]

>Hi,
>Ok, but then how to implement a remote control?
>With a Pic it is easier I think.

I will use ADC0804 (8 bit) with motorised potentiometer (from old receiver) and with old remote controll driving the pot. Think that this will be easyest way....

 

[ElectroNick]

You could use a pic controller to control a stepped attenuator with relays. 256 steps no problem. No worry about left/right signal level. I think it is as accurate as an expensive DACT stepped pot.

There are already some nice PCB layout posted her...

Grtz
Nick

 

[Ren]

Re: pic based remote control solution ...

I like this one. It is flexible, easy to use and works well. It's not very expensive and I happen to have a few extra Sony universal remotes looking to be useful.

mlloyd1,

That is a slick little device. Especially since it will source 25mA on each output pin up to 200mA total. So I started thinking that I could drive the relays for volume control / source switching on my BOSOZ directly from this chip (latching 5V types take ~ 8mA). But it looks like each output pin on this decoder chip just toggles.

So, I would still need to build some kind of up / down counter w\ binary output to keep track of the volume up / volume down pulses on D12 & D13, right? Or did I miss the point?

Also, I'd like to have some kind of volume control right on the front panel that would work in parallel with the the remote. That could be as simple as volume up / volume down buttons on the front panel. Any thoughts on how that could be done?
Thanks,

Ren

 

[ElectroNick]

How about a "Pass approved" blue display for the Aleph P ?

Grtz,
Nick

 

[JordanG]

Aleph P..

I'm doing an Aleph P volume control using a PIC and a remote control...

This is my attenuation board:

The 8-pin header at the bottom of the board goes to a logic/driver circuit.. In my case, an octal buffer and I2C 8-bit IO expander, tied to a PIC18F452. However, you could avoid the PIC and use an up/down counter circuit; the IR signal decoding might get messy though.

--Jordan

 

[ElectroNick]

Jordan,

those volume boards all look the same . I designed one too, can't see much diffrence.
But that pic-controller... did you get the IR part working already ?
I'm trying the same only with an Atmel processor. Maybe in combination with such a blue display, that would be

Could you post something like a flowchart or piece of code to clarify something to me. Programming is still a (great) mistery to me..

Grtz,
Nick

 

[guido]

Hi,

click on my www to get RC5 decoding routines for PIC.
State-machine in software, works very well!

Guido