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My RF controled PGA2320 MiniVol and ch selector

Luxman Amplifiers India

quad

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(I also posted this on diyaudio)

I got a lovely MiniVol board with the PGA2320 chip driven by a AVR microcontroller from diyaudio member.
The minivol provides vol up/down and mute, controlled by push switches or a rotary encoder.
The MiniVol is described here -

MiniVol PGA2320 Volume Control - error404's Audio DIY Endeavours

I also wanted a channel selector. So I rigged up a small
circuit around a CD4017 to step through the channels.
The DPDT relays are driven via 2N2222s.

To control everything, I got a cheap 4 Channel RF controlled switch on ebay. The receiver has a couple of
jumpers to choose the mode - toggle, latch or momentary.
I used the momentary mode. The 4 channels are used
for Vol Up, Vol Down, Mute and Channel select.
The open RF receiver/relay board, and the remote alongside are visible in one of the pics.

The PGA2320 is a really nice volume control chip, sweet
and transparent.
I wanted an appropriate box, so I put
the whole thing in a Ferrero Rocher chocolate box!

Eagle files for the channel select logic are in my diyaudio post.

Prasad
 
Last edited:

soundsgreat

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Hi,

Prasad Congrats on the newly developed thing:) !! I must say you must have gone through some pain in making such a thing,so Kudos to you :clapping: !!

Some pointers if you don't mind ;)!

1) although I guess this seems very good but I'd request you to increase the distance of trafo (seems bit too close to main circuit) or shield it appropriately

2) Please Please use some high quality wires as the ones used will not (ribbon wires are ok for testing but not actual unit to be used)

3) Usage of EMI/RFI Filter at the main socket will give it some advantages since microcontrollers are very sensitive devices (offcourse you know this but still....;) )

Well please consider the above,Hope to see the results and first impressions on the overall thing soon from you !

I myself Am into something like that,though I choose to do a Stepped Attenuator with LCD display and such ! Working on it using ATMEL chip !

Also Prasad could you please give me your E-Mail ID so that I can send a mail to you ?? if you remember you had posted in thread bout me working another member to develop a Mid-Bass driver,Well I have on my own and Am currently seeking some feedback on the same ! can send you all the details of it should you be interested to take a look at it !

Regards.
 

kaushik

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A LCD meter will be cool
3423127762_6d1d93867e_o.jpg


As in the thread Arduino Forum - any pga2310 volume control examples?
 

spirovious

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Apr 10, 2008
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Its gr8 to watch DIY products.
I wish similar more & easy getting in India.
 

quad

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Messages
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Points
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Location
Hyderabad
Sreekanth,

Thanks for the feedback. This is definitely in the nature
of a quick-n-dirty proto, mostly to try out the MiniVol.
I will rebuild it properly later, on the PCB I laid out in Eagle.
Trafo shielding (may use a small toroid) and a RF filtered
IEC inlet etc will be taken care then.

I should mention that the audio signal path is really
short, and the cables are shielded. The digital and
audio grounds are properly separated in the
Minivol, as per the PGA datasheet.
This thing is absolutely noise or hum free even now.

The ribbon cable is on the digital side only -
for the Vol up/dn and mute controls, which are
connected to the remote relay board. They just pull
the relevant pin on the AVR to digital ground when
the appropriate remote button is pressed.

Stepped attenuator would be lovely. I saw your query
in the DIYA group buy for Danzup's pre.

Prasad
 

soundsgreat

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Sep 23, 2007
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Hi,

Sreekanth,

Thanks for the feedback. This is definitely in the nature
of a quick-n-dirty proto, mostly to try out the MiniVol.
I will rebuild it properly later, on the PCB I laid out in Eagle.
Trafo shielding (may use a small toroid) and a RF filtered
IEC inlet etc will be taken care then.

I should mention that the audio signal path is really
short, and the cables are shielded. The digital and
audio grounds are properly separated in the
Minivol, as per the PGA datasheet.
This thing is absolutely noise or hum free even now.

The ribbon cable is on the digital side only -
for the Vol up/dn and mute controls, which are
connected to the remote relay board. They just pull
the relevant pin on the AVR to digital ground when
the appropriate remote button is pressed.

Stepped attenuator would be lovely. I saw your query
in the DIYA group buy for Danzup's pre.

Prasad Am glad to read the reply !! just as I had guessed it,its a rough proto :)!!

Your proposed rework idea is very good, so you design your own PCB's thats excellent !! Perhaps later once all is settled I'd be interested to take a sample for a test drive ;) !!

Yes I did try to get it from him,as you may read the shipping cost and such makes the whole deal very sore !! for the same amount of money I can get atleast 3 sets done locally :sad:!! so left that Idea !

Regards.
 
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