how to find out balanced and unbalanced pulsars ?

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nebelfuerst
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how to find out balanced and unbalanced pulsars ?

Post by nebelfuerst »

Hi,

I have about 6 pulsars. Some came with balanced and some with unbalanced connectors.

As the connector at the pulsar looks identical, I'd like to ask, whether is makes any difference if I plug the unbalanced wires into a balanced card ? ( Or vice versa.)
( I threw all wires into one box, so you know, where my mess originates ;-)

Is there any way to see at the pulsar itsself, whether its balanced or unbalanced ?

bye
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Neutron
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Re: how to find out balanced and unbalanced pulsars ?

Post by Neutron »

they probably use different circuit on board but its hard to tell with tiny surface mount components.
do you have keys for them? if you do you could use a non balanced wiring, and try each one with the same project. the loud ones would be the "pro" balanced cards.

that way you can also test to make sure you dont have any dead ones.
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kylie
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Re: how to find out balanced and unbalanced pulsars ?

Post by kylie »

I somehow remember someone saying there is an additional chip on the I/O plate maintaining the AES connection, but looking at the boards would incorporate removing all I/O boards from all pulsars to see the difference. I don't know whether S|C keep a record on what I/O board was initially sold with the dsp card if you feed them your hw serials, but it would be worth a try...
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Fluxpod
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Re: how to find out balanced and unbalanced pulsars ?

Post by Fluxpod »

For Pulsar 1 cards its easy.There is a small chip in a socket near the connector to the cable whip which tells you that this is the "pro" version balanced with aes-ebu.For pulsar2/pro cards with seperate i/o plate...no idea,maybe there is 1 of those small chips on the plate aswell but i am not sure that it is in a socket and not soldered on.
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capacitor
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Re: how to find out balanced and unbalanced pulsars ?

Post by capacitor »

I think this is the chip (marked 1601 B9844 on this one)
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capacitor
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Re: how to find out balanced and unbalanced pulsars ?

Post by capacitor »

Plus/balanced i/o plate, 1601 B0600 (can anyone recognize the manufacturer's logo? I'm stumped atp)

Edit: plugged a classic whip into a Pulsar I balanced i/o card, with no ill effects. The outputs were noticeably hotter (+4dbu), inputs passed audio & digital i/o worked somewhat. Did not test MIDI.
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Neutron
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Re: how to find out balanced and unbalanced pulsars ?

Post by Neutron »

wow a 10 pin IC, you don't see that every day.
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Re: how to find out balanced and unbalanced pulsars ?

Post by Fluxpod »

Neutron wrote:wow a 10 pin IC, you don't see that every day.
Its 8 pins :wink: And the one on my pulsar 1 is only 4 pins if i remember correctly.
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capacitor
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Re: how to find out balanced and unbalanced pulsars ?

Post by capacitor »

I can't look at the P1 anymore but the Plus plate's IC has 10 legs (just double checked). Flux, are two of the legs duplicated internally?

If you know what this chip is, give up the goods! :P
Fluxpod
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Re: how to find out balanced and unbalanced pulsars ?

Post by Fluxpod »

capacitor wrote:I can't look at the P1 anymore but the Plus plate's IC has 10 legs (just double checked). Flux, are two of the legs duplicated internally?

If you know what this chip is, give up the goods! :P
I was talking about the chip on the pic thats 8 pins on that pulsar 1.On my pulsar 1 i am pretty sure the chip is in the same spot but just has 4 pins each side.I would guess its a simple op amp to bring the signal to +4.
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Neutron
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Re: how to find out balanced and unbalanced pulsars ?

Post by Neutron »

Probably a line driver or something like that
sometimes DSL drivers could be used for audio as well. then the extra legs might have been for current feedback or something.

but i couldnt even find that logo on my favorite IC logo looking up page.

http://www.advanced-tech.com/ic_logos/ic_logos.htm

and its kind of fat and beefy it might not even be an IC, maybe a miniature transformer or something.

and bringing the output up to +4 from a low signal would not be a very "pro" way to do it:) it has to be a bipolar balanced output, and depending on the DAC, it could already be bipolar on the DACs output.

anyway enough electronics boffinry for now :)
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Re: how to find out balanced and unbalanced pulsars ?

Post by siriusbliss »

It looks Chinese.

Also looks like it's from some old stockroom somewhere. :P

Yes, maybe an opamp, or driver chip. If corner pins are power/gnd, then my assumption is that it is a power driver, due to it's location down near the din connector.

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Neutron
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Re: how to find out balanced and unbalanced pulsars ?

Post by Neutron »

siriusbliss wrote:It looks Chinese.
nah if it was Chinese it would say "national semiconductor" or "texas instruments" in badly silk screened printing and everyone's pulsar pros would be dead. :D
nebelfuerst
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Re: how to find out balanced and unbalanced pulsars ?

Post by nebelfuerst »

Thank you very much for the perfect replies.
Now I can match my wires with the pulsars again ;-)
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capacitor
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Re: how to find out balanced and unbalanced pulsars ?

Post by capacitor »

Update: found the datasheet for the 10 pin chip, by chance while seeking an 8 channel sample&hold circuit.

Note: middle pins unused
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Newport (now C&D Tech) 1601 dual isolation transformer pack
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