Building the ultimate NOS DAC using TDA1541A

one more picture

autonomy with full battery charge
for one month
in yellow the batteries desconecsion relays
An externally hosted image should be here but it was not working when we last tested it.

to the right of the image on the top cover
volume control potentiometer 100 ohm for r-i / v converter
teflon capacitor 100k
J79 battery powered amplifier
An externally hosted image should be here but it was not working when we last tested it.
 
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I want to supose that you are not using +7v, -7v and -16v directly to the TDA, it's a little bit dangerous, yo ucan damage it. If you paint the border of the CD's in black with a permanent marker, you'll still hear the TDA even better, with a lot more of detail and better image. the top cover has 2 black round things, what are these?, are they some battery? What VCXO do you use?, it looks interesting.
 
I want to supose that you are not using +7v, -7v and -16v directly to the TDA, it's a little bit dangerous, yo ucan damage it.
If you paint the border of the CD's in black with a permanent marker, you'll still hear the TDA even better, with a lot more of detail and better image. the top cover has 2 black round things, what are these?, are they some battery?
What VCXO do you use?, it looks interesting.
I use series resistance
to reduce the voltage
black round
are wire raund potentiometers 100 ohm
to control the volume
act as r - i / v converter
sorry is a TCXO
Temperature Compensated Crystal Oscillator
Ultra Vanguard Golden precision TCXO, 0.3ppm 11.2896MHz
buy it on ebay
 
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Thank you for your answer. Only one tip, try to obtain a lower phase noise oscillator, in this case I think that it's more important the phase noise than the precision. -125bdc/hz is not bad, but if you can low it some tens of db, let's say down to -160dbc/hz, you will be very surprised with the results, believe me. On the web there are some schematics you can download and use. to build a very good clock oscillator.

Kind regards,
 
Hi roger57



These are custom made, multi-segment air chokes (non tunable). They consist of two dual half core formers glued together (intended for use with ferrite pot cores). Turns are equally divided over these 2 formers (4 x 50 windings). These chokes are then screened using a brass IF transformer screen.

The photograph shows an early prototype.
John,
I see some strange values for the clock crystal here in the picture: 11.2063 Mhz.
226072d1307404021-building-ultimate-nos-dac-using-tda1541a-airchokes.jpg

Looking on the net gives no clue. Just curious!
 
spanish is the second language speaked in all the world

Please switch to English, or German ;-)

This is only a little communication between members from Spain. I easy you translate to German or English.
The interest is the mother of the action and for a couple of words.
Thanks Friend
El español es la segunda lengua mas hablada del mundo, ésta es una pequeña comunicación entre miembros de España. Es muy fácil para tí traducir al Alemán o al Inglés.
El interés es la madre de la acción y, por un par de palabras que no molestan a nadie.
Gracias Amigo
Esteban Bikic
 
yes but ernesternest call to switch to german too

Forum rules are clear: post need to be in english. Otherwise it will be a mess here.

Just suppose I would start posting in the the second largest world language after spanish (dutch) :D
And everybody know that the english is the real language in this Forum.
But for a couple of words in our spanish is a good new because is not common to find Spanish speakers here.
Best Regards
Esteban Bikic
 
Do you still have S2 ?

hi all,

for update only, if any diyers like to build john's ultimate design 1541a pls email for me about the same date code chips.

Today I check my stock of 1541a chips. still had some 88~91 date code can match 8~16 pcs same date code & same s/n.

BTW, assistance by peter. I can get the good price of 1541a double crown 1541AS2.

now will USD 80 per chip. include all charge, I will use regmail post to all diyers. Over 2 chips I will suggest use insurance parcel. This price was almost same as three years before.

thx

thomas

I am eading the article of TDA1541, and asking if is possible to get from you double crown TDA1541.
Best Regards
Esteban Bikic
dady@comodoro.com
Spain