GOLDSCAN 5 SCHEMATIC QUESTION

[Geo]

Here are the files GS5 of the first part and the audio, in DipTrace format for those who want to modify them.
Jose[ATTACH]41072[/ATTACH][ATTACH]41073[/ATTACH]

Can you post the file as jpg type because i can't open them???

Thank you.

[daverave]

the 1st amp NE5534 should be the AP version which is low noise type.

[Altra]

Jose, Thank you for the files. I'll try to make a new one for the TDi

[Jose]

If you guys want to make an accurate schematic. I suggest we do it in diptrace. That way a few of us can make the changes before making public a final version. I did my drawings in a old version Orcad capture and it's not easy to go back and renumber parts. If Jose can send me his GS5 diptrace file it will save me a lot of time. I don't want to post multiple corrected schematics like so many other threads on this forum.

For frontend diodes many people use BAV99's they are fast and have a low capacitance.

Here are the files GS5 of the first part and the audio, in DipTrace format for those who want to modify them.
Josex2.rarGS45 3.rar

[Altra]

If you guys want to make an accurate schematic. I suggest we do it in diptrace. That way a few of us can make the changes before making public a final version. I did my drawings in a old version Orcad capture and it's not easy to go back and renumber parts. If Jose can send me his GS5 diptrace file it will save me a lot of time. I don't want to post multiple corrected schematics like so many other threads on this forum.

For frontend diodes many people use BAV99's they are fast and have a low capacitance.

[Orbit]

Only the diode is missing, what are you blaming? Diodes are not critical !

[eclipse]

Here is a link of 1N4149. Use only reputable sources (Farnell, Mouser, Digikey, RS, etc.).
Those diodes are rigid as they can come. I'm on my ~300 diode of these (3rd bag of 100s - not even one failed diode - I don't even measure them like I used to, before soldering).

[Idefix]

Hi..
Looking more closely at the specs, you are right. SS20 is not the good choice.. 1N4148 is about some pf against some hundred pf..

[6666]

1N4149, Thanks have ordered some.

[eclipse]

Yes , 2 diodes , it is half current in each, so it is more safe. And the voltage is also lower, because of the curve V/I of the diodes.
Let s try a SS22 , it is a schottky , half the voltage of silicium .

1n4148 has far less capacitance which you'd want for those diodes. Sticking to 2x or 3x configuration of 1n4148 is best.
I buy packs of x100 1N4149 (fairchild/on) from mouser which are rated 500mA / 4A continuous current.
After I started using those I've never had a deffective piece which happened all the time with cheaper alternatives if they are used on the edge of their specification, sometimes even 1/2 of that would make them pop.

[eclipse]

Eclipse is correct about the integrator inputs reversed. The integrator is a TL062, the next 4 amps same page are a quad lt1114. The audio gain stage is a LT1112. A quad TL064 is used for the absolute amplifier with one of the amps unused. I drew this for reference not to clone. If people find something they question circle it on the schematic and post. I will try to verify.

Altra also the first preamp stage should be inverting, so you need to reverse PIN2 and PIN3 (NE5534).
Also look at the power supply pins - those are mismatched (PIN4 / PIN7) (NE5534, AD8065)

[dbanner]

I noticed this on TDI pro proto schematic. I think maybe wrong?

[Idefix]

Yes , 2 diodes , it is half current in each, so it is more safe. And the voltage is also lower, because of the curve V/I of the diodes.
Let s try a SS22 , it is a schottky , half the voltage of silicium .

[6666]

6666 : the diodes: also have a look on The Stuart PI, and his comments about the diode. He uses a BY407A.

Thanks for the info, now that I zoom in to see the part numbers on the Stuart PI, I can see he used a BY407A, good idea, will try this in future,
I figured the 2 diodes in parallel on the GS5 was for some voltage/current load shareing stress relief .

[Idefix]

6666 : the diodes: also have a look on The Stuart PI, and his comments about the diode. He uses a BY407A.