100W Ultimate Fidelity Amplifier

Jump to Latest
N

Noise

Member
Joined 2005
viki_v2 said:
Sorry Sir. Could not understand anything. Only if some one could point out the formula for different voltages so I dont have to ask every time.
Click to expand...

Are you asking about how to find the DC voltage after rectification?

If that's the case, then it's easy. You take the AC voltage and multiply it with 1.41.

So your 24VAC transformer will give you around (24*1.41)= 33.8VDC, and your 30VAC transformer will give you around (30*1.41)= 42,3VDC.

Please remember that the voltage is not stabilized, it can and will vary depending on your input voltage from your mains sypply. And it will also be higher, when there's no load on the transformer.
So remember to add enough safety margin on your capacitors voltage limit. To be safe you might want to chose 50V caps for the 33.8VDC, and 63V caps for the 42.3VDC.
 
viki_v2

viki_v2

Member
Joined 2009
Noise said:
Are you asking about how to find the DC voltage after rectification?

If that's the case, then it's easy. You take the AC voltage and multiply it with 1.41.

So your 24VAC transformer will give you around (24*1.41)= 33.8VDC, and your 30VAC transformer will give you around (30*1.41)= 42,3VDC.

Please remember that the voltage is not stabilized, it can and will vary depending on your input voltage from your mains sypply. And it will also be higher, when there's no load on the transformer.
So remember to add enough safety margin on your capacitors voltage limit. To be safe you might want to chose 50V caps for the 33.8VDC, and 63V caps for the 42.3VDC.
Click to expand...

Sir, I am trying to understand the changes i need to make on FX100 psu + protect to make it work on above mentioned voltages or any voltage from 24 0 24 to 42 0 42.
 
C

cornelpopa

Member
Joined 2017
viki_v2 said:
Sir, I am trying to understand the changes i need to make on FX100 psu + protect to make it work on above mentioned voltages or any voltage from 24 0 24 to 42 0 42.
Click to expand...

Hi viki_v2

PSU Fx 100 does not provide adjustable feed voltage.
You can use PSU 10 for 30 V ac, but replaces Zenner 24v with 6V to have 24V to 42 V dc. The thread is big and I haven't PCB.
 

Attachments

  • FX100.pdf
    359.6 KB · Views: 319
  • APEX Regulated PSU-10.jpg
    APEX Regulated PSU-10.jpg
    259.4 KB · Views: 1,542
  • APEX Stereo Protect.JPG
    APEX Stereo Protect.JPG
    246.9 KB · Views: 1,486
  • apex psu-10 silk.jpg
    apex psu-10 silk.jpg
    704.5 KB · Views: 1,481
  • APEX Simple stereo protect.JPG
    APEX Simple stereo protect.JPG
    272.2 KB · Views: 1,405
prasi

prasi

Member
Joined 2014
sites.google.com/site/analogdesign1234/
Paid Member
avtech23 said:
Hi Prasi,

Wonder if you had a BoM available for your boards? I am starting to gather parts for another build.. :D
Click to expand...

Hello Avtech,
Here it is attached. I didnt have it, but I just prepared it in one go as a guideline for you. Please be careful in using it.
I havent included any part nos for 1/4W MFRs. I think those would be available in your parts bin.

If you find any corrections please post back here again for others.

regards
Prasi
 

Attachments

  • BOM-apex ax14_total new_2pairs_rev1_sch clean up.zip
    15.7 KB · Views: 480
S

shabusf

Member
Joined 2010
prasi said:
I have it shared here. You may download gerbers.

W61084ASN13_apex ax14_total new_2pairs_rev1- Share Project - PCBWay

let me know if its not convenient, I can post here as well.

regards
Prasi
Click to expand...

Hi Prasi,
Could you please let me know whether this board is tested or not. I would like to get the boards done from pcbway.com.

Also, I remember like somewhere in the thread it is mentioned like the bias transistor BD139 should be on the same heatsink where the power transistors are installed. Is that important for AX14?

Thank you for the support:)

Sha
 
prasi

prasi

Member
Joined 2014
sites.google.com/site/analogdesign1234/
Paid Member
Hello Sha,
I dont know if its tested or not. I am in the process of gathering parts for the build it (for quite some time now).
yes the bias transistor has to be on the main heatsink or on the o/p device.
If you see the mage of silk, it mentions to put the BD139 on the o/p device.

regards
Prasi

Edit: One member has built it, and it went up in smoke while doing some measurements , short somewhere I am guessing. He is building another channel.
 
Last edited:
C

chat72

Member
Joined 2012
prasi said:
Hello Sha,
I dont know if its tested or not. I am in the process of gathering parts for the build it (for quite some time now).
yes the bias transistor has to be on the main heatsink or on the o/p device.
If you see the mage of silk, it mentions to put the BD139 on the o/p device.

regards
Prasi

Edit: One member has built it, and it went up in smoke while doing some measurements , short somewhere I am guessing. He is building another channel.
Click to expand...

I'm the one who blew it but I don't think something wrong with the board. I have check the schematic with the board layout, I find nothing wrong.

It went into smoke because I short the circuit some where while trying to measure something on the board. The board is crowded so you must be careful when doing a measurement.

Now I'm in the process of building another one, I'll let you know.
 
S

shabusf

Member
Joined 2010
prasi said:
Hello Sha,
I dont know if its tested or not. I am in the process of gathering parts for the build it (for quite some time now).
yes the bias transistor has to be on the main heatsink or on the o/p device.
If you see the mage of silk, it mentions to put the BD139 on the o/p device.

regards
Prasi

Edit: One member has built it, and it went up in smoke while doing some measurements , short somewhere I am guessing. He is building another channel.
Click to expand...

Thank you Prasi for the update. I missed the note regarding bias transistor placement which you have kept. Will take care of that while populating.


Thank you
Sha
 
S

shabusf

Member
Joined 2010
chat72 said:
I'm the one who blew it but I don't think something wrong with the board. I have check the schematic with the board layout, I find nothing wrong.

It went into smoke because I short the circuit some where while trying to measure something on the board. The board is crowded so you must be careful when doing a measurement.

Now I'm in the process of building another one, I'll let you know.
Click to expand...

Thank you Chat72. Please let me know once you are done with your second board :) . I ll put the PCB order on hold for now.

Thank you
Sha
 
You must log in or register to reply here.
Top Bottom