Great job, fmmech_24! You're going to have a lot of fun with your HPA design!
You might want to experiment with different bias voltages and currents than the standard Noir, since your HPA will operate on a lower supply voltage than Noir. Different supply, different optimum bias point.
The IRF510 in your supply smoother, has a fairly large gate-to-source voltage drop. Thus the supply smoother has a fairly large input-to-output voltage drop, perhaps on the order of 4.0 or 4.5 volts.
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You might want to experiment with different bias voltages and currents than the standard Noir, since your HPA will operate on a lower supply voltage than Noir. Different supply, different optimum bias point.
The IRF510 in your supply smoother, has a fairly large gate-to-source voltage drop. Thus the supply smoother has a fairly large input-to-output voltage drop, perhaps on the order of 4.0 or 4.5 volts.
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Attachments
I have ordered the items in the Mouser basket, save 2 items as these weren't in stock.
For the Alps (delivery expected Februari 2020) I chose as temporary replacement:
1688-RK16312A0B85
RK16312A0B85
ALPS Potentiometers
And for the Littelfuse I chose:
650-RXEF050-2
RXEF050-2
Littelfuse Resettable Fuses - PPTC
If there are better alternatives at Mouser, please advise, for other builders.
For the Alps (delivery expected Februari 2020) I chose as temporary replacement:
1688-RK16312A0B85
RK16312A0B85
ALPS Potentiometers
And for the Littelfuse I chose:
650-RXEF050-2
RXEF050-2
Littelfuse Resettable Fuses - PPTC
If there are better alternatives at Mouser, please advise, for other builders.
PjVervoorn: those look like good choices. US and Canada buyers can also buy the ALPS Blue Velvet potentiometers from Parts Express (here is a LINK), maybe they will also sell to customers in Thailand (?). And of course eBay sells lots and lots of Blue Velvet pots, we just don't know whether they are counterfeit or genuine.
mark johnson,..thank you for your work!
This is my Prototype, based on your T2/Noir..
My MAN I love when gerbers are below 10cm x 10cm
The ferrite core is out of stock at Mouser. Any easy replacement?
Since you're in the US, the best idea is probably to just buy it from DigiKey (LINK).
Maybe the second best idea is to buy Mouser part number 710-74270035 , keeping in mind that its diameter is much larger than the Laird bead which the Noir PCB is designed to fit. I expect it might be a little tricky to thread a plastic cable tie through the mounting holes on the PCB, encircling and securing such a wide core. But you may prefer this kind of challenge, rather than placing a DigiKey order. Extra long (8" , 200mm) zip ties might be useful here since they allow you to have plenty of "slack" above and below the board, and yet be able to mate the two ends, as you're positioning the coil and gradually tightening the zip tie. Amazon Link
I used this one from fair-rite, which had very similar specs to the original (both physically and electrically) and did the job just fine for me:
https://www.newark.com/fair-rite/26...5023002&ddkey=https:en-US/Element14_US/search
They have stock for about 50c US.
https://www.newark.com/fair-rite/26...5023002&ddkey=https:en-US/Element14_US/search
They have stock for about 50c US.
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