M2 for me!
that amp is best ever!!
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Which brings to the (off-topic) question: is there (or ever been) an M1? 😕
Which brings to the (off-topic) question: is there (or ever been) an M1?
Have a look at the First Watt product table over on firstwatt.com .
_
Exactly looking at that table I noticed the missing piece (the question did not arise for the J2 since there is an F1J... I am guessing) 🙂
But if I am allowed to (one last) off-topic, then this is the only M1 that comes to my mind. 😎
I use the vanilla 5W-30 in my new vehicle. I don't think it's as good as it used to be though after they tinkered with the formula...is there (or ever been) an M1? 😕
This is the one shipped with the back panel kit from the store.
https://www.mouser.com/ProductDetail/Schurter/4304.6090?qs=SkYLJkUpGh1O7%2BOWjtJ4SQ==
https://www.mouser.com/ProductDetail/Schurter/4304.6090?qs=SkYLJkUpGh1O7%2BOWjtJ4SQ==
I found a 20V dual primary transformer collecting dust, can I use this as a drop in without any further mods ot the PS or the amp?
Regards, Vinay
Regards, Vinay
I found a 20V dual primary transformer collecting dust
If you have a 20V dual secondary transformer, you may use that for the F5M. Your rectified voltage will be around 27-28V DC which is still fine even with the JFET input stage. I am assuming you have 120V primaries available to connect to your AC mains.
Best,
Anand.
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Yes to all.If you have a 20V dual secondary transformer, you may use that for the F5M. Your rectified voltage will be around 27-28V DC which is still fine even with the JFET input stage. I am assuming you have 120V primaries available to connect to your AC line.
Best,
Anand.
Your rectified voltage
with A Class amp as load, and usual rectifier/filter arragement, count on 1.25 multiplying factor
18Vac resulting in usual 22V5dc ........ 2 volts more ............ 24V5dc
leeway is Volt or so
in any case, 20Vac sec calls for 35Vdc caps
Thanks, I think that I ended up using that for my A Jzm.This is the one shipped with the back panel kit from the store.
Speaking of Caps, I have some old school beer can caps( 47-68k uF, 50 or more V) that I could spruce up, tho would need to wired to the PS boards as they are screw terminals.....or should I just go with the modern ones recommended for these projects to keep it simple and compliant with the designs.in any case, 20Vac sec calls for 35Vdc caps
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A volt or two between friends 😉 . Forgot about the high bias Class A load, and smaller VA donuts, silly meleeway is Volt or so

I always end up using at least 10V DC more for electrolytic caps due to variation of AC mains voltage (119-123 at my home).
Best,
Anand.
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voltage rating aside, is using large capacitance better of just stick to the as designed PS?A volt or two between friends 😉 . Forgot about the high bias Class A load, silly me.
I always end up using at least 10V DC more for electrolytic caps due to variation of AC mains voltage (119-123 at my home).
Best,
Anand.
Regards, Vinay
You can use larger capacitance up to a point. Just remember the inrush current is more (which taxes your thermistor, power switch, etc…). For more details and calculations, see my post here. If this is a new build or you are a new builder, suggest sticking with the original design so your maiden voyage is without fireworks. I personally try to limit as much ptp wiring as possible to minimize points of failure.
Best,
Anand.
Best,
Anand.
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