my amp pcbs are all applicable to UMS, while my HA! pcbs are applicable to Modushop base plate - hole raster being 10mm
PSU is up and running, please note the small blue led 😀
No smoke, of course
No smoke, of course
Not exactly for this amp, but maybe for all of our 25w amps: I have "high performance" heatsinks with 0.3K/w @300w, 300 mm long, 100 mm high, the fins are 85 mm long. Could they be used for our amps, one per channel?
Thanks in advance!
Thanks in advance!
one per side, just right about for regular FW format
say, no more than 100W of heat, rather cozy for 80W
mentioned 300W, who knows what criteria was that
say, no more than 100W of heat, rather cozy for 80W
mentioned 300W, who knows what criteria was that
Ok, thanks!
...and... one channel in on 😀
Rails under load @+/-23.6v, DC offset 21mV.
But I can't bias higher than 165 mV across 0.11R, which means 1,45A 🤔
I let it cooke now for a while, but this values are stable since 20 minutes.
...and... one channel in on 😀
Rails under load @+/-23.6v, DC offset 21mV.
But I can't bias higher than 165 mV across 0.11R, which means 1,45A 🤔
I let it cooke now for a while, but this values are stable since 20 minutes.
DC offset 10mV, great, Iq is still @1,45A, can't adjust higher.
I mean it's fine, but the amp can't develop big heat
The heatsink is hot, but I can leave my hand on for a long time.
Edit: in the max ohmic position of the Iq pot at the start there was 59 mV across the 0.11R group.
I mean it's fine, but the amp can't develop big heat
The heatsink is hot, but I can leave my hand on for a long time.
Edit: in the max ohmic position of the Iq pot at the start there was 59 mV across the 0.11R group.
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change level shifter resistor to lower value
100R or 82R
back down with Iq prior to change
change
re-set
100R or 82R
back down with Iq prior to change
change
re-set
another way is to decrease value of R116, first lower standard value
so, 910R or 820R
though, if you give me present gate voltages of M101 and M102 - both ref to output node, I can give you exact/best recipe
so, 910R or 820R
though, if you give me present gate voltages of M101 and M102 - both ref to output node, I can give you exact/best recipe
Thanks MZM - looking at this schematics shows what the problem is.
I'm working with the schematics in your post #7 https://www.diyaudio.com/community/threads/scryer-or-how-f8-met-mighty-sissysit.388550/post-7078144 where the value of R116 is 1.3k instead of 1k in this new schematics 🤪
So I will simply change to 1k and I'm sure it will work and heat properly
I'm working with the schematics in your post #7 https://www.diyaudio.com/community/threads/scryer-or-how-f8-met-mighty-sissysit.388550/post-7078144 where the value of R116 is 1.3k instead of 1k in this new schematics 🤪
So I will simply change to 1k and I'm sure it will work and heat properly
there is a link in post #1, pointing to final schm
always check my posts #1, who knows what new edit is waiting there
always check my posts #1, who knows what new edit is waiting there
Okay, the changes are (but please correct me if I'm wrong):
R116 - 1k (was 1.3k)
R130, 131 - 6k8 (was 4k7 - smd-parts, I suppose there are the correct ones on the board?)
C109 - 100p (was 120p - smd-part, so same as before?)
So in fact I only have to change R116?
R116 - 1k (was 1.3k)
R130, 131 - 6k8 (was 4k7 - smd-parts, I suppose there are the correct ones on the board?)
C109 - 100p (was 120p - smd-part, so same as before?)
So in fact I only have to change R116?
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just change R116 to 1K
gimme gate voltages of said mosfets, now or after the change, noting set Iq
gimme gate voltages of said mosfets, now or after the change, noting set Iq