It sort of is an illusion because it's at an angle, plus the depth.
Anyway, it's at least as big or bigger than the heat sink on post #69.
It is machined for TO-03.
I just found out that participating Home Depot stores rent FLIR cameras, so I'll give that a try later. Thanks for the info.
Does open up unusual possibilites to cool the device .
- Fashion dry ice into 1 inch circular pillars to fit in the open well and contact the base.
- Drip de-ionized and distilled water in the well at a certain rate to a stable level without its overflow.
Just in the case you are not familiar with these things, imaging shiny metal objects like 2sk82s, 28s or whatever gives improper temp readings due to low emisivity. Looking at TO3P (plastic) packages is 97% correct but shinny metal will need to be coated with something to get correct temp readings. I used to use white out correction fluid but, I've been using Cerameque thermal compund lately. It's basically that you get reflectivity from the shinny surface instead of emisivity. Generally you will see black or low temp indications on something you know is hot if you've got this problem. You can even get reflected emisive energy from a shinny object. Different surfaces have a different emisivity. You can probably google and find a chart, I couldn't find mine. Shinny metal is the worst offender 😀
Don't forget to post pics here.
Thoughts about amplifier gain:
If I've understood correctly in theory the gain of the amp is ( current source in parallel with speaker ) / ( 1/0.4 )
And it is because of this that gain increases with the inductor since the inductor has much higher resistance? Though not massively since the 8 ohm speaker still limits the gain.
So if we simplify and assume that the inductor has a resistance of 100 since we won't use the amp for bass the gain with an 8 ohm speaker would be close to 3 or 9.6 dB if I remember my math correctly.
But that is not what I wonder... what I wonder is that does this mean that if I use an 18 ohm speaker instead the gain jumps up to 6.1, or 15.6 dB?
If I've understood correctly in theory the gain of the amp is ( current source in parallel with speaker ) / ( 1/0.4 )
And it is because of this that gain increases with the inductor since the inductor has much higher resistance? Though not massively since the 8 ohm speaker still limits the gain.
So if we simplify and assume that the inductor has a resistance of 100 since we won't use the amp for bass the gain with an 8 ohm speaker would be close to 3 or 9.6 dB if I remember my math correctly.
But that is not what I wonder... what I wonder is that does this mean that if I use an 18 ohm speaker instead the gain jumps up to 6.1, or 15.6 dB?
choke means inductive storage
think twice output voltage , comparing to PSU
meaning - when having resistive or CCS based load part of amp , output voltage amplitude can go just between rails
when having choke - it can go almost twice that
roughly
voltage , same as ground , is elastic term
think twice output voltage , comparing to PSU
meaning - when having resistive or CCS based load part of amp , output voltage amplitude can go just between rails
when having choke - it can go almost twice that
roughly
voltage , same as ground , is elastic term
Hi Michael,
I was wondering how to test for gate leakage of your final circuit for the inductor version. If the input cap needs to be there what is the lowest value it could be without affecting circuit if possible.
Thanks,
Eric
You could measure the voltage across Rin (R1) and figure the current. Most of my 2SK82 examples have been a couple of microamps or less.
Does you preamp have AC-coupled outputs?
Does you preamp have AC-coupled outputs?
Hi Michael,
At the moment it is the LightSpeed but eventually I will be using the my B1 which is AC coupled. Oh! I think I see what your getting at. So I won't need the input caps for the L'Amp if my preamp has AC coupled outputs.
At the moment it is the LightSpeed but eventually I will be using the my B1 which is AC coupled. Oh! I think I see what your getting at. So I won't need the input caps for the L'Amp if my preamp has AC coupled outputs.
Perhaps you won't. Try it. But you'll need a cap in the chain somewhere since the input will not be sitting at or near 0V in that particular case.
Any objections to using a pair of CL-30s on the primarys to protect againt in-rush current? Using seperate transformers for main circuit power and bias circuit.
thanks
Vince
thanks
Vince
Here is my SIT Parafeed hybrid power amp manifested in matter.
There are two monoblocks...
There are two monoblocks...
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