Not that 45C is anything to those big Mosfets. No problem for other bit faraway parts either unless housing it in a small non ventilated box.
That is the plan but I'll probably run it for a couple weeks bare while I sort out the case.
I figured 45C was ok and I appreciate your advise on it - as usual I'm learning, I was suprised at how different the IR emissivity is for black anodized vs non-anodized aluminum.
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You need to desolder them for changing position though. They need slip legs under the board's edges with pronged up ends. Like when mounting power amp boards flat against sinks.
Yes that is the plan, no problem desoldering - I think that is the one thing I'm most accustom to since I'm always making mistakes.
I have an IR thermometer with adjustable emissivity and I never quite found well repeatable setting and distance formulas for various things. Especially for shiny ones. If its critical I still use the Fluke's thermocouple probe in the end to make sure. 😀
That's exactly what I ended up doing, I used a directly attached thermocouple and then messed around with the IR emissivity setting until they agreed. I ended up at .24 emissivity for the bare aluminum and the default emissivity is usually .95 on most handheld IR guns.
Sounds good - I'd be curious to see what you find.
I read through all the Mezmerize, Hypnotize and DCB1 threads and I think I'm slowly getting a little bit of a grasp of the shunt circuit 🙂 - ingenious.
10~20cm, my IR gun has two laser LEDs to show the diameter of the sensor circle. It's really finicky and I wouldn't trust it without a direct thermocouple comparison.
The UNI looks like a good value. Mine is a Klein IR5, available at HomeDepot here in the US for $60, seems to be pretty well made.
I am interesting to build a Mezmerize B1 Buffer. I have a relay based attenuator of 10K. It is lower than suggested 20K. Can I use it? What could be the disadvantage to use it? The output impedance of my DAC is 50 ohms, and the input impedance of my power amp is 10K ohms (only balance input which is equipped on the active studio monitor)
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Technically acceptable. Maybe expect little more brilliant sound than DCB1's usual tone if with 10K. Because DCB1 has very wide bandwidth and the 10K lets it more free than with the usual 20K. But details of tone can also be property of the attenuator quality. More so than the bandwidth impact discussion.
Hi Salas,
I was thinking about adding 2 buffer stages on the one B1 power supply to 'bracket' my Linkwitz Transform circuit (+10dB @ 30Hz with Q = 0.71) - would there be any complications like interference between the 2 jfet stages about doing this? I have the usual 7mA range jfets.
I was thinking about adding 2 buffer stages on the one B1 power supply to 'bracket' my Linkwitz Transform circuit (+10dB @ 30Hz with Q = 0.71) - would there be any complications like interference between the 2 jfet stages about doing this? I have the usual 7mA range jfets.
Oh, this is to feed my bass power amp after 12dB electronic Xover (Pass 6-24) at about 150Hz (not finalized yet), amp input Z is 20kR and the IC for the Linc Transform is to be the usual 2134, etc.
The DCB1's shunt PSU has big reserve for such small consumption additions as it is usually set with a 150mA-200mA current limit. Just take the usual shorter possible rail cable runs and local decoupling precautions to and at the clients. Prefer 10uF tantalum local decoupling if ever needed. They are easier than film caps on how remotely seen by this reg. You can check rail stability against oscillation with a CRO or DSO when AC coupled to its probe. Vertical 10mV and sweep horizontally from 1mS to fastest.
Thanks very much for the info - will build the L/Transform circuitry adjacent to the DCB1 and proceed with checks. Thanks again