Search found 70 matches

by ilya
Tue Jun 23, 2020 5:37 am
Forum: Pro Audio Design
Topic: Method for testing thermal coupling
Replies: 9
Views: 563

Re: Method for testing thermal coupling

Can you tell more about what you want to thermal couple and why ? JR nailed it. Yes, that's for coupling transistors in LTP, current mirrors etc. Maybe I'll get to the discrete VCA (JR will probably laugh at that). It's still not clear to me how to measure the amount of tracking between the coupled...
by ilya
Sun Jun 21, 2020 5:54 am
Forum: Pro Audio Design
Topic: Method for testing thermal coupling
Replies: 9
Views: 563

Re: Method for testing thermal coupling

Thanks!
Sometimes the correct search phrase is important. I tried searching for "thermal coupling" and got no useful information. That's why I posted here.
I'll check out the Netional stuff and see what the "thermal resistance" brings.
by ilya
Sat Jun 20, 2020 6:13 pm
Forum: Pro Audio Design
Topic: Method for testing thermal coupling
Replies: 9
Views: 563

Method for testing thermal coupling

I'm making a device that requires thermal coupling of transistors. I can couple devices mechanically in several ways. I'd like to test and find out which of the coupling method works best.
Is there any recommended procedure or, maybe, paper that describes how to measure such a thing?
by ilya
Mon Sep 03, 2018 5:36 pm
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Re: Negative impedance converter reactance

JR. wrote:
Mon Sep 03, 2018 5:16 pm
So if I google "the bridged-t equalizer" I'll get your schematic?

I'm tapping out now..

JR
Sorry, didn't realize you wanted the schematic. I thought what I posted was sufficient.
I'm talking about this circuit.
by ilya
Mon Sep 03, 2018 2:49 pm
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Re: Negative impedance converter reactance

I'm not ready for production quantities...

This resistor sets the frequency in the bridged-t equalizer.
by ilya
Mon Sep 03, 2018 12:35 pm
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Re: Negative impedance converter reactance

Well, the whole point of this exercise is to get rid of an awkward dual rev log 100k pot and replace it with somewhat more friendly dual 10k linear one.
by ilya
Mon Sep 03, 2018 10:41 am
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Re: Negative impedance converter reactance

NR1 and NR2 nodes are where the circuit from the first post (NIC) connects. There are two identical NICs, one with NR1 terminals, another with NR2 terminals.So they connect in parallel to R33 and R34 and are there to mimick the -11K resistance.
by ilya
Mon Sep 03, 2018 1:55 am
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Re: Negative impedance converter reactance

Sorry, got distracted by kids and forgot to upload the other part. The first snippet goes in parallel with each potentiometer.
by ilya
Sun Sep 02, 2018 4:02 pm
Forum: Pro Audio Design
Topic: Negative impedance converter reactance
Replies: 10
Views: 4899

Negative impedance converter reactance

I'm trying to achieve a specific resistance curve and to do that I need to connect a negative resistor in parallel to the variable resistor in the circuit. I'm testing the standard NIC circuit (see attachement) which works mostly as expected. But at some settings of the variable resistor it looks li...
by ilya
Sun Jun 24, 2018 4:40 pm
Forum: Pro Audio Design
Topic: THAT 202XL recreation
Replies: 26
Views: 17971

Re: THAT 202XL recreation

Hmmmm.... That's interesting. So what are the possible ways of trimming the feedthrough then? Applying step impulses and monitoring the output? EDIT: just saw your last post with the quote from Gary. That's what I heard somewhere as well. So this leaves the first question that I asked: I get the low...