pras - re-label that "9V" with 24V
9V is "just" battery voltage you're using for actual gate voltage generation , while drain voltage of 24V (you're using) is significant value
so , that's all one need to know from numbers :
"this SIT is conducting 2A from 24V rail , when gate is at -2.74V control voltage "
again , 9V figure is irrelevant for data
edit: I hope that picture is just for showing alligator clips arrangement
....... I see that SIT is not sitting on heatsink surface ; of course that you know that for test SIT must be firmly in contact with heatsink - either clamped or bolted
9V is "just" battery voltage you're using for actual gate voltage generation , while drain voltage of 24V (you're using) is significant value
so , that's all one need to know from numbers :
"this SIT is conducting 2A from 24V rail , when gate is at -2.74V control voltage "
again , 9V figure is irrelevant for data
edit: I hope that picture is just for showing alligator clips arrangement
....... I see that SIT is not sitting on heatsink surface ; of course that you know that for test SIT must be firmly in contact with heatsink - either clamped or bolted
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pras - re-label that "9V" with 24V
9V is "just" battery voltage you're using for actual gate voltage generation , while drain voltage of 24V (you're using) is significant value
so , that's all one need to know from numbers :
"this SIT is conducting 2A from 24V rail , when gate is at -2.74V control voltage "
again , 9V figure is irrelevant for data
edit: I hope that picture is just for showing alligator clips arrangement
YES 9V is "just" battery voltage using for actual gate voltage generation , while drain voltage of 24V (you're using) is significant value
24V 2A
Thank you for reminding me that I may have been on vacation for a few days and my head is stupid.
Thank you for reminding me that I may have been on vacation for a few days and my head is stupid.
Bravo pras~!
I was even more impressed by ZM's interpretation...
Yes, thank you very much. Help me.
OK pras I believe you are from your Moon Festival holidays. We have similar one in Korea.
You have nothing to lose by asking questions here especially to ZM.
Do as he says. Do not assume things, just ask questions and confirm.
And then supply the matched pairs at reasonable price, that includes your time and effort. But you are also kind of educated here, so sell at good price. You are dealing with hobbyists here and we are nasty consumers....
Cheers
OK pras I believe you are from your Moon Festival holidays. We have similar one in Korea.
You have nothing to lose by asking questions here especially to ZM.
Do not assume things, just ask questions and confirm.
And then supply the matched pairs at reasonable price, that includes your time and effort. But you are also kind of educated here, so sell at good price. You are dealing with hobbyists here and we are nasty consumers....
Cheers
Hello, yes, I did have a few days off, and in the case of 24V power, I was written as 9V.
Are you Korean?
I'm glad to meet you. I have two friends in Korea. They come to China with their children and family while working. They come to China five times a year. We eat together, talk about business, talk about life, talk about family.
After a few days' vacation, it's stupid to come back to work. 9V is battery.
Actually it's 24V. I wrote the 9V battery. Actually it should be 24V. My test is like this. In this way:
9V is "just" battery voltage you're using for actual gate voltage generation, while drain voltage of 24V is significant value
So, that's all one need to know from numbers:
"This SIT is conducting 2A from 24V rail, when gate is is"
Again, 9V figure is irrelevant for data
Actually it's 24V. I wrote the 9V battery. Actually it should be 24V. My test is like this. In this way:
9V is "just" battery voltage you're using for actual gate voltage generation, while drain voltage of 24V is significant value
So, that's all one need to know from numbers:
"This SIT is conducting 2A from 24V rail, when gate is is"
Again, 9V figure is irrelevant for data
@ ChromenutsDave from Cinemag reached out to me...they’re very busy.
The order is placed and paid for...well, after a slight mishap with the shipping costs being accidentally billed at $999.00...LOL!!! It’s all sorted out now and they should be here sooner or later.
I’m not in a huge rush as I’m still wrestling with my tonearm project and a few other things.
To be honest, I have a slew of things I feel obligated to finish before diving into the Sissy...including my F2J, trying some iron on my DCB1 and setting up my other horns with the Lowthers.
Did I mention I’m trying to renovate an old sunroom on the back of the house to turn it into a actual listening room? Oh, and the cars needed work done on them and the furnace had to be serviced.
Thanks hope we get more hi nickels from Cinemags to try..
Wise decision!
Finish all older builds before start new ones bring You satisfaction
and dedicated listening place with his own specialized power line * for audio use only *
with acoustic room traitements is a many aficionados dream.
Haha after that Vfet and SIT's amplifiers look like future cheery on the cake
I have not seen one photo ( there are plenty of photos coming from you) with THS51 bolted on the Heatsink and testing like Zen Mod had shown earlier. I am not suspecting but are you getting that the testing is required under proper thermal condition?
You flip the record above, the temperature you are talking about is the temperature in the room, right?
A diy friend from the previous one asked me to buy a temperature sensor, then I went to buy it. The indoor temperature sensor is 28°. Put this temperature sensor on the aluminum heat sink and start working on the THF-51S. The temperature display is At 48°-65°, I didn't let the THF-51S stay on the heat sink for a long time, because I still have a lot of work to do, there is no way to stay on top of a THF-51S, I see the temperature rises. High, I will change another THF-51S.
Then re-adjust to 9V and then 2A, the temperature sensor is turned back on and continues to work.
I don't know if this is right?
If my temperature sensor is wrong on the heat sink, should the thermometer be placed on the THF-51S or on the heat sink?
I'm actually a very stupid person
But there are a lot of smart DIY friends in this BBS, they told me to buy something, buy some tools, I'll buy them, I'll do them, and I went to my friend's studio and asked him to help me solder the tin. It seems that many people still don't understand my method.
Just the other day, some diy friends said they needed a temperature sensor, and I went to buy one
Many people praised correctly, but some said it was wrong. I even measured a lot and took pictures and sent them to them. They replied that I could not understand
In the end, everyone has different demands, everyone strives for perfection, everyone strives for something better, so everyone's requirements are especially strict, I still think I have paid
But there are a lot of smart DIY friends in this BBS, they told me to buy something, buy some tools, I'll buy them, I'll do them, and I went to my friend's studio and asked him to help me solder the tin. It seems that many people still don't understand my method.
Just the other day, some diy friends said they needed a temperature sensor, and I went to buy one
Many people praised correctly, but some said it was wrong. I even measured a lot and took pictures and sent them to them. They replied that I could not understand
In the end, everyone has different demands, everyone strives for perfection, everyone strives for something better, so everyone's requirements are especially strict, I still think I have paid
oh well , beauty of chinese-english-chinese-english automatic translation .....
SIT must be fixed to heatsink while doing the measurement , with fan blowing on heatsink to keep it cool
fixed means either clamped or bolted SIT to heatsink , but in any case thermal contact between SIT and heatsink must be firm and good
if that is not the case - why even bothering to keep heatsink on the bench
look at this picture , as many times is needed to get things right:
If you didn't had proper thermal contact between SIT and heatsink , while doing your measurements ....... numbers are just of informal character .....
sort that issue of SIT-heatsink , tear down all labels and measure them all again
SIT must be fixed to heatsink while doing the measurement , with fan blowing on heatsink to keep it cool
fixed means either clamped or bolted SIT to heatsink , but in any case thermal contact between SIT and heatsink must be firm and good
if that is not the case - why even bothering to keep heatsink on the bench
look at this picture , as many times is needed to get things right:
If you didn't had proper thermal contact between SIT and heatsink , while doing your measurements ....... numbers are just of informal character .....
sort that issue of SIT-heatsink , tear down all labels and measure them all again
Pras, if you measure the temperature on the sink it will be lower than on the sit capsule.
Let’s say that 60c on the sink will be maybe 70c on the capsule of the sit and maybe 80-90c or even more at the junction.
I saw some time ago someone(Nelson if I remember corectly) that adviced to use a thermostat attached to the sink. This will command a resistor to heat up the sink and thus keeping the sink at a constant temperature of let’s say 45-50c. Then what you have to do is to attach the sit, wait a while(1minute or maybe less) that the sit gets in temperature and after take the measurement.
As Zen said for this application we don’t need very precise matching but for other aps we will need accurate matching and I bet that there are people ready to pay the price for this kind of matching. Now it depends on you how much time do you have to match these devices and the money you want to earn but usually less hassle less money earned. A good rig for matching devices is always good to have near you
Let’s say that 60c on the sink will be maybe 70c on the capsule of the sit and maybe 80-90c or even more at the junction.
I saw some time ago someone(Nelson if I remember corectly) that adviced to use a thermostat attached to the sink. This will command a resistor to heat up the sink and thus keeping the sink at a constant temperature of let’s say 45-50c. Then what you have to do is to attach the sit, wait a while(1minute or maybe less) that the sit gets in temperature and after take the measurement.
As Zen said for this application we don’t need very precise matching but for other aps we will need accurate matching and I bet that there are people ready to pay the price for this kind of matching. Now it depends on you how much time do you have to match these devices and the money you want to earn but usually less hassle less money earned. A good rig for matching devices is always good to have near you
Pras, if you measure the temperature on the sink it will be lower than on the sit capsule.
Let’s say that 60c on the sink will be maybe 70c on the capsule of the sit and maybe 80-90c or even more at the junction.
I saw some time ago someone(Nelson if I remember corectly) that adviced to use a thermostat attached to the sink. This will command a resistor to heat up the sink and thus keeping the sink at a constant temperature of let’s say 45-50c. Then what you have to do is to attach the sit, wait a while(1minute or maybe less) that the sit gets in temperature and after take the measurement.
As Zen said for this application we don’t need very precise matching but for other aps we will need accurate matching and I bet that there are people ready to pay the price for this kind of matching. Now it depends on you how much time do you have to match these devices and the money you want to earn but usually less hassle less money earned. A good rig for matching devices is always good to have near you
Yes, the fan is always blowing the wind to the radiator and the THF-51S.
But the screws are tight, and some friends will say, how this is so ugly, old, used (the appearance of such a person does not like it)
The temperature sensor needs to be placed on the radiator or on the body of the THF-51S. At what temperature, at what temperature, I need to know what is right and when can I end it.