10k sorts car - forgot the Italian bit in the middle, Re: Top Gear challenge of a few series ago...........
I used colgate orig in my application.
'That' kind of 'lapping' - ill save my money, g/f does that for me buckshee and in her uniform (she's not a nurse/firefighter....hint - handcuffs)
My first trade is that of Offset Printer - RSA(not a bull **** NVQ) degree in 'Fine Arts and Printing'
Eng is second trade and what I do now, as the money went out of printing!
I read in a thread about you winding your own chokes - could you give me a pointer to it, I got a few questions regarding.
I used colgate orig in my application.
'That' kind of 'lapping' - ill save my money, g/f does that for me buckshee and in her uniform (she's not a nurse/firefighter....hint - handcuffs)
My first trade is that of Offset Printer - RSA(not a bull **** NVQ) degree in 'Fine Arts and Printing'
Eng is second trade and what I do now, as the money went out of printing!
I read in a thread about you winding your own chokes - could you give me a pointer to it, I got a few questions regarding.
Yeah thing is they never made it there
now if the cars where maintained in Italy it would have been much different story.
I got to change a couple of nedle roller bearings as we speak work work work
Cokes when I came back
now if the cars where maintained in Italy it would have been much different story.
I got to change a couple of nedle roller bearings as we speak work work work
Cokes when I came back
Okey dokey Cokes
Found UK shoop that sels Cooper wire by the kilo
I bought 2 kilos of 2.21mm diameter (top of my head)
and wound them up
Cokes trick is to keep resistance low and make up 2.2 H coils
Not shure if Jacco or mighty Zen posted proper details before.
To make long story short I recon I shuld have bought 4 Kilos of it
Any way still 1 H keeping MR riple at bay is better than none
this with CRCLC for a total off 150mF
You got more current with turbo so less resistance on CRC so more Ripple
Cokes came handy
Toughts next time I am after self punishment I am going to wind the 2 cores side by side and make common Coke.
I will try to post details about shop tmorow as it is all in the home puter
Found UK shoop that sels Cooper wire by the kilo
I bought 2 kilos of 2.21mm diameter (top of my head)
and wound them up
Cokes trick is to keep resistance low and make up 2.2 H coils
Not shure if Jacco or mighty Zen posted proper details before.
To make long story short I recon I shuld have bought 4 Kilos of it
Any way still 1 H keeping MR riple at bay is better than none
this with CRCLC for a total off 150mF
You got more current with turbo so less resistance on CRC so more Ripple
Cokes came handy
Toughts next time I am after self punishment I am going to wind the 2 cores side by side and make common Coke.
I will try to post details about shop tmorow as it is all in the home puter
Bk,
I have the shop bookmarked - reading your post on the subject of winding 2 cores side by side caught my eye. Two years ago I worked for a forklift maintenance company and learnt a bit about re-winding elec motors, this was out-sourced to a local company, I was thinking of swinging by the place and seeing if I could get a price on a larger weight for a single wind option.
thanks in advance.
I have the shop bookmarked - reading your post on the subject of winding 2 cores side by side caught my eye. Two years ago I worked for a forklift maintenance company and learnt a bit about re-winding elec motors, this was out-sourced to a local company, I was thinking of swinging by the place and seeing if I could get a price on a larger weight for a single wind option.
thanks in advance.
Don't fret Bk, I found the posts I was after - it dawned on me that it would be some where in one of the 'F5' related threads.
For everibody else this is link to shoop
wires.co.uk : Enamelled Copper Wire
Pain in the but to wind by hand but if you don't know where it can be done at home
😀Have you kept any spare battery of the fork lift
would run turbo nicely for a few hours😀
Time to get same spatcha been up 25 hours night night
wires.co.uk : Enamelled Copper Wire
Pain in the but to wind by hand but if you don't know where it can be done at home
😀Have you kept any spare battery of the fork lift
would run turbo nicely for a few hours😀
Time to get same spatcha been up 25 hours night night
Wellllll .......my first amp was a chip amp, built about 3 months after a magazine revued the Final Audio 1........ after listening to it for a month, I ripped out the trafo and recitifiers and powered it with batteries. All was 'sweeter'
Then I removed the psu caps, the improvement was 'astounding'. Took me a while to find an amp to replace it.
So..... forklift batteries and big class A... Oh my!
tis a thought eh?
Then I removed the psu caps, the improvement was 'astounding'. Took me a while to find an amp to replace it.
So..... forklift batteries and big class A... Oh my!
tis a thought eh?
I'm thinking about getting some Constantan wire and placing it across the sink with thermal grease and measure how much the temperature increases for a given dissipation. Do you guys think it would work? This way I can be sure how far I can go with it.
Even so, a Class AB amp inside this case would be limited to 170W/channel, so that worst case dissipation is 85W/channel, right? Or more than 25C temperature rise is allowed when the amp is retaining half of the output power?
Obrigado
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One of the attributes of Constantan
Worst case would be @ ~60% of maximum power output continuously while the mains power is at maximum voltage.
That will probably give a worst case heat dissipation of 120W/channel.
If you want to design for that worst case scenario, then expect the heatsinks to be enormous.
is that it's thermal coefficient of resistance does not change, significantly.
No.
Worst case would be @ ~60% of maximum power output continuously while the mains power is at maximum voltage.
That will probably give a worst case heat dissipation of 120W/channel.
If you want to design for that worst case scenario, then expect the heatsinks to be enormous.
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Easier would be to just stick a power resistor/transistor to the heatsink with a spring.
Worst case for a Class A amplifier is the idle situation. With a signal on the input, the load takes care of part of the dissipation.
Thermal calculation starts with the steady-state operating temperature of the heatsink.
Heatsink calculation for a Class AB amp starts with worst case dissipation when driving a load.
Temperature will vary and max temperature of the heatsink for the math is much higher.
For the thermal calculation, the load number has to be picked.
Why some commercial manufacturers had a regular version of an amp model, and a Heavy Duty type of the same one, with a bumped-up power supply and increased heat sinking capacity (aka heatsink exchange).
As Class AB is a compromise by definition (imo), monitoring dissipation and temperature is standard practice (V/I limiters, output relays, thermal breakers).
Which is called smart engineering, only a commercial fool would lay out a subwoofer power amp and market it as a domestic amplifier.
So the typical high volume Japanese power amp has whimpy heatsinks and shouldn't drive low impedance loads.
A serial production PA amplifier on the other hand will have a fan on stand-by, for when the going gets rough.
Story is different when the amp is manufactured in/for elevated temperature areas.
Your Nashville amp was made do Brasil, so it has larger than average heatsinks, and very pretty ones imo.
De Naah-da.
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Spring? I didn't understand!
Why 2 heatsinks in series work better than one?
i've been thinking now. and it will be a V3 over here😀
with 0.7A bias pr device. i start there. maybe i can pump up the bias a little bit. rails will be +/-32V.
edit: sorry. 0.8A
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a single pair will give a maximum ClassA output power of P(ClA) = [2*0.8]^2 * 8ohms / 2 = 10W into 8r0.
If you fit a 2pr output stage the maximum ClassA output Power increases to 4times (P*2^2) the single pair. i.e. 40W
a 3pair stage will give 90W (*3^2)
This latter 3pr will require an output voltage of 0.8* 2 *3pr * 8ohms = 38.4Vpk
This will require operating supply rails of ~ +-42Vdc
Substitute 1pr or 2pr or 4pr into that formula to find Vpk for the alternative output arrangements.
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