KL 203 100 Watt Amp Fan Mod
- George EI7KO
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Re: KL 203 100 Watt Amp Fan Mod
Yes it is.
BLUE LED'S ARE BEST!!!!
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- George EI7KO
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Re: KL 203 100 Watt Amp Fan Mod
Admiral wrote:Yeah, you and Ashtec should get together.
I wish I could work out how to get some LEDs in my old 757. The old bulbs are as dim as a dim thing.
It's not that hard to do. You better bulk buy some extra bright blue ones, they are the best like...
BLUE LED'S ARE BEST!!!!
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- Admiral
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Re: KL 203 100 Watt Amp Fan Mod
Someone once told me that the original bulbs were also fuses, so I chose to leave well alone.Irishham1127 wrote:Admiral wrote:Yeah, you and Ashtec should get together.
I wish I could work out how to get some LEDs in my old 757. The old bulbs are as dim as a dim thing.
It's not that hard to do. You better bulk buy some extra bright blue ones, they are the best like...
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- George EI7KO
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Re: KL 203 100 Watt Amp Fan Mod
Dunno mate. not familiar with the breed at all. used as fuses for what exactly??
BLUE LED'S ARE BEST!!!!
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Re: KL 203 100 Watt Amp Fan Mod
Well, what a way to encourage someone to try improving their kit and posting it on here.
I suspect that threads like this will put people off from both.
I suspect that threads like this will put people off from both.
- George EI7KO
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Re: KL 203 100 Watt Amp Fan Mod
I doubt it. Didn't stop me.
BLUE LED'S ARE BEST!!!!
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- Mudslinger
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Re: KL 203 100 Watt Amp Fan Mod
IMO if it is your radio you should be able to do what you like to it.
However don't expect everyone to like it as everyone likes different things.
Also if you come on asking what people think then expect both positive and negative comments.
However don't expect everyone to like it as everyone likes different things.
Also if you come on asking what people think then expect both positive and negative comments.
Mudslinger - Simon
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There is no such thing as a Fidelity 1000 which is too good to scrap.
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Re: KL 203 100 Watt Amp Fan Mod
modern cb amps benefit greatly from adding a fan especially the AB bias ones, even the class C amps have farty little heatsinks that get way too hot,
AB bias amps have no thermal tracking & use a bias switching circuit that has its own positive temperature drift compounding the issue pushing the transistors towards thermal runaway as the amp gets hot when it should throttle back the bias to keep idle current in check like ALL decent amps use,
fans and bias tracking mods are far more use than anything cosmetic, rm/zetagi benefit from all the extra cooling you can give them.
AB bias amps have no thermal tracking & use a bias switching circuit that has its own positive temperature drift compounding the issue pushing the transistors towards thermal runaway as the amp gets hot when it should throttle back the bias to keep idle current in check like ALL decent amps use,
fans and bias tracking mods are far more use than anything cosmetic, rm/zetagi benefit from all the extra cooling you can give them.
W8JI
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"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
- cjay
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Re: KL 203 100 Watt Amp Fan Mod
If you aim it right you cold even have a laminar flow water distribution system and 'pipe' the light between barrels.Irishham1127 wrote:mmmm....water barrels with blue leds in them...mmmm
- sureshot
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Re: KL 203 100 Watt Amp Fan Mod
Looking back over previous pages, when it comes to semiconductors heat is an enemy, well over rated thermal limit, even so cooler will prolong life of the amp radio etc, valves tubes might need or even benefit from heat, but the emphasis should be on cool as in modern electronics. Ok some heat is inevitable but kept under control extends useful life.
CB call. Shipwreck.
- cjay
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Re: KL 203 100 Watt Amp Fan Mod
Most semiconductors are good to work at temperatures that will cook eggs (Vishay quote 175C operating temp for the IRF520), it's crap design that causes problems with heat. Managing heat doesn't 'increase life' it just allows the device to work for its expected life.sureshot wrote:Looking back over previous pages, when it comes to semiconductors heat is an enemy, well over rated thermal limit, even so cooler will prolong life of the amp radio etc, valves tubes might need or even benefit from heat, but the emphasis should be on cool as in modern electronics. Ok some heat is inevitable but kept under control extends useful life.
MOSFETS, as used in the KL203, increase their on resistance, which basically means the hotter the device gets the less it conducts so it won't go into thermal runaway, as long as the drive remains constant then it will run day in day out at temperatures that will be painful to the touch.
Bipolar transistors are a bugger for thermal runaway which can kill a device in seconds (or less) if it enters that state.
- bluegrass69
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Re: KL 203 100 Watt Amp Fan Mod
This is how I run my KL203P linear. The plastic box came from Maplins with a hole cut at both sides and a computer fan in the lid. The warm air blows out of a slot at both sides and even on long FM 'overs' I can barely feel the heat. The 12volt fan was a bit noisy when running at 13.8volts so I slowed it down with a dropping resistor.
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- Mudslinger
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Re: KL 203 100 Watt Amp Fan Mod
I had better not post up a picture of how I run mine.
The fan is just resting on top, and is stopped from vibrating off by electrical tape.
The fan is just resting on top, and is stopped from vibrating off by electrical tape.
Mudslinger - Simon
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There is no such thing as a Fidelity 1000 which is too good to scrap.
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There is no such thing as a Fidelity 1000 which is too good to scrap.
- cb4ever104
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Re: KL 203 100 Watt Amp Fan Mod
Better not Simon , or you might be next
Some things are better left hidden
Some things are better left hidden
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Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.
Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.
- cb4ever104
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Re: KL 203 100 Watt Amp Fan Mod
That looks real nice !bluegrass69 wrote:This is how I run my KL203P linear. The plastic box came from Maplins with a hole cut at both sides and a computer fan in the lid. The warm air blows out of a slot at both sides and even on long FM 'overs' I can barely feel the heat. The 12volt fan was a bit noisy when running at 13.8volts so I slowed it down with a dropping resistor.
30TM060
Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.
Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.