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  1. Ic7000
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Overheating - urban legend

 

Le 01/01/2025 à 14:43, Bob KM4RL a écrit?:
A 2 watt resistor is good for 12 volt systems. I favor 150 Ohm resistors
to bypass fan thermostats in Astron SS-30 power supplies and other equipment.
The top cover of the IC7000 is a heat sink. There's a reason it has thermal pads.
Take a thermal camera and you'll see that the heating isn't that great after all.

The modification with the fan running all the time will cause dust to accumulate
inside over the long term. You'll need to clean it from time to time.

Personally, I cool it with an external fan and a KSD9700
because the hot air is blocked by a shelf 10 cm above it.

Before, it wasn't cooled down and the unit has been in operation
for almost 100,000 hours...

Search my videos on tiktok and thermal camera measurement...
??? ?

Best regards,
Ludovic - F5PBG
 

Ludovic

Data , what a great idea!

73
Kurt
KD6LZV

On Jan 1, 2025, at 10:30 AM, Ludovic Ludo via groups.io <f5pbg@...> wrote:

?Le 01/01/2025 à 14:43, Bob KM4RL a écrit :
A 2 watt resistor is good for 12 volt systems. I favor 150 Ohm resistors
to bypass fan thermostats in Astron SS-30 power supplies and other equipment.
The top cover of the IC7000 is a heat sink. There's a reason it has thermal pads.
Take a thermal camera and you'll see that the heating isn't that great after all.

The modification with the fan running all the time will cause dust to accumulate
inside over the long term. You'll need to clean it from time to time.

Personally, I cool it with an external fan and a KSD9700
because the hot air is blocked by a shelf 10 cm above it.

Before, it wasn't cooled down and the unit has been in operation
for almost 100,000 hours...

Search my videos on tiktok and thermal camera measurement...
?

Best regards,
Ludovic - F5PBG
 

Data...
?
from new the IC7000 ran 14-18C hotter than ambient (20C).? The hot spots
aligned with thermal pads.
?
Testing with a ditter on CW at half power netted a 30C climb in the hottest
areas.? The heatsink for the finals was at 54C, operation? at that level or
higher will impact the life of the finals and drivers (close thermal location).
?
Opening the unit while hot showed NO FAN operation.? Heating the
thermister used to sense temps was no fan operation until it was over
45C at the sensor.? ??
?
That is too hot for good lifespan.? That's based on my experience and
knowledge of reliability engineering.? ?Sure one unit may last for ever
but do that to 1000s of them and that will not be true.
?
First fix tried was new thermister, then altered the circuit values for lower?
activation temp (~32C).? That helped when under stress (during high use
TX) but the unit was always very warm.? Relocating the thermister to the
finals (heatsink) helped keep them somewhat cooler.? Adding the fan mod
(resistor) caused a significant drop in?the case temp of +14-18C (over ambient)
measured earlier to +2- to +3C over ambient.? ? It also lowered the temps
of the finals and drivers?during intermittent operation.? ?Being cooler also
lowered the timebase (frequency) error and that showed most on
144 and 432 operations.
?
Over all the high temps and thermal cycles is known to increase failure
rates over time.? Having the radio running generally cooler cannot hurt.
If dust is an issue then a occasional cleaning is worth doing.
?
--
Allison
 

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Allison

Thanks for the data.
I have been lucky with my unit, ?now going on ?15 years of admittedly, light duty.

Seems like there may be ? ficant unit to unit variability. Maybe different brands of heat paste ? or other differences in heat conduction chain.

73

Kurt

On Jan 7, 2025, at 9:04 AM, ajparent1/kb1gmx via groups.io <kb1gmx@...> wrote:

?
Data...
?
from new the IC7000 ran 14-18C hotter than ambient (20C).? The hot spots
aligned with thermal pads.
?
Testing with a ditter on CW at half power netted a 30C climb in the hottest
areas.? The heatsink for the finals was at 54C, operation? at that level or
higher will impact the life of the finals and drivers (close thermal location).
?
Opening the unit while hot showed NO FAN operation.? Heating the
thermister used to sense temps was no fan operation until it was over
45C at the sensor.? ??
?
That is too hot for good lifespan.? That's based on my experience and
knowledge of reliability engineering.? ?Sure one unit may last for ever
but do that to 1000s of them and that will not be true.
?
First fix tried was new thermister, then altered the circuit values for lower?
activation temp (~32C).? That helped when under stress (during high use
TX) but the unit was always very warm.? Relocating the thermister to the
finals (heatsink) helped keep them somewhat cooler.? Adding the fan mod
(resistor) caused a significant drop in?the case temp of +14-18C (over ambient)
measured earlier to +2- to +3C over ambient.? ? It also lowered the temps
of the finals and drivers?during intermittent operation.? ?Being cooler also
lowered the timebase (frequency) error and that showed most on
144 and 432 operations.
?
Over all the high temps and thermal cycles is known to increase failure
rates over time.? Having the radio running generally cooler cannot hurt.
If dust is an issue then a occasional cleaning is worth doing.
?
--
Allison
 

Where was the thermistor located before you moved it?
Bob W4JFA

On Tue, Jan 7, 2025 at 12:04?PM ajparent1/kb1gmx via <kb1gmx=[email protected]> wrote:
Data...
?
from new the IC7000 ran 14-18C hotter than ambient (20C).? The hot spots
aligned with thermal pads.
?
Testing with a ditter on CW at half power netted a 30C climb in the hottest
areas.? The heatsink for the finals was at 54C, operation? at that level or
higher will impact the life of the finals and drivers (close thermal location).
?
Opening the unit while hot showed NO FAN operation.? Heating the
thermister used to sense temps was no fan operation until it was over
45C at the sensor.? ??
?
That is too hot for good lifespan.? That's based on my experience and
knowledge of reliability engineering.? ?Sure one unit may last for ever
but do that to 1000s of them and that will not be true.
?
First fix tried was new thermister, then altered the circuit values for lower?
activation temp (~32C).? That helped when under stress (during high use
TX) but the unit was always very warm.? Relocating the thermister to the
finals (heatsink) helped keep them somewhat cooler.? Adding the fan mod
(resistor) caused a significant drop in?the case temp of +14-18C (over ambient)
measured earlier to +2- to +3C over ambient.? ? It also lowered the temps
of the finals and drivers?during intermittent operation.? ?Being cooler also
lowered the timebase (frequency) error and that showed most on
144 and 432 operations.
?
Over all the high temps and thermal cycles is known to increase failure
rates over time.? Having the radio running generally cooler cannot hurt.
If dust is an issue then a occasional cleaning is worth doing.
?
--
Allison
 

Excellent work, Allison. ?Thank you for sharing.

I’m much happier with things since doing one of the published fan control mods (so that fan is enabled at a lower temperature). ? ?
?
Personally, I didn’t feel the need to alter the position of the thermistor, or thermally bond it to the heat sink (as described in the fan control modification). ?Time will tell :-)
?
 

Initial position of thermistor was? roughly center of the edge of the board.
I moved it (extended leads) to the area to one side of the finals where it
seemed to get the hottest.
?
I've seen more than a few that run very warm.?
?
--
Allison
 

Allison and all, I've been wondering if the thermistor can be moved to make contact with either the heat sink or one of the final transistors
thinking it would get hotter sooner and turn the fan on sooner?
I only worked on a friend's radio a few months ago and I can't remember the locations. I do have a downloaded service manual
but I cannot find where it shows the thermistor location, if it does. I did find D2401, DAN202K that may be the thermistor
but what I have I cannot confirm.

I appreciate your help Allison. I would like to get my friends radio to run cooler before summer when he uses it portable to
do POTA.

Any other hints would sure be?appreciated.

Bob W4JFA


On Wed, Jan 8, 2025 at 10:46?AM ajparent1/kb1gmx via <kb1gmx=[email protected]> wrote:
Initial position of thermistor was? roughly center of the edge of the board.
I moved it (extended leads) to the area to one side of the finals where it
seemed to get the hottest.
?
I've seen more than a few that run very warm.?
?
--
Allison
 

Bob, you must not have read what came before.
?
See:
?
It takes a bit of soldering skill and some fine wire.
?
--
Allison
 

Sorry I missed it. Thank you


On Wed, Jan 8, 2025 at 3:09?PM ajparent1/kb1gmx via <kb1gmx=[email protected]> wrote:
Bob, you must not have read what came before.
?
See:
?
It takes a bit of soldering skill and some fine wire.
?
--
Allison
 

Thanks for the data.
My thermal camera contradicts what it says...
?
We'll talk about it in 10 years' time.
My IC7000 will probably still be alive.
Me, on the other hand...

The radiators I saw on the sides of the IC7000 will be
in my youtube video on the subject, as it's a very
amusing way of cooling the IC7000 very efficiently.

I'm a tease, I know...
73's de Ludovic - F5PBG

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