I was having a long QSO with a friend on 12 meters and out of nowhere he tells me i stated to sounds real bad.
my SWR was good the whole time but i felt the back of the radio and it was HOT!!! i was not able to hole my hand to the back of it..
I opened it up and put a PC fan over it to cool it down.. by then my friend took off so i just let the fan cool the radio down.. i later that night fired it up and found some people talking 40m in north Dakota and Georgia the reports they gave me i was sounding good. so my conclusion was the radio got to hot and the finals went nuts.
when i key down the fans do spin. i seen a mod for the fans to come on sooner and i was wondering if any one has done this mod?
i was going to temporarily replace the Thermal censer with a pot and see at why point the fans kick on and take a reading off the pot at least i can make sure the fan controller is working.. then plug the thermal probe into my multi meter and see at what point it Resistance matches and at what temp..
http://www.mods.dk/view.php?Article...da62d1c9&i=1-kenwood-TS-450-TS450-690-fan-mod
Locate the FAN board and remove the R6 (3.3K), replace it with 4.7K resistor, not necessarily SMD any carbon film 1/4w would do.
Reattach all the connectors for the PA board and on top the Filter board, solder the RF connector and ground.
my SWR was good the whole time but i felt the back of the radio and it was HOT!!! i was not able to hole my hand to the back of it..
I opened it up and put a PC fan over it to cool it down.. by then my friend took off so i just let the fan cool the radio down.. i later that night fired it up and found some people talking 40m in north Dakota and Georgia the reports they gave me i was sounding good. so my conclusion was the radio got to hot and the finals went nuts.
when i key down the fans do spin. i seen a mod for the fans to come on sooner and i was wondering if any one has done this mod?
i was going to temporarily replace the Thermal censer with a pot and see at why point the fans kick on and take a reading off the pot at least i can make sure the fan controller is working.. then plug the thermal probe into my multi meter and see at what point it Resistance matches and at what temp..
http://www.mods.dk/view.php?Article...da62d1c9&i=1-kenwood-TS-450-TS450-690-fan-mod
- Relocate the temperature sensor (thermistor ) closer to the PA transistors.
- Lower the temperature (around 10-15 degrees C) when the fan kicks in by replacing R6 3.3K with 4.7K from the fan board X59-3370-00
Locate the FAN board and remove the R6 (3.3K), replace it with 4.7K resistor, not necessarily SMD any carbon film 1/4w would do.
Reattach all the connectors for the PA board and on top the Filter board, solder the RF connector and ground.
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