[Kenwood] TS-940S Cooling Fan Problem

[Bill Stewart]

Walt, its a 12vdc motor...Bill
----- Original Message ----- 
From: "Walt Breining" <n9wb at nltc.net>
To: "Bill Stewart" <bstewart at ipass.net>
Sent: Friday, October 28, 2005 10:53 AM
Subject: Re: [Kenwood] TS-940S Cooling Fan Problem


> How many volts is the fan made for? I am wondering if it is driven by a
> transistor that is badN9WB
> ----- Original Message ----- 
> From: "Bill Stewart" <bstewart at ipass.net>
> To: "Walt Breining" <n9wb at nltc.net>
> Cc: "kenwood at mailman.qth.net" <>
> Sent: Friday, October 28, 2005 9:29 AM
> Subject: Re: [Kenwood] TS-940S Cooling Fan Problem
>
>
>> Thanks Walt for the reply...
>> I would say for the fan to reliability start every time, it needs at 
>> least
>> 1.5vdc, maybe a tad more. Sometimes it will try to start at a slightly
> lower
>> voltage. Once the voltage gets beyond 1.5 or so, it runs & starts fine. 
>> It
>> draws around 80ma or so when its trying to start. That's probably why the
>> voltage drops from a no-load value of around 18vdc.
>>
>> Thanks to all for the other comments. I think the the prudent thing to do
> is
>> can this fan. I got to thinking about replacing it with a small 120vac
>> muffin fan mounted to the existing fan cage. On my power trans. there
> seems
>> to be two 120v primary windings. I was thinking about hooking the muffin
> fan
>> to the 120v side and let it run all the time (with the unit turned on).
> I'm
>> not sure how much current the fan would pull or how much headroom there 
>> is
>> on the fuse. A dropping resistor could be used to slow it down if needed.
> At
>> least I could hear it running...and as Tim the Tool Man says....MORE
>> POWER...uuuGGGGHHHHH......de Bill Stewart K4JYS
>> ----- Original Message ----- 
>> From: "Walt Breining" <n9wb at nltc.net>
>> To: "Bill Stewart" <bstewart at ipass.net>; <kenwood at mailman.qth.net>
>> Sent: Thursday, October 27, 2005 8:12 PM
>> Subject: Re: [Kenwood] TS-940S Cooling Fan Problem
>>
>>
>> > Bill:
>> > You said that you tried it on another DC supply? Did it run ok or did 
>> > it
>> > still start slow?
>> > If it still started slow, it probably is the fan.
>> > If it starts ok on a good DC supply, there could be a problem with the
>> > circuitry that powers the fan.
>> >
>> > Vy 73, Walt N9WB
>> > Good audio is an Amateur Radio tradition, not a crime.
>> >
>> > ----- Original Message ----- 
>> > From: "Bill Stewart" <bstewart at ipass.net>
>> > To: "kenwood at mailman.qth.net" <Kenwood at mailman.qth.net>
>> > Sent: Thursday, October 27, 2005 8:25 AM
>> > Subject: [Kenwood] TS-940S Cooling Fan Problem
>> >
>> >
>> >> I have a TS-940S, s/n 6040XXX, which has a sluggish cooling fan (on
> left,
>> > facing front, behind the power trans.). Sometimes it will not start. I
>> > have
>> > shot WD-40 in it and tried to get oil to go down the shaft but 
>> > sometimes
>> > it
>> > still won't start and if it does start, it turns slowly & erratically. 
>> > I
>> > measured the voltage to be around 18VDC with the fan disconnected and
>> > connected, a fluctuating .5 to 1.5VDC with the erratic rotation.
>> >> Questions: 1. Is this no-load to load voltage drop normal?
>> >>                  2. Does the voltage and fan speed increase with temp.
>> > rise?
>> >>                  3. If the above is a problem, are there any mods. to
>> > replace this fan or maybe make the fan run all the time?
>> >> The fan runs ok if it gets beyond the low start-up point (on a 
>> >> seperate
>> >> DC
>> > supply).
>> >> Any comments will be appreciated, thanks...Bill K4JYS
>> >> ______________________________________________________________
>> >>
>> >
>> >
>>
>>
>>
>