Howard, perhaps I wasn't clear. If I make my own winch for the TX-489, I
will build it just as I built the one for my present tower. It has a 2 HP
bi-directional motor turning a small diameter pulley for a V-belt. The
other end of the belt turns a significantly larger diameter pulley and a 90
degree Hub City jack screw transmission. The output shaft of the
transmission turns a drum for the 5/16 inch stainless aircraft cable(AKA
wire rope). When I turn off the juice while lowering the tower, the motor
of course slows down, and the 90 degree jack screw transmission slows down
with it. Once stopped, which takes circa 1 second, the drum can no longer
turn because of the jack screw. Hence no need for a friction brake. I
haven't looked to see what US Tower gets for their motorized winch, but I
can build a copy of the one I currently have on my present tower for about
$1200, the most expensive piece being the Hub City 90 degree tranny.
Alan
Alan R. Downing
Phoenix, AZ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Howard, W A 9 Y B W
Sent: Monday, September 29, 2014 12:06 PM
To: [log in to unmask]
Subject: Re: US Tower TX-489
Alan,
Unless US Tower is using a different winch than I have, it is not the type
with a jack screw.
Howard
----- Original Message -----
From: "Alan R. Downing" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, September 29, 2014 1:28 PM
Subject: Re: US Tower TX-489
> Howard, The winch on my 75 foot tower doesn't have a friction brake. All
> braking is handled by the jack screw. It is impossible to turn a jack
> screw
> backwards, so as the motor slows down, which it does in less than a
> second,
> the braking takes place. I would use the same arrangement on the TX-489's
> winch.
>
> Alan
>
>
>
> Alan R. Downing
> Phoenix, AZ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Howard, W A 9 Y B W
> Sent: Monday, September 29, 2014 10:06 AM
> To: [log in to unmask]
> Subject: Re: US Tower TX-489
>
> Alan,
>
> If you decide to add your own motor and gearbox to the hand winch, I need
> to
>
> caution you about something. You will need to be careful when lowering
> the
> tower because the friction brake in the winch will seriously overheat if
> you
>
> come all the way down in one operation. You will need to break the
> lowering
>
> up in to several shorter periods of time interlaced with a cool-down time
> for the brake wafers.
>
> Howard #3, W A 9 Y B W
>
> ----- Original Message -----
> From: "Alan R. Downing" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, September 28, 2014 2:45 PM
> Subject: Re: US Tower TX-489
>
>
>> Hello again Howard. You describe precisely what I employ on my present
>> 75
>> foot motorized crankup. I had a sighted friend run the tower up to the
>> point where the first moveable section, namely the second section of the
>> tower, was 12 inches from hitting the upper stop. We then tied a rope
>> from
>> the bottom rung of that second section of tower, to a rung on the bottom
>> section at about waiste high. I simply feel the rope being pulled thru
>> my
>> left hand, and when it is almost tight I stop the winch and run it up the
>> last several inches by turning the pulleys by hand. I am only giving up
>> about 1 foot in over all height by doing it this way, and no excessive
>> stress is applied to the 5/16 inch stainless aircraft cable.. I can do
>> this
>> US tower the exact same way. I have the makings of two limit switches,
>> but
>> the effort needed to make it all work isn't worth it to me. Call me
>> lazy,
>> HiHi.
>>
>> Alan
>>
>>
>>
>>
>>
>> Alan R. Downing
>> Phoenix, AZ
>>
>>
>> -----Original Message-----
>> From: For blind ham radio operators
>> [mailto:[log in to unmask]]
>> On Behalf Of Howard, W A 9 Y B W
>> Sent: Sunday, September 28, 2014 12:21 PM
>> To: [log in to unmask]
>> Subject: Re: US Tower TX-489
>>
>> Alan,
>>
>> One disadvantage of the home made motorized winch is the lack of limit
>> switches, however, I'm sure with a little ingenuity something could be
>> fabricated.
>>
>> In lieu of limit switches, one could attach a piece of rope to the bottom
>> of
>>
>> the top section, crank the tower most of the way up, stopping perhaps
>> three
>> or four feet short,put a knot in the rope at a point, say at the height
>> of
>> the winch and when the knot gets to that point, you would stop the motor
>> having the three or four feet of safety room. On an eighty-nine foot
>> tower
>> the four feet of safety height would only amount to about twelve inches
>> before the second section from the bottom would hit the stop. This stop
>> offers plenty of resistance that can be felt when using a manual winch,
>> however, with a motorized winch without safety switches, it would be hard
>> to
>>
>> detect that you have hit the stop thus now stressing the whole system
>> including possibly breaking the cable or winch. That is why I suggest
>> the
>> three to four feet of safety room which might be better if six to eight
>> feet. Eighty-one feet of antenna height verses the eighty nine wouldn't
>> make any difference and you have plenty of safety room to stop your
>> motor.
>>
>> Just some thoughts.
>>
>> Howard #3, W A 9 Y B W
>>
>> ----- Original Message -----
>> From: "Alan R. Downing" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Sunday, September 28, 2014 9:05 AM
>> Subject: Re: US Tower TX-489
>>
>>
>>> Hello Howard, thanks for your input. I can easily fabricate a motorized
>>> winch by buying a 1 or 2 HP Grainger motor and a 90 degree transmission
>>> from
>>> Hub City in Oowa and some pieces of steel. Stick weld the whole
>>> contraption
>>> together and bingo, a custom built electric winch. I have done that
>>> very
>>> thing before, but I have gotten lazy in my 64 years on this planet, Hi.
>>> I
>>> will check prices with US Tower, and make up my mind. I could certainly
>>> put
>>> up the tower with the manual winch, then fabricate the electric winch
>>> afterwards and make the switch.
>>>
>>> Best 73
>>>
>>> Alan
>>>
>>>
>>> Alan R. Downing
>>> Phoenix, AZ
>>>
>>> -----Original Message-----
>>> From: For blind ham radio operators
>>> [mailto:[log in to unmask]]
>>> On Behalf Of Howard, W A 9 Y B W
>>> Sent: Sunday, September 28, 2014 4:44 AM
>>> To: [log in to unmask]
>>> Subject: Re: US Tower TX-489
>>>
>>> Alan,
>>>
>>> I don't have that specific tower from US Tower, however, I have the
>>> HDX-572.
>>>
>>> Actually my tower was manufactured by Trusteo Tower which was purchased
>>> by
>>> US Tower sometime in the mid to late eighties I believe.
>>>
>>> The HDX-572 is 72 feet fully extended and is four sections instead of
>>> the
>>> five for the TX-489.
>>>
>>> When I purchased the tower in 1978 I couldn't afford the electric winch
>>> and
>>> went with the manual Fulton.
>>>
>>> We have a lot of wind and storms here in central Illinois and if I did
>>> it
>>> again, I would purchase the electric winch. I'm not sure you can buy
>>> this
>>> tower with a manual winch any longer, only the electric.
>>>
>>> As for cranking it up and down, it isn't really that bad. Obviously
>>> coming
>>> down is easier than going up. I haven't really timed it but I can
>>> probably
>>> go full height in under thirty minutes with a few short one or two
>>> minute
>>> breaks.
>>>
>>> If it wasn't such a hassle to get all the antennas down, remove and pour
>>> a
>>> new foundation, I would consider replacing the tower with the motorized
>>> HDX-572. I don't even know if there is a company I could hire to do it
>>> or
>>> not.
>>>
>>> If you have no need to raise or lower more than one or two times a year,
>>> probably not worth it.
>>> 73,
>>>
>>> Howard #3, W A 9 Y B W
>>>
>>> ----- Original Message -----
>>> From: "Alan R. Downing" <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> Sent: Saturday, September 27, 2014 7:32 PM
>>> Subject: US Tower TX-489
>>>
>>>
>>>> Does anyone on the list have a TX-489 tower by US Towers? If so, I'd
>>>> like
>>>> to know if you use a manual winch, or the optional motorized winch. I
>>>> plan
>>>> to put this tower up when the WX turns cooler, but I need to decide now
>>>> whether to buy the motorized winch for it or not. I don't raise and
>>>> lower
>>>> my tower very often, so I am not concerned about how long it takes to
>>>> fully
>>>> lower or raise it, just how much work it takes.
>>>>
>>>>
>>>>
>>>> Thanks for any suggestions.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Alan
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Alan R. Downing
>>>>
>>>> Phoenix, AZ
>>>>
>>>>
>>>
>>>
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