Base Will the U-100 work on the HD73?

[357]

anyone familiar with it?

thanks

 

[Captain Kilowatt]

The U-100 and HD-73 are both Alliance rotators but I think you are asking if the control box from one unit will work with the other rotator unit. The answer I believe is no. IIRC the HD-73 uses a six wire connection while the U-100 uses a five wire connection. Operating voltages are similar however.....20 volts AC.

 

[midnight special]

my u 100 uses 4 wires

 

[nomadradio]

The U100 is a "click-click" control box. A cam inside the rotor rotates once per degree and flips a switch contact to make the control box "click" the indicator on the control box one step while the antenna turns .

The HD73 is more like the CDE rotors with a rheostat (variable resistor) inside the motor unit to feed a moving-needle meter-type direction indicator.

Not even close to compatible.

73

 

[BJ radionut]

http://www.rotorservice.com/prod1 rotor sales.htm

This is the only outlet I know of now that has parts or will service Alliance rotors.The HD73 is a good rotor but the control box is singular to that unit only...twin speed control box.
Scroll down the page you will find them. My understanding when Alliance went out of business many years ago Norm's purchased all the factory parts and now own's the right's to that name.
All the Best
Gary

 

[Captain Kilowatt]

my u 100 uses 4 wires

You are correct but the HD-73 uses six wires so right off the bat it still won't work regardless of any other differences.

 

[357]

I found a CD45 II dated 1984 for $75 from a local ham.
It works perfect and has fresh grease.
Unfortunatly it looks like the bolt pattern is different from the HD73, definitly smaller bolts.

 

[BJ radionut]

CD45 II has about a 15% lighter duty cycle than the HD73...having used a HD73 years ago it is highly underrated IMHO. I had a Huge Mosley Classic 33/ 3 element Tri-bander and a pair of stacked 15 element 2m beams plus a Sigma 5/8th 10m vert on top, for maybe 10-12 yrs on a 54 ft. tower and never had an issue...The tower came down in a Hurricane...rotor was fine!
I would not even try the Mosley on a CD45 II...but just me.
Good Luck
All the Best
Gary

 

[w9cll]

I agree on the difference between the CD45 and the HD73. I used an HD73 for years turning stacked 17b2 and 4 elements for 6 on the tower. I still have the rotor and will put it back in service someday.

 

[357]

ok thanks.
I'd use the hd73 but I didn't have a control box.
The cd45 II was only 75 and it worked perfectly so I grabbed it.
I could always sell it and make money and rebuild the hd73.
I like the side wire mount better and the bolt-on top and it had less "play" in it.

would the cde control work on the hd73?

 

[nomadradio]

The CDE controller uses eight wires and has a solenoid that releases a brake to move the antenna. Two of the wires are used to power the brake solenoid.

The HD73 relies on the extreme gear ratio instead of using a brake, and uses only six wires.

Just too different to adapt one to the other.

73

 

[Captain Kilowatt]

The CDE controller uses eight wires and has a solenoid that releases a brake to move the antenna. Two of the wires are used to power the brake solenoid.

The HD73 relies on the extreme gear ratio instead of using a brake, and uses only six wires.

Just too different to adapt one to the other.

73

Not all the CDE rotators have a brake. Only the larger units like the Ham 4 and Tailtwister do. The CD-44 CD-45 do not have a brake and rely on the gear ratio as well.

 

[357]

I snagged this badboy, sold the CD45 II to pay for it.
https://www.ebay.ca/itm/392008991614?ul_noapp=true

rotortime tried to grab it on me I would have got it for $118